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reserving memory only to enabled features #18

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amery opened this issue May 19, 2012 · 8 comments
Closed

reserving memory only to enabled features #18

amery opened this issue May 19, 2012 · 8 comments

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@amery
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amery commented May 19, 2012

On Fri, 18 May 2012 23:49:26 +0100 David Given sent the following patch to the mailing list:

Attached is a patch which prevents memory being reserved for
framebuffer, G2D and video engine if the relevant bits aren't enabled in
the kernel configuration. This whole area looks very much under
construction, and I've no idea whether this is the right approach or
not, but on my server system this gains me an extra 115MB or so of
usable RAM.

(Incidentally, the G2D area is apparently never reserved. Is that correct?)

http://lists.phcomp.co.uk/pipermail/arm-netbook/attachments/20120518/d327754f/attachment.bin

@amery
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amery commented May 19, 2012

shouldn't this also be bound to the foo_used thing in script.bin?

@amery
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amery commented May 19, 2012

As I'm not yet sure about this I've created yet another branch, wip/allwinner-v3.0-android-v2/memblock_reserve, please comment.

@davidgiven
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Is script.bin still used in v2? I can't find any calls to sw_cfg_get_int() outside arch/mach-sun4i/core.c, and they're both in the #if 0 block.

If the relevant drivers are disabled, then the symbols ve_start, fb_start and g2d_start etc won't be provided, so hopefully anything that tries to use those reserved areas will cause compilation/module load failure. Unless they have hard-coded addresses, of course.

What's the right way to submit an updated path? Check out the branch, modify, push? (I don't know github.)

@amery
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amery commented May 19, 2012

@davidgiven yes, script.bin is still used, and allwinner uses it in newer SoCs too. see arch/arm/mach-sun4i/include/mach/sys_config.h. About submiting you can either make a "fork" here and issue a "pull request" or mail the patches or upload the patches somewhere.

@hno
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hno commented May 19, 2012

Looks ok to me unless there is hardcoded address constants somewhere.

The conditionals on the global variables should be extended into arch/arm/mach-sun4i/include/mach/system.h and drivers cleaned up to use this making compilation fail early.

MALI driver do have hardcoded constants for memory locations and is handled quite uglly with 64MB MALI region completely hidden from Linux memory map instead of reserved, see sw_core_fixup.

memory map:

0x40000000 Memory start
...
0x43000000 64KB SYS_CONFIG
...
0x44000000 48MB(32+16) VE
....
0x58000000 16MB G2D
0x58000000 16MB Memory? (or configurable G2D size)
0x5a000000 32MB Framebuffer
0x5c000000 64MB MALI, Reserved outside Linux memory map
0x60000000 Memory > 512MB

The change to not reserve G2D memory is most likely a bug. Looks like someone tried to clean things up here and did not bother to fix G2D. Maybe G2D is not used in the product these sources are from?

@ghost
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ghost commented May 20, 2012

sw_cfg_get* are used in early boot. script_parser* are used everywhere else. Only the latter handles gpio parameters.
Oh, so that's where the top 64Mb of the first dram module goes! Was wondering.
The G2D unit seems to be a DMA blitter with scaling and colour space conversion; the Disp engine has something similar in its Scaler, although sans DMA?

@davidgiven
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Ah, I see. Okay, I'll update to use #if defined CONFIG_ and check the script. Unfortunately I'm currently fighting unrelated issues so it may be a bit of time until I get round to it. If anyone wants to jump in, go ahead.

And yes, interesting to finally see where that 64MB went!

@davidgiven
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Sorry about the long delay, but I finally have an improved version of this patch. With luck and github willing, it's here:

https://github.com/amery/linux-allwinner/pull/34

This now checks the startup script and only reserves the regions when the particular feature is enabled. If they're not, the relevant symbols get set to 0 which at the worst should cause a clean crash if anything tries to use them rather than random memory corruption. If the feature is not compiled into the kernel at all, the symbols aren't defined.

The video engine (which uses the VE block) doesn't appear to have such a startup script setting.

It also now allocates the G2D block, which upstream wasn't doing --- I think this fixes a bug.

amery pushed a commit that referenced this issue Jun 16, 2012
The warning below triggers on AMD MCM packages because physical package
IDs on the cores of a _physical_ socket are the same. I.e., this field
says which CPUs belong to the same physical package.

However, the same two CPUs belong to two different internal, i.e.
"logical" nodes in the same physical socket which is reflected in the
CPU-to-node map on x86 with NUMA.

Which makes this check wrong on the above topologies so circumvent it.

[    0.444413] Booting Node   0, Processors  #1 #2 #3 #4 #5 Ok.
[    0.461388] ------------[ cut here ]------------
[    0.465997] WARNING: at arch/x86/kernel/smpboot.c:310 topology_sane.clone.1+0x6e/0x81()
[    0.473960] Hardware name: Dinar
[    0.477170] sched: CPU #6's mc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.
[    0.486860] Booting Node   1, Processors  #6
[    0.491104] Modules linked in:
[    0.494141] Pid: 0, comm: swapper/6 Not tainted 3.4.0+ #1
[    0.499510] Call Trace:
[    0.501946]  [<ffffffff8144bf92>] ? topology_sane.clone.1+0x6e/0x81
[    0.508185]  [<ffffffff8102f1fc>] warn_slowpath_common+0x85/0x9d
[    0.514163]  [<ffffffff8102f2b7>] warn_slowpath_fmt+0x46/0x48
[    0.519881]  [<ffffffff8144bf92>] topology_sane.clone.1+0x6e/0x81
[    0.525943]  [<ffffffff8144c234>] set_cpu_sibling_map+0x251/0x371
[    0.532004]  [<ffffffff8144c4ee>] start_secondary+0x19a/0x218
[    0.537729] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.628197]  #7 #8 #9 #10 #11 Ok.
[    0.807108] Booting Node   3, Processors  #12 #13 #14 #15 #16 #17 Ok.
[    0.897587] Booting Node   2, Processors  #18 #19 #20 #21 #22 #23 Ok.
[    0.917443] Brought up 24 CPUs

We ran a topology sanity check test we have here on it and
it all looks ok... hopefully :).

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120529135442.GE29157@aftab.osrc.amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
@amery amery closed this as completed Jul 3, 2012
amery pushed a commit that referenced this issue Sep 8, 2012
…d reasons

commit 5cf02d0 upstream.

We've had some reports of a deadlock where rpciod ends up with a stack
trace like this:

    PID: 2507   TASK: ffff88103691ab40  CPU: 14  COMMAND: "rpciod/14"
     #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9
     #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs]
     #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f
     #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8
     #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs]
     #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs]
     #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670
     #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271
     #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638
     #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f
    #10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e
    #11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f
    #12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad
    #13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942
    #14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a
    #15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9
    #16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b
    #17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808
    #18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c
    #19 [ffff8810343bfce8] inet_create at ffffffff81483ba6
    #20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7
    #21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc]
    #22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc]
    #23 [ffff8810343bfe38] worker_thread at ffffffff810887d0
    #24 [ffff8810343bfee8] kthread at ffffffff8108dd96
    #25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca

rpciod is trying to allocate memory for a new socket to talk to the
server. The VM ends up calling ->releasepage to get more memory, and it
tries to do a blocking commit. That commit can't succeed however without
a connected socket, so we deadlock.

Fix this by setting PF_FSTRANS on the workqueue task prior to doing the
socket allocation, and having nfs_release_page check for that flag when
deciding whether to do a commit call. Also, set PF_FSTRANS
unconditionally in rpc_async_schedule since that function can also do
allocations sometimes.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Oct 6, 2012
…d reasons

commit 5cf02d0 upstream.

We've had some reports of a deadlock where rpciod ends up with a stack
trace like this:

    PID: 2507   TASK: ffff88103691ab40  CPU: 14  COMMAND: "rpciod/14"
     #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9
     #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs]
     #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f
     #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8
     #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs]
     #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs]
     #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670
     #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271
     #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638
     #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f
    #10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e
    #11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f
    #12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad
    #13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942
    #14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a
    #15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9
    #16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b
    #17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808
    #18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c
    #19 [ffff8810343bfce8] inet_create at ffffffff81483ba6
    #20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7
    #21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc]
    #22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc]
    #23 [ffff8810343bfe38] worker_thread at ffffffff810887d0
    #24 [ffff8810343bfee8] kthread at ffffffff8108dd96
    #25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca

rpciod is trying to allocate memory for a new socket to talk to the
server. The VM ends up calling ->releasepage to get more memory, and it
tries to do a blocking commit. That commit can't succeed however without
a connected socket, so we deadlock.

Fix this by setting PF_FSTRANS on the workqueue task prior to doing the
socket allocation, and having nfs_release_page check for that flag when
deciding whether to do a commit call. Also, set PF_FSTRANS
unconditionally in rpc_async_schedule since that function can also do
allocations sometimes.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Oct 13, 2012
…d reasons

We've had some reports of a deadlock where rpciod ends up with a stack
trace like this:

    PID: 2507   TASK: ffff88103691ab40  CPU: 14  COMMAND: "rpciod/14"
     #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9
     #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs]
     #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f
     #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8
     #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs]
     #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs]
     #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670
     #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271
     #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638
     #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f
    #10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e
    #11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f
    #12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad
    #13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942
    #14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a
    #15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9
    #16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b
    #17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808
    #18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c
    #19 [ffff8810343bfce8] inet_create at ffffffff81483ba6
    #20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7
    #21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc]
    #22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc]
    #23 [ffff8810343bfe38] worker_thread at ffffffff810887d0
    #24 [ffff8810343bfee8] kthread at ffffffff8108dd96
    #25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca

rpciod is trying to allocate memory for a new socket to talk to the
server. The VM ends up calling ->releasepage to get more memory, and it
tries to do a blocking commit. That commit can't succeed however without
a connected socket, so we deadlock.

Fix this by setting PF_FSTRANS on the workqueue task prior to doing the
socket allocation, and having nfs_release_page check for that flag when
deciding whether to do a commit call. Also, set PF_FSTRANS
unconditionally in rpc_async_schedule since that function can also do
allocations sometimes.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
amery pushed a commit that referenced this issue Dec 29, 2012
While testing the pid namespace code I hit this nasty warning.

[  176.262617] ------------[ cut here ]------------
[  176.263388] WARNING: at /home/eric/projects/linux/linux-userns-devel/kernel/softirq.c:160 local_bh_enable_ip+0x7a/0xa0()
[  176.265145] Hardware name: Bochs
[  176.265677] Modules linked in:
[  176.266341] Pid: 742, comm: bash Not tainted 3.7.0userns+ #18
[  176.266564] Call Trace:
[  176.266564]  [<ffffffff810a539f>] warn_slowpath_common+0x7f/0xc0
[  176.266564]  [<ffffffff810a53fa>] warn_slowpath_null+0x1a/0x20
[  176.266564]  [<ffffffff810ad9ea>] local_bh_enable_ip+0x7a/0xa0
[  176.266564]  [<ffffffff819308c9>] _raw_spin_unlock_bh+0x19/0x20
[  176.266564]  [<ffffffff8123dbda>] proc_free_inum+0x3a/0x50
[  176.266564]  [<ffffffff8111d0dc>] free_pid_ns+0x1c/0x80
[  176.266564]  [<ffffffff8111d195>] put_pid_ns+0x35/0x50
[  176.266564]  [<ffffffff810c608a>] put_pid+0x4a/0x60
[  176.266564]  [<ffffffff8146b177>] tty_ioctl+0x717/0xc10
[  176.266564]  [<ffffffff810aa4d5>] ? wait_consider_task+0x855/0xb90
[  176.266564]  [<ffffffff81086bf9>] ? default_spin_lock_flags+0x9/0x10
[  176.266564]  [<ffffffff810cab0a>] ? remove_wait_queue+0x5a/0x70
[  176.266564]  [<ffffffff811e37e8>] do_vfs_ioctl+0x98/0x550
[  176.266564]  [<ffffffff810b8a0f>] ? recalc_sigpending+0x1f/0x60
[  176.266564]  [<ffffffff810b9127>] ? __set_task_blocked+0x37/0x80
[  176.266564]  [<ffffffff810ab95b>] ? sys_wait4+0xab/0xf0
[  176.266564]  [<ffffffff811e3d31>] sys_ioctl+0x91/0xb0
[  176.266564]  [<ffffffff810a95f0>] ? task_stopped_code+0x50/0x50
[  176.266564]  [<ffffffff81939199>] system_call_fastpath+0x16/0x1b
[  176.266564] ---[ end trace 387af88219ad6143 ]---

It turns out that spin_unlock_bh(proc_inum_lock) is not safe when
put_pid is called with another spinlock held and irqs disabled.

For now take the easy path and use spin_lock_irqsave(proc_inum_lock)
in proc_free_inum and spin_loc_irq in proc_alloc_inum(proc_inum_lock).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
amery pushed a commit that referenced this issue Mar 3, 2013
Kjell Braden reported this oops:

[  833.211970] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  833.212816] IP: [<          (null)>]           (null)
[  833.213280] PGD 1b9b2067 PUD e9f7067 PMD 0
[  833.213874] Oops: 0010 [#1] SMP
[  833.214344] CPU 0
[  833.214458] Modules linked in: des_generic md4 nls_utf8 cifs vboxvideo drm snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq bnep rfcomm snd_timer bluetooth snd_seq_device ppdev snd vboxguest parport_pc joydev mac_hid soundcore snd_page_alloc psmouse i2c_piix4 serio_raw lp parport usbhid hid e1000
[  833.215629]
[  833.215629] Pid: 1752, comm: mount.cifs Not tainted 3.0.0-rc7-bisectcifs-fec11dd9a0+ #18 innotek GmbH VirtualBox/VirtualBox
[  833.215629] RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
[  833.215629] RSP: 0018:ffff8800119c9c50  EFLAGS: 00010282
[  833.215629] RAX: ffffffffa02186c0 RBX: ffff88000c427780 RCX: 0000000000000000
[  833.215629] RDX: 0000000000000000 RSI: ffff88000c427780 RDI: ffff88000c4362e8
[  833.215629] RBP: ffff8800119c9c88 R08: ffff88001fc15e30 R09: 00000000d69515c7
[  833.215629] R10: ffffffffa0201972 R11: ffff88000e8f6a28 R12: ffff88000c4362e8
[  833.215629] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88001181aaa6
[  833.215629] FS:  00007f2986171700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  833.215629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  833.215629] CR2: 0000000000000000 CR3: 000000001b982000 CR4: 00000000000006f0
[  833.215629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  833.215629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  833.215629] Process mount.cifs (pid: 1752, threadinfo ffff8800119c8000, task ffff88001c1c16f0)
[  833.215629] Stack:
[  833.215629]  ffffffff8116a9b5 ffff8800119c9c88 ffffffff81178075 0000000000000286
[  833.215629]  0000000000000000 ffff88000c4276c0 ffff8800119c9ce8 ffff8800119c9cc8
[  833.215629]  ffffffff8116b06e ffff88001bc6fc00 ffff88000c4276c0 ffff88000c4276c0
[  833.215629] Call Trace:
[  833.215629]  [<ffffffff8116a9b5>] ? d_alloc_and_lookup+0x45/0x90
[  833.215629]  [<ffffffff81178075>] ? d_lookup+0x35/0x60
[  833.215629]  [<ffffffff8116b06e>] __lookup_hash.part.14+0x9e/0xc0
[  833.215629]  [<ffffffff8116b1d6>] lookup_one_len+0x146/0x1e0
[  833.215629]  [<ffffffff815e4f7e>] ? _raw_spin_lock+0xe/0x20
[  833.215629]  [<ffffffffa01eef0d>] cifs_do_mount+0x26d/0x500 [cifs]
[  833.215629]  [<ffffffff81163bd3>] mount_fs+0x43/0x1b0
[  833.215629]  [<ffffffff8117d41a>] vfs_kern_mount+0x6a/0xd0
[  833.215629]  [<ffffffff8117e584>] do_kern_mount+0x54/0x110
[  833.215629]  [<ffffffff8117fdc2>] do_mount+0x262/0x840
[  833.215629]  [<ffffffff81108a0e>] ? __get_free_pages+0xe/0x50
[  833.215629]  [<ffffffff8117f9ca>] ? copy_mount_options+0x3a/0x180
[  833.215629]  [<ffffffff8118075d>] sys_mount+0x8d/0xe0
[  833.215629]  [<ffffffff815ece82>] system_call_fastpath+0x16/0x1b
[  833.215629] Code:  Bad RIP value.
[  833.215629] RIP  [<          (null)>]           (null)
[  833.215629]  RSP <ffff8800119c9c50>
[  833.215629] CR2: 0000000000000000
[  833.238525] ---[ end trace ec00758b8d44f529 ]---

When walking down the path on the server, it's possible to hit a
symlink. The path walking code assumes that the caller will handle that
situation properly, but cifs_get_root() isn't set up for it. This patch
prevents the oops by simply returning an error.

A better solution would be to try and chase the symlinks here, but that's
fairly complicated to handle.

Fixes:

    https://bugzilla.kernel.org/show_bug.cgi?id=53221

Reported-and-tested-by: Kjell Braden <afflux@pentabarf.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
amery pushed a commit that referenced this issue Apr 10, 2013
commit ce2ac52 upstream.

Kjell Braden reported this oops:

[  833.211970] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  833.212816] IP: [<          (null)>]           (null)
[  833.213280] PGD 1b9b2067 PUD e9f7067 PMD 0
[  833.213874] Oops: 0010 [#1] SMP
[  833.214344] CPU 0
[  833.214458] Modules linked in: des_generic md4 nls_utf8 cifs vboxvideo drm snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq bnep rfcomm snd_timer bluetooth snd_seq_device ppdev snd vboxguest parport_pc joydev mac_hid soundcore snd_page_alloc psmouse i2c_piix4 serio_raw lp parport usbhid hid e1000
[  833.215629]
[  833.215629] Pid: 1752, comm: mount.cifs Not tainted 3.0.0-rc7-bisectcifs-fec11dd9a0+ #18 innotek GmbH VirtualBox/VirtualBox
[  833.215629] RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
[  833.215629] RSP: 0018:ffff8800119c9c50  EFLAGS: 00010282
[  833.215629] RAX: ffffffffa02186c0 RBX: ffff88000c427780 RCX: 0000000000000000
[  833.215629] RDX: 0000000000000000 RSI: ffff88000c427780 RDI: ffff88000c4362e8
[  833.215629] RBP: ffff8800119c9c88 R08: ffff88001fc15e30 R09: 00000000d69515c7
[  833.215629] R10: ffffffffa0201972 R11: ffff88000e8f6a28 R12: ffff88000c4362e8
[  833.215629] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88001181aaa6
[  833.215629] FS:  00007f2986171700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  833.215629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  833.215629] CR2: 0000000000000000 CR3: 000000001b982000 CR4: 00000000000006f0
[  833.215629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  833.215629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  833.215629] Process mount.cifs (pid: 1752, threadinfo ffff8800119c8000, task ffff88001c1c16f0)
[  833.215629] Stack:
[  833.215629]  ffffffff8116a9b5 ffff8800119c9c88 ffffffff81178075 0000000000000286
[  833.215629]  0000000000000000 ffff88000c4276c0 ffff8800119c9ce8 ffff8800119c9cc8
[  833.215629]  ffffffff8116b06e ffff88001bc6fc00 ffff88000c4276c0 ffff88000c4276c0
[  833.215629] Call Trace:
[  833.215629]  [<ffffffff8116a9b5>] ? d_alloc_and_lookup+0x45/0x90
[  833.215629]  [<ffffffff81178075>] ? d_lookup+0x35/0x60
[  833.215629]  [<ffffffff8116b06e>] __lookup_hash.part.14+0x9e/0xc0
[  833.215629]  [<ffffffff8116b1d6>] lookup_one_len+0x146/0x1e0
[  833.215629]  [<ffffffff815e4f7e>] ? _raw_spin_lock+0xe/0x20
[  833.215629]  [<ffffffffa01eef0d>] cifs_do_mount+0x26d/0x500 [cifs]
[  833.215629]  [<ffffffff81163bd3>] mount_fs+0x43/0x1b0
[  833.215629]  [<ffffffff8117d41a>] vfs_kern_mount+0x6a/0xd0
[  833.215629]  [<ffffffff8117e584>] do_kern_mount+0x54/0x110
[  833.215629]  [<ffffffff8117fdc2>] do_mount+0x262/0x840
[  833.215629]  [<ffffffff81108a0e>] ? __get_free_pages+0xe/0x50
[  833.215629]  [<ffffffff8117f9ca>] ? copy_mount_options+0x3a/0x180
[  833.215629]  [<ffffffff8118075d>] sys_mount+0x8d/0xe0
[  833.215629]  [<ffffffff815ece82>] system_call_fastpath+0x16/0x1b
[  833.215629] Code:  Bad RIP value.
[  833.215629] RIP  [<          (null)>]           (null)
[  833.215629]  RSP <ffff8800119c9c50>
[  833.215629] CR2: 0000000000000000
[  833.238525] ---[ end trace ec00758b8d44f529 ]---

When walking down the path on the server, it's possible to hit a
symlink. The path walking code assumes that the caller will handle that
situation properly, but cifs_get_root() isn't set up for it. This patch
prevents the oops by simply returning an error.

A better solution would be to try and chase the symlinks here, but that's
fairly complicated to handle.

Fixes:

    https://bugzilla.kernel.org/show_bug.cgi?id=53221

Reported-and-tested-by: Kjell Braden <afflux@pentabarf.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Apr 10, 2013
commit ce2ac52 upstream.

Kjell Braden reported this oops:

[  833.211970] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  833.212816] IP: [<          (null)>]           (null)
[  833.213280] PGD 1b9b2067 PUD e9f7067 PMD 0
[  833.213874] Oops: 0010 [#1] SMP
[  833.214344] CPU 0
[  833.214458] Modules linked in: des_generic md4 nls_utf8 cifs vboxvideo drm snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq bnep rfcomm snd_timer bluetooth snd_seq_device ppdev snd vboxguest parport_pc joydev mac_hid soundcore snd_page_alloc psmouse i2c_piix4 serio_raw lp parport usbhid hid e1000
[  833.215629]
[  833.215629] Pid: 1752, comm: mount.cifs Not tainted 3.0.0-rc7-bisectcifs-fec11dd9a0+ #18 innotek GmbH VirtualBox/VirtualBox
[  833.215629] RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
[  833.215629] RSP: 0018:ffff8800119c9c50  EFLAGS: 00010282
[  833.215629] RAX: ffffffffa02186c0 RBX: ffff88000c427780 RCX: 0000000000000000
[  833.215629] RDX: 0000000000000000 RSI: ffff88000c427780 RDI: ffff88000c4362e8
[  833.215629] RBP: ffff8800119c9c88 R08: ffff88001fc15e30 R09: 00000000d69515c7
[  833.215629] R10: ffffffffa0201972 R11: ffff88000e8f6a28 R12: ffff88000c4362e8
[  833.215629] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88001181aaa6
[  833.215629] FS:  00007f2986171700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  833.215629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  833.215629] CR2: 0000000000000000 CR3: 000000001b982000 CR4: 00000000000006f0
[  833.215629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  833.215629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  833.215629] Process mount.cifs (pid: 1752, threadinfo ffff8800119c8000, task ffff88001c1c16f0)
[  833.215629] Stack:
[  833.215629]  ffffffff8116a9b5 ffff8800119c9c88 ffffffff81178075 0000000000000286
[  833.215629]  0000000000000000 ffff88000c4276c0 ffff8800119c9ce8 ffff8800119c9cc8
[  833.215629]  ffffffff8116b06e ffff88001bc6fc00 ffff88000c4276c0 ffff88000c4276c0
[  833.215629] Call Trace:
[  833.215629]  [<ffffffff8116a9b5>] ? d_alloc_and_lookup+0x45/0x90
[  833.215629]  [<ffffffff81178075>] ? d_lookup+0x35/0x60
[  833.215629]  [<ffffffff8116b06e>] __lookup_hash.part.14+0x9e/0xc0
[  833.215629]  [<ffffffff8116b1d6>] lookup_one_len+0x146/0x1e0
[  833.215629]  [<ffffffff815e4f7e>] ? _raw_spin_lock+0xe/0x20
[  833.215629]  [<ffffffffa01eef0d>] cifs_do_mount+0x26d/0x500 [cifs]
[  833.215629]  [<ffffffff81163bd3>] mount_fs+0x43/0x1b0
[  833.215629]  [<ffffffff8117d41a>] vfs_kern_mount+0x6a/0xd0
[  833.215629]  [<ffffffff8117e584>] do_kern_mount+0x54/0x110
[  833.215629]  [<ffffffff8117fdc2>] do_mount+0x262/0x840
[  833.215629]  [<ffffffff81108a0e>] ? __get_free_pages+0xe/0x50
[  833.215629]  [<ffffffff8117f9ca>] ? copy_mount_options+0x3a/0x180
[  833.215629]  [<ffffffff8118075d>] sys_mount+0x8d/0xe0
[  833.215629]  [<ffffffff815ece82>] system_call_fastpath+0x16/0x1b
[  833.215629] Code:  Bad RIP value.
[  833.215629] RIP  [<          (null)>]           (null)
[  833.215629]  RSP <ffff8800119c9c50>
[  833.215629] CR2: 0000000000000000
[  833.238525] ---[ end trace ec00758b8d44f529 ]---

When walking down the path on the server, it's possible to hit a
symlink. The path walking code assumes that the caller will handle that
situation properly, but cifs_get_root() isn't set up for it. This patch
prevents the oops by simply returning an error.

A better solution would be to try and chase the symlinks here, but that's
fairly complicated to handle.

Fixes:

    https://bugzilla.kernel.org/show_bug.cgi?id=53221

Reported-and-tested-by: Kjell Braden <afflux@pentabarf.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Jul 11, 2013
Several people reported the warning: "kernel BUG at kernel/timer.c:729!"
and the stack trace is:

	#7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905
	#8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at ffffffffa0731d25 [bridge]
	#9 [ffff880214d25c80] br_multicast_disable_port+88 at ffffffffa0732948 [bridge]
	#10 [ffff880214d25cb0] br_stp_disable_port+154 at ffffffffa072bcca [bridge]
	#11 [ffff880214d25ce8] br_device_event+520 at ffffffffa072a4e8 [bridge]
	#12 [ffff880214d25d18] notifier_call_chain+76 at ffffffff8164aafc
	#13 [ffff880214d25d50] raw_notifier_call_chain+22 at ffffffff810858f6
	#14 [ffff880214d25d60] call_netdevice_notifiers+45 at ffffffff81536aad
	#15 [ffff880214d25d80] dev_close_many+183 at ffffffff81536d17
	#16 [ffff880214d25dc0] rollback_registered_many+168 at ffffffff81537f68
	#17 [ffff880214d25de8] rollback_registered+49 at ffffffff81538101
	#18 [ffff880214d25e10] unregister_netdevice_queue+72 at ffffffff815390d8
	#19 [ffff880214d25e30] __tun_detach+272 at ffffffffa074c2f0 [tun]
	#20 [ffff880214d25e88] tun_chr_close+45 at ffffffffa074c4bd [tun]
	#21 [ffff880214d25ea8] __fput+225 at ffffffff8119b1f1
	#22 [ffff880214d25ef0] ____fput+14 at ffffffff8119b3fe
	#23 [ffff880214d25f00] task_work_run+159 at ffffffff8107cf7f
	#24 [ffff880214d25f30] do_notify_resume+97 at ffffffff810139e1
	#25 [ffff880214d25f50] int_signal+18 at ffffffff8164f292

this is due to I forgot to check if mp->timer is armed in
br_multicast_del_pg(). This bug is introduced by
commit 9f00b2e (bridge: only expire the mdb entry
when query is received).

Same for __br_mdb_del().

Tested-by: poma <pomidorabelisima@gmail.com>
Reported-by: LiYonghua <809674045@qq.com>
Reported-by: Robert Hancock <hancockrwd@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
turl pushed a commit that referenced this issue Aug 5, 2013
…s struct file

The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Cc: stable@vger.kernel.org
Signed-off-by: Harshula Jayasuriya <harshula@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
amery pushed a commit that referenced this issue Aug 14, 2013
current_cpu_type() is not preemption-safe.
If CONFIG_PREEMPT is enabled then mipsxx_reg_setup() can be called from preemptible state.
Added get_cpu()/put_cpu() pair to make it preemption-safe.

This was found while testing oprofile with CONFIG_DEBUG_PREEMPT enable.

/usr/zntestsuite # opcontrol --init
/usr/zntestsuite # opcontrol --setup --event=L2_CACHE_ACCESSES:500 --event=L2_CACHE_MISSES:500 --no-vmlinux
/usr/zntestsuite # opcontrol --start
Using 2.6+ OProfile kernel interface.
BUG: using smp_processor_id() in preemptible [00000000] code: oprofiled/1362
caller is mipsxx_reg_setup+0x11c/0x164
CPU: 0 PID: 1362 Comm: oprofiled Not tainted 3.10.4 #18
Stack : 00000006 70757465 00000000 00000000 00000000 00000000 80b173f6 00000037
          80b10000 00000000 80b21614 88f5a220 00000000 00000000 00000000 00000000
          00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
          00000000 00000000 00000000 89c49c00 89c49c2c 80721254 807b7927 8012c1d0
          80b10000 80721254 00000000 00000552 88f5a220 80b1335c 807b78e6 89c49ba8
          ...
Call Trace:
[<801099a4>] show_stack+0x64/0x7c
[<80665520>] dump_stack+0x20/0x2c
[<803a2250>] debug_smp_processor_id+0xe0/0xf0
[<8052df24>] mipsxx_reg_setup+0x11c/0x164
[<8052cd70>] op_mips_setup+0x24/0x4c
[<80529cfc>] oprofile_setup+0x5c/0x12c
[<8052b9f8>] event_buffer_open+0x78/0xf8
[<801c3150>] do_dentry_open.isra.15+0x2b8/0x3b0
[<801c3270>] finish_open+0x28/0x4c
[<801d49b8>] do_last.isra.41+0x2cc/0xd00
[<801d54a0>] path_openat+0xb4/0x4c4
[<801d5c44>] do_filp_open+0x3c/0xac
[<801c4744>] do_sys_open+0x110/0x1f4
[<8010f47c>] stack_done+0x20/0x44

Bug reported and original patch by Jerin Jacob <jerinjacobk@gmail.com>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Jerin Jacob <jerinjacobk@gmail.com>
amery pushed a commit that referenced this issue Sep 20, 2013
When booting secondary CPUs, announce_cpu() is called to show which cpu has
been brought up. For example:

[    0.402751] smpboot: Booting Node   0, Processors  #1 #2 #3 #4 #5 OK
[    0.525667] smpboot: Booting Node   1, Processors  #6 #7 #8 #9 #10 #11 OK
[    0.755592] smpboot: Booting Node   0, Processors  #12 #13 #14 #15 #16 #17 OK
[    0.890495] smpboot: Booting Node   1, Processors  #18 #19 #20 #21 #22 #23

But the last "OK" is lost, because 'nr_cpu_ids-1' represents the maximum
possible cpu id. It should use the maximum present cpu id in case not all
CPUs booted up.

Signed-off-by: Libin <huawei.libin@huawei.com>
Cc: <guohanjun@huawei.com>
Cc: <wangyijing@huawei.com>
Cc: <fenghua.yu@intel.com>
Cc: <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1378378676-18276-1-git-send-email-huawei.libin@huawei.com
[ tweaked the changelog, removed unnecessary line break, tweaked the format to align the fields vertically. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
amery pushed a commit that referenced this issue Sep 21, 2013
…s struct file

commit e4daf1f upstream.

The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Signed-off-by: Harshula Jayasuriya <harshula@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Nov 1, 2013
When memcg code needs to know whether any given memcg has children, it
uses the cgroup child iteration primitives and returns true/false
depending on whether the iteration loop is executed at least once or
not.

Because a cgroup's list of children is RCU protected, these primitives
require the RCU read-lock to be held, which is not the case for all
memcg callers.  This results in the following splat when e.g.  enabling
hierarchy mode:

  WARNING: CPU: 3 PID: 1 at kernel/cgroup.c:3043 css_next_child+0xa3/0x160()
  CPU: 3 PID: 1 Comm: systemd Not tainted 3.12.0-rc5-00117-g83f11a9-dirty #18
  Hardware name: LENOVO 3680B56/3680B56, BIOS 6QET69WW (1.39 ) 04/26/2012
  Call Trace:
    dump_stack+0x54/0x74
    warn_slowpath_common+0x78/0xa0
    warn_slowpath_null+0x1a/0x20
    css_next_child+0xa3/0x160
    mem_cgroup_hierarchy_write+0x5b/0xa0
    cgroup_file_write+0x108/0x2a0
    vfs_write+0xbd/0x1e0
    SyS_write+0x4c/0xa0
    system_call_fastpath+0x16/0x1b

In the memcg case, we only care about children when we are attempting to
modify inheritable attributes interactively.  Racing with deletion could
mean a spurious -EBUSY, no problem.  Racing with addition is handled
just fine as well through the memcg_create_mutex: if the child group is
not on the list after the mutex is acquired, it won't be initialized
from the parent's attributes until after the unlock.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
amery pushed a commit that referenced this issue Nov 12, 2013
As the new x86 CPU bootup printout format code maintainer, I am
taking immediate action to improve and clean (and thus indulge
my OCD) the reporting of the cores when coming up online.

Fix padding to a right-hand alignment, cleanup code and bind
reporting width to the max number of supported CPUs on the
system, like this:

 [    0.074509] smpboot: Booting Node   0, Processors:      #1  #2  #3  #4  #5  #6  #7 OK
 [    0.644008] smpboot: Booting Node   1, Processors:  #8  #9 #10 #11 #12 #13 #14 #15 OK
 [    1.245006] smpboot: Booting Node   2, Processors: #16 #17 #18 #19 #20 #21 #22 #23 OK
 [    1.864005] smpboot: Booting Node   3, Processors: #24 #25 #26 #27 #28 #29 #30 #31 OK
 [    2.489005] smpboot: Booting Node   4, Processors: #32 #33 #34 #35 #36 #37 #38 #39 OK
 [    3.093005] smpboot: Booting Node   5, Processors: #40 #41 #42 #43 #44 #45 #46 #47 OK
 [    3.698005] smpboot: Booting Node   6, Processors: #48 #49 #50 #51 #52 #53 #54 #55 OK
 [    4.304005] smpboot: Booting Node   7, Processors: #56 #57 #58 #59 #60 #61 #62 #63 OK
 [    4.961413] Brought up 64 CPUs

and this:

 [    0.072367] smpboot: Booting Node   0, Processors:    #1 #2 #3 #4 #5 #6 #7 OK
 [    0.686329] Brought up 8 CPUs

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Libin <huawei.libin@huawei.com>
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/20130927143554.GF4422@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
amery pushed a commit that referenced this issue Nov 12, 2013
Turn it into (for example):

[    0.073380] x86: Booting SMP configuration:
[    0.074005] .... node   #0, CPUs:          #1   #2   #3   #4   #5   #6   #7
[    0.603005] .... node   #1, CPUs:     #8   #9  #10  #11  #12  #13  #14  #15
[    1.200005] .... node   #2, CPUs:    #16  #17  #18  #19  #20  #21  #22  #23
[    1.796005] .... node   #3, CPUs:    #24  #25  #26  #27  #28  #29  #30  #31
[    2.393005] .... node   #4, CPUs:    #32  #33  #34  #35  #36  #37  #38  #39
[    2.996005] .... node   #5, CPUs:    #40  #41  #42  #43  #44  #45  #46  #47
[    3.600005] .... node   #6, CPUs:    #48  #49  #50  #51  #52  #53  #54  #55
[    4.202005] .... node   #7, CPUs:    #56  #57  #58  #59  #60  #61  #62  #63
[    4.811005] .... node   #8, CPUs:    #64  #65  #66  #67  #68  #69  #70  #71
[    5.421006] .... node   #9, CPUs:    #72  #73  #74  #75  #76  #77  #78  #79
[    6.032005] .... node  #10, CPUs:    #80  #81  #82  #83  #84  #85  #86  #87
[    6.648006] .... node  #11, CPUs:    #88  #89  #90  #91  #92  #93  #94  #95
[    7.262005] .... node  #12, CPUs:    #96  #97  #98  #99 #100 #101 #102 #103
[    7.865005] .... node  #13, CPUs:   #104 #105 #106 #107 #108 #109 #110 #111
[    8.466005] .... node  #14, CPUs:   #112 #113 #114 #115 #116 #117 #118 #119
[    9.073006] .... node  #15, CPUs:   #120 #121 #122 #123 #124 #125 #126 #127
[    9.679901] x86: Booted up 16 nodes, 128 CPUs

and drop useless elements.

Change num_digits() to hpa's division-avoiding, cell-phone-typed
version which he went at great lengths and pains to submit on a
Saturday evening.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: huawei.libin@huawei.com
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130930095624.GB16383@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
amery pushed a commit that referenced this issue Nov 14, 2013
The probe function is supposed to return NULL on failure (as we can see in
kobj_lookup: kobj = probe(dev, index, data); ... if (kobj) return kobj;

However, in loop and brd, it returns negative error from ERR_PTR.

This causes a crash if we simulate disk allocation failure and run
less -f /dev/loop0 because the negative number is interpreted as a pointer:

BUG: unable to handle kernel NULL pointer dereference at 00000000000002b4
IP: [<ffffffff8118b188>] __blkdev_get+0x28/0x450
PGD 23c677067 PUD 23d6d1067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: loop hpfs nvidia(PO) ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_stats cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_conservative hid_generic spadfs usbhid hid fuse raid0 snd_usb_audio snd_pcm_oss snd_mixer_oss md_mod snd_pcm snd_timer snd_page_alloc snd_hwdep snd_usbmidi_lib dmi_sysfs snd_rawmidi nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd soundcore lm85 hwmon_vid ohci_hcd ehci_pci ehci_hcd serverworks sata_svw libata acpi_cpufreq freq_table mperf ide_core usbcore kvm_amd kvm tg3 i2c_piix4 libphy microcode e100 usb_common ptp skge i2c_core pcspkr k10temp evdev floppy hwmon pps_core mii rtc_cmos button processor unix [last unloaded: nvidia]
CPU: 1 PID: 6831 Comm: less Tainted: P        W  O 3.10.15-devel #18
Hardware name: empty empty/S3992-E, BIOS 'V1.06   ' 06/09/2009
task: ffff880203cc6bc0 ti: ffff88023e47c000 task.ti: ffff88023e47c000
RIP: 0010:[<ffffffff8118b188>]  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
RSP: 0018:ffff88023e47dbd8  EFLAGS: 00010286
RAX: ffffffffffffff74 RBX: ffffffffffffff74 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff88023e47dc18 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88023f519658
R13: ffffffff8118c300 R14: 0000000000000000 R15: ffff88023f519640
FS:  00007f2070bf7700(0000) GS:ffff880247400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002b4 CR3: 000000023da1d000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 0000000000000002 0000001d00000000 000000003e47dc50 ffff88023f519640
 ffff88043d5bb668 ffffffff8118c300 ffff88023d683550 ffff88023e47de60
 ffff88023e47dc98 ffffffff8118c10d 0000001d81605698 0000000000000292
Call Trace:
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c10d>] blkdev_get+0x1dd/0x370
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c365>] blkdev_open+0x65/0x80
 [<ffffffff8114d12e>] do_dentry_open.isra.18+0x23e/0x2f0
 [<ffffffff8114d214>] finish_open+0x34/0x50
 [<ffffffff8115e122>] do_last.isra.62+0x2d2/0xc50
 [<ffffffff8115eb58>] path_openat.isra.63+0xb8/0x4d0
 [<ffffffff81115a8e>] ? might_fault+0x4e/0xa0
 [<ffffffff8115f4f0>] do_filp_open+0x40/0x90
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8116db85>] ? __alloc_fd+0xa5/0x1f0
 [<ffffffff8114e45f>] do_sys_open+0xef/0x1d0
 [<ffffffff8114e559>] SyS_open+0x19/0x20
 [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f
Code: 44 00 00 55 48 89 e5 41 57 49 89 ff 41 56 41 89 d6 41 55 41 54 4c 8d 67 18 53 48 83 ec 18 89 75 cc e9 f2 00 00 00 0f 1f 44 00 00 <48> 8b 80 40 03 00 00 48 89 df 4c 8b 68 58 e8 d5
a4 07 00 44 89
RIP  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
 RSP <ffff88023e47dbd8>
CR2: 00000000000002b4
---[ end trace bb7f32dbf02398dc ]---

The brd change should be backported to stable kernels starting with 2.6.25.
The loop change should be backported to stable kernels starting with 2.6.22.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org	# 2.6.22+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
amery pushed a commit that referenced this issue Dec 2, 2013
…culation

Currently mx53 (CortexA8) running at 1GHz reports:
Calibrating delay loop... 663.55 BogoMIPS (lpj=3317760)

Tom Evans verified that alignments of 0x0 and 0x8 run the two instructions of __loop_delay in one clock cycle (1 clock/loop), while alignments of 0x4 and 0xc take 3 clocks to run the loop twice. (1.5 clock/loop)

The original object code looks like this:

00000010 <__loop_const_udelay>:
  10:	e3e01000 	mvn	r1, #0
  14:	e51f201c 	ldr	r2, [pc, #-28]	; 0 <__loop_udelay-0x8>
  18:	e5922000 	ldr	r2, [r2]
  1c:	e0800921 	add	r0, r0, r1, lsr #18
  20:	e1a00720 	lsr	r0, r0, #14
  24:	e0822b21 	add	r2, r2, r1, lsr #22
  28:	e1a02522 	lsr	r2, r2, #10
  2c:	e0000092 	mul	r0, r2, r0
  30:	e0800d21 	add	r0, r0, r1, lsr #26
  34:	e1b00320 	lsrs	r0, r0, #6
  38:	01a0f00e 	moveq	pc, lr

0000003c <__loop_delay>:
  3c:	e2500001 	subs	r0, r0, #1
  40:	8afffffe 	bhi	3c <__loop_delay>
  44:	e1a0f00e 	mov	pc, lr

After adding the 'align 3' directive to __loop_delay (align to 8 bytes):

00000010 <__loop_const_udelay>:
  10:	e3e01000 	mvn	r1, #0
  14:	e51f201c 	ldr	r2, [pc, #-28]	; 0 <__loop_udelay-0x8>
  18:	e5922000 	ldr	r2, [r2]
  1c:	e0800921 	add	r0, r0, r1, lsr #18
  20:	e1a00720 	lsr	r0, r0, #14
  24:	e0822b21 	add	r2, r2, r1, lsr #22
  28:	e1a02522 	lsr	r2, r2, #10
  2c:	e0000092 	mul	r0, r2, r0
  30:	e0800d21 	add	r0, r0, r1, lsr #26
  34:	e1b00320 	lsrs	r0, r0, #6
  38:	01a0f00e 	moveq	pc, lr
  3c:	e320f000 	nop	{0}

00000040 <__loop_delay>:
  40:	e2500001 	subs	r0, r0, #1
  44:	8afffffe 	bhi	40 <__loop_delay>
  48:	e1a0f00e 	mov	pc, lr
  4c:	e320f000 	nop	{0}

, which now reports:
Calibrating delay loop... 996.14 BogoMIPS (lpj=4980736)

Some more test results:

On mx31 (ARM1136) running at 532 MHz, before the patch:
Calibrating delay loop... 351.43 BogoMIPS (lpj=1757184)

On mx31 (ARM1136) running at 532 MHz after the patch:
Calibrating delay loop... 528.79 BogoMIPS (lpj=2643968)

Also tested on mx6 (CortexA9) and on mx27 (ARM926), which shows the same
BogoMIPS value before and after this patch.

Reported-by: Tom Evans <tom_usenet@optusnet.com.au>
Suggested-by: Tom Evans <tom_usenet@optusnet.com.au>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
chenbd pushed a commit to chenbd/linux-sunxi that referenced this issue Dec 18, 2013
commit a207f59 upstream.

The probe function is supposed to return NULL on failure (as we can see in
kobj_lookup: kobj = probe(dev, index, data); ... if (kobj) return kobj;

However, in loop and brd, it returns negative error from ERR_PTR.

This causes a crash if we simulate disk allocation failure and run
less -f /dev/loop0 because the negative number is interpreted as a pointer:

BUG: unable to handle kernel NULL pointer dereference at 00000000000002b4
IP: [<ffffffff8118b188>] __blkdev_get+0x28/0x450
PGD 23c677067 PUD 23d6d1067 PMD 0
Oops: 0000 [linux-sunxi#1] PREEMPT SMP
Modules linked in: loop hpfs nvidia(PO) ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_stats cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_conservative hid_generic spadfs usbhid hid fuse raid0 snd_usb_audio snd_pcm_oss snd_mixer_oss md_mod snd_pcm snd_timer snd_page_alloc snd_hwdep snd_usbmidi_lib dmi_sysfs snd_rawmidi nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd soundcore lm85 hwmon_vid ohci_hcd ehci_pci ehci_hcd serverworks sata_svw libata acpi_cpufreq freq_table mperf ide_core usbcore kvm_amd kvm tg3 i2c_piix4 libphy microcode e100 usb_common ptp skge i2c_core pcspkr k10temp evdev floppy hwmon pps_core mii rtc_cmos button processor unix [last unloaded: nvidia]
CPU: 1 PID: 6831 Comm: less Tainted: P        W  O 3.10.15-devel linux-sunxi#18
Hardware name: empty empty/S3992-E, BIOS 'V1.06   ' 06/09/2009
task: ffff880203cc6bc0 ti: ffff88023e47c000 task.ti: ffff88023e47c000
RIP: 0010:[<ffffffff8118b188>]  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
RSP: 0018:ffff88023e47dbd8  EFLAGS: 00010286
RAX: ffffffffffffff74 RBX: ffffffffffffff74 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff88023e47dc18 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88023f519658
R13: ffffffff8118c300 R14: 0000000000000000 R15: ffff88023f519640
FS:  00007f2070bf7700(0000) GS:ffff880247400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002b4 CR3: 000000023da1d000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 0000000000000002 0000001d00000000 000000003e47dc50 ffff88023f519640
 ffff88043d5bb668 ffffffff8118c300 ffff88023d683550 ffff88023e47de60
 ffff88023e47dc98 ffffffff8118c10d 0000001d81605698 0000000000000292
Call Trace:
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c10d>] blkdev_get+0x1dd/0x370
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c365>] blkdev_open+0x65/0x80
 [<ffffffff8114d12e>] do_dentry_open.isra.18+0x23e/0x2f0
 [<ffffffff8114d214>] finish_open+0x34/0x50
 [<ffffffff8115e122>] do_last.isra.62+0x2d2/0xc50
 [<ffffffff8115eb58>] path_openat.isra.63+0xb8/0x4d0
 [<ffffffff81115a8e>] ? might_fault+0x4e/0xa0
 [<ffffffff8115f4f0>] do_filp_open+0x40/0x90
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8116db85>] ? __alloc_fd+0xa5/0x1f0
 [<ffffffff8114e45f>] do_sys_open+0xef/0x1d0
 [<ffffffff8114e559>] SyS_open+0x19/0x20
 [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f
Code: 44 00 00 55 48 89 e5 41 57 49 89 ff 41 56 41 89 d6 41 55 41 54 4c 8d 67 18 53 48 83 ec 18 89 75 cc e9 f2 00 00 00 0f 1f 44 00 00 <48> 8b 80 40 03 00 00 48 89 df 4c 8b 68 58 e8 d5
a4 07 00 44 89
RIP  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
 RSP <ffff88023e47dbd8>
CR2: 00000000000002b4
---[ end trace bb7f32dbf02398dc ]---

The brd change should be backported to stable kernels starting with 2.6.25.
The loop change should be backported to stable kernels starting with 2.6.22.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Dec 30, 2013
commit a207f59 upstream.

The probe function is supposed to return NULL on failure (as we can see in
kobj_lookup: kobj = probe(dev, index, data); ... if (kobj) return kobj;

However, in loop and brd, it returns negative error from ERR_PTR.

This causes a crash if we simulate disk allocation failure and run
less -f /dev/loop0 because the negative number is interpreted as a pointer:

BUG: unable to handle kernel NULL pointer dereference at 00000000000002b4
IP: [<ffffffff8118b188>] __blkdev_get+0x28/0x450
PGD 23c677067 PUD 23d6d1067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: loop hpfs nvidia(PO) ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_stats cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_conservative hid_generic spadfs usbhid hid fuse raid0 snd_usb_audio snd_pcm_oss snd_mixer_oss md_mod snd_pcm snd_timer snd_page_alloc snd_hwdep snd_usbmidi_lib dmi_sysfs snd_rawmidi nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd soundcore lm85 hwmon_vid ohci_hcd ehci_pci ehci_hcd serverworks sata_svw libata acpi_cpufreq freq_table mperf ide_core usbcore kvm_amd kvm tg3 i2c_piix4 libphy microcode e100 usb_common ptp skge i2c_core pcspkr k10temp evdev floppy hwmon pps_core mii rtc_cmos button processor unix [last unloaded: nvidia]
CPU: 1 PID: 6831 Comm: less Tainted: P        W  O 3.10.15-devel #18
Hardware name: empty empty/S3992-E, BIOS 'V1.06   ' 06/09/2009
task: ffff880203cc6bc0 ti: ffff88023e47c000 task.ti: ffff88023e47c000
RIP: 0010:[<ffffffff8118b188>]  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
RSP: 0018:ffff88023e47dbd8  EFLAGS: 00010286
RAX: ffffffffffffff74 RBX: ffffffffffffff74 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff88023e47dc18 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88023f519658
R13: ffffffff8118c300 R14: 0000000000000000 R15: ffff88023f519640
FS:  00007f2070bf7700(0000) GS:ffff880247400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002b4 CR3: 000000023da1d000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 0000000000000002 0000001d00000000 000000003e47dc50 ffff88023f519640
 ffff88043d5bb668 ffffffff8118c300 ffff88023d683550 ffff88023e47de60
 ffff88023e47dc98 ffffffff8118c10d 0000001d81605698 0000000000000292
Call Trace:
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c10d>] blkdev_get+0x1dd/0x370
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60
 [<ffffffff8118c365>] blkdev_open+0x65/0x80
 [<ffffffff8114d12e>] do_dentry_open.isra.18+0x23e/0x2f0
 [<ffffffff8114d214>] finish_open+0x34/0x50
 [<ffffffff8115e122>] do_last.isra.62+0x2d2/0xc50
 [<ffffffff8115eb58>] path_openat.isra.63+0xb8/0x4d0
 [<ffffffff81115a8e>] ? might_fault+0x4e/0xa0
 [<ffffffff8115f4f0>] do_filp_open+0x40/0x90
 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50
 [<ffffffff8116db85>] ? __alloc_fd+0xa5/0x1f0
 [<ffffffff8114e45f>] do_sys_open+0xef/0x1d0
 [<ffffffff8114e559>] SyS_open+0x19/0x20
 [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f
Code: 44 00 00 55 48 89 e5 41 57 49 89 ff 41 56 41 89 d6 41 55 41 54 4c 8d 67 18 53 48 83 ec 18 89 75 cc e9 f2 00 00 00 0f 1f 44 00 00 <48> 8b 80 40 03 00 00 48 89 df 4c 8b 68 58 e8 d5
a4 07 00 44 89
RIP  [<ffffffff8118b188>] __blkdev_get+0x28/0x450
 RSP <ffff88023e47dbd8>
CR2: 00000000000002b4
---[ end trace bb7f32dbf02398dc ]---

The brd change should be backported to stable kernels starting with 2.6.25.
The loop change should be backported to stable kernels starting with 2.6.22.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
turl referenced this issue in allwinner-dev-team/linux-allwinner Jan 28, 2014
Oprofile may crash in a KVM guest while unlaoding modules. This
happens if oprofile_arch_init() fails and oprofile switches to the hr
timer mode as a fallback. In this case oprofile_arch_exit() is called,
but it never was initialized properly which causes the crash. This
patch fixes this.

oprofile: using timer interrupt.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
PGD 41da3f067 PUD 41d80e067 PMD 0
Oops: 0002 [#1] PREEMPT SMP
CPU 5
Modules linked in: oprofile(-)

Pid: 2382, comm: modprobe Not tainted 3.1.0-rc7-00018-g709a39d torvalds#18 Advanced Micro Device Anaheim/Anaheim
RIP: 0010:[<ffffffff8123c226>]  [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
RSP: 0018:ffff88041de1de98  EFLAGS: 00010296
RAX: 0000000000000000 RBX: ffffffffa00060e0 RCX: dead000000200200
RDX: 0000000000000000 RSI: dead000000100100 RDI: ffffffff8178c620
RBP: ffff88041de1dea8 R08: 0000000000000001 R09: 0000000000000082
R10: 0000000000000000 R11: ffff88041de1dde8 R12: 0000000000000080
R13: fffffffffffffff5 R14: 0000000000000001 R15: 0000000000610210
FS:  00007f9ae5bef700(0000) GS:ffff88042fd40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000008 CR3: 000000041ca44000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process modprobe (pid: 2382, threadinfo ffff88041de1c000, task ffff88042db6d040)
Stack:
 ffff88041de1deb8 ffffffffa0006770 ffff88041de1deb8 ffffffffa000251e
 ffff88041de1dec8 ffffffffa00022c2 ffff88041de1ded8 ffffffffa0004993
 ffff88041de1df78 ffffffff81073115 656c69666f72706f 0000000000610200
Call Trace:
 [<ffffffffa000251e>] op_nmi_exit+0x15/0x17 [oprofile]
 [<ffffffffa00022c2>] oprofile_arch_exit+0xe/0x10 [oprofile]
 [<ffffffffa0004993>] oprofile_exit+0x13/0x15 [oprofile]
 [<ffffffff81073115>] sys_delete_module+0x1c3/0x22f
 [<ffffffff811bf09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff8148070b>] system_call_fastpath+0x16/0x1b
Code: 20 c6 78 81 e8 c5 cc 23 00 48 8b 13 48 8b 43 08 48 be 00 01 10 00 00 00 ad de 48 b9 00 02 20 00 00 00 ad de 48 c7 c7 20 c6 78 81
 89 42 08 48 89 10 48 89 33 48 89 4b 08 e8 a6 c0 23 00 5a 5b
RIP  [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
 RSP <ffff88041de1de98>
CR2: 0000000000000008
---[ end trace 06d4e95b6aa3b437 ]---

CC: stable@kernel.org # 2.6.37+
Signed-off-by: Robert Richter <robert.richter@amd.com>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Nov 29, 2021
Possible recursive locking is detected by lockdep when SMC
falls back to TCP. The corresponding warnings are as follows:

 ============================================
 WARNING: possible recursive locking detected
 5.16.0-rc1+ linux-sunxi#18 Tainted: G            E
 --------------------------------------------
 wrk/1391 is trying to acquire lock:
 ffff975246c8e7d8 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0x109/0x250 [smc]

 but task is already holding lock:
 ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&ei->socket.wq.wait);
   lock(&ei->socket.wq.wait);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 2 locks held by wrk/1391:
  #0: ffff975246040130 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_connect+0x43/0x150 [smc]
  #1: ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 stack backtrace:
 Call Trace:
  <TASK>
  dump_stack_lvl+0x56/0x7b
  __lock_acquire+0x951/0x11f0
  lock_acquire+0x27a/0x320
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  ? smc_switch_to_fallback+0xfe/0x250 [smc]
  _raw_spin_lock_irq+0x3b/0x80
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  smc_switch_to_fallback+0x109/0x250 [smc]
  smc_connect_fallback+0xe/0x30 [smc]
  __smc_connect+0xcf/0x1090 [smc]
  ? mark_held_locks+0x61/0x80
  ? __local_bh_enable_ip+0x77/0xe0
  ? lockdep_hardirqs_on+0xbf/0x130
  ? smc_connect+0x12a/0x150 [smc]
  smc_connect+0x12a/0x150 [smc]
  __sys_connect+0x8a/0xc0
  ? syscall_enter_from_user_mode+0x20/0x70
  __x64_sys_connect+0x16/0x20
  do_syscall_64+0x34/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The nested locking in smc_switch_to_fallback() is considered to
possibly cause a deadlock because smc_wait->lock and clc_wait->lock
are the same type of lock. But actually it is safe so far since
there is no other place trying to obtain smc_wait->lock when
clc_wait->lock is held. So the patch replaces spin_lock() with
spin_lock_nested() to avoid false report by lockdep.

Link: https://lkml.org/lkml/2021/11/19/962
Fixes: 2153bd1 ("Transfer remaining wait queue entries during fallback")
Reported-by: syzbot+e979d3597f48262cb4ee@syzkaller.appspotmail.com
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Acked-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Dec 20, 2021
[ Upstream commit 7a61432 ]

Possible recursive locking is detected by lockdep when SMC
falls back to TCP. The corresponding warnings are as follows:

 ============================================
 WARNING: possible recursive locking detected
 5.16.0-rc1+ linux-sunxi#18 Tainted: G            E
 --------------------------------------------
 wrk/1391 is trying to acquire lock:
 ffff975246c8e7d8 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0x109/0x250 [smc]

 but task is already holding lock:
 ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&ei->socket.wq.wait);
   lock(&ei->socket.wq.wait);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 2 locks held by wrk/1391:
  #0: ffff975246040130 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_connect+0x43/0x150 [smc]
  jwrdegoede#1: ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 stack backtrace:
 Call Trace:
  <TASK>
  dump_stack_lvl+0x56/0x7b
  __lock_acquire+0x951/0x11f0
  lock_acquire+0x27a/0x320
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  ? smc_switch_to_fallback+0xfe/0x250 [smc]
  _raw_spin_lock_irq+0x3b/0x80
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  smc_switch_to_fallback+0x109/0x250 [smc]
  smc_connect_fallback+0xe/0x30 [smc]
  __smc_connect+0xcf/0x1090 [smc]
  ? mark_held_locks+0x61/0x80
  ? __local_bh_enable_ip+0x77/0xe0
  ? lockdep_hardirqs_on+0xbf/0x130
  ? smc_connect+0x12a/0x150 [smc]
  smc_connect+0x12a/0x150 [smc]
  __sys_connect+0x8a/0xc0
  ? syscall_enter_from_user_mode+0x20/0x70
  __x64_sys_connect+0x16/0x20
  do_syscall_64+0x34/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The nested locking in smc_switch_to_fallback() is considered to
possibly cause a deadlock because smc_wait->lock and clc_wait->lock
are the same type of lock. But actually it is safe so far since
there is no other place trying to obtain smc_wait->lock when
clc_wait->lock is held. So the patch replaces spin_lock() with
spin_lock_nested() to avoid false report by lockdep.

Link: https://lkml.org/lkml/2021/11/19/962
Fixes: 2153bd1 ("Transfer remaining wait queue entries during fallback")
Reported-by: syzbot+e979d3597f48262cb4ee@syzkaller.appspotmail.com
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Acked-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Mar 26, 2022
[ Upstream commit 4224cfd ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     linux-sunxi#9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    linux-sunxi#10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    linux-sunxi#11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    linux-sunxi#12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    linux-sunxi#13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    linux-sunxi#14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    linux-sunxi#15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    linux-sunxi#16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    linux-sunxi#17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    linux-sunxi#18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    linux-sunxi#19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    linux-sunxi#20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    linux-sunxi#21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    linux-sunxi#22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    linux-sunxi#23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    linux-sunxi#24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    linux-sunxi#25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    linux-sunxi#26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <suresh2514@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 9, 2022
[ Upstream commit bf0cd60 ]

AV/C deferred transaction was supported at a commit 00a7bb8 ("ALSA:
firewire-lib: Add support for deferred transaction") while 'deferrable'
flag can be uninitialized for non-control/notify AV/C transactions.
UBSAN reports it:

kernel: ================================================================================
kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9
kernel: load of value 158 is not a valid value for type '_Bool'
kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P           OE     5.15.0-18-generic linux-sunxi#18-Ubuntu
kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019
kernel: Call Trace:
kernel:  <IRQ>
kernel:  show_stack+0x52/0x58
kernel:  dump_stack_lvl+0x4a/0x5f
kernel:  dump_stack+0x10/0x12
kernel:  ubsan_epilogue+0x9/0x45
kernel:  __ubsan_handle_load_invalid_value.cold+0x44/0x49
kernel:  fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]
kernel:  fcp_response+0x28/0x30 [snd_firewire_lib]
kernel:  fw_core_handle_request+0x230/0x3d0 [firewire_core]
kernel:  handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? transmit_complete_callback+0x9f/0x120 [firewire_core]
kernel:  ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]
kernel:  tasklet_action_common.constprop.0+0xea/0xf0
kernel:  tasklet_action+0x22/0x30
kernel:  __do_softirq+0xd9/0x2e3
kernel:  ? irq_finalize_oneshot.part.0+0xf0/0xf0
kernel:  do_softirq+0x75/0xa0
kernel:  </IRQ>
kernel:  <TASK>
kernel:  __local_bh_enable_ip+0x50/0x60
kernel:  irq_forced_thread_fn+0x7e/0x90
kernel:  irq_thread+0xba/0x190
kernel:  ? irq_thread_fn+0x60/0x60
kernel:  kthread+0x11e/0x140
kernel:  ? irq_thread_check_affinity+0xf0/0xf0
kernel:  ? set_kthread_struct+0x50/0x50
kernel:  ret_from_fork+0x22/0x30
kernel:  </TASK>
kernel: ================================================================================

This commit fixes the bug. The bug has no disadvantage for the non-
control/notify AV/C transactions since the flag has an effect for AV/C
response with INTERIM (0x0f) status which is not used for the transactions
in AV/C general specification.

Fixes: 00a7bb8 ("ALSA: firewire-lib: Add support for deferred transaction")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20220304125647.78430-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 17, 2022
[ Upstream commit 577298e ]

Even if it is only a false-positive since skip_buf0/skip_buf1 are only
used in mt76_dma_tx_cleanup_idx routine, initialize skip_unmap in
mt76_dma_rx_fill in order to fix the following UBSAN report:

[   13.924906] UBSAN: invalid-load in linux-5.15.0/drivers/net/wireless/mediatek/mt76/dma.c:162:13
[   13.924909] load of value 225 is not a valid value for type '_Bool'
[   13.924912] CPU: 9 PID: 672 Comm: systemd-udevd Not tainted 5.15.0-18-generic linux-sunxi#18-Ubuntu
[   13.924914] Hardware name: LENOVO 21A0000CMX/21A0000CMX, BIOS R1MET43W (1.13 ) 11/05/2021
[   13.924915] Call Trace:
[   13.924917]  <TASK>
[   13.924920]  show_stack+0x52/0x58
[   13.924925]  dump_stack_lvl+0x4a/0x5f
[   13.924931]  dump_stack+0x10/0x12
[   13.924932]  ubsan_epilogue+0x9/0x45
[   13.924934]  __ubsan_handle_load_invalid_value.cold+0x44/0x49
[   13.924935]  ? __iommu_dma_map+0x84/0xf0
[   13.924939]  mt76_dma_add_buf.constprop.0.cold+0x23/0x85 [mt76]
[   13.924949]  mt76_dma_rx_fill.isra.0+0x102/0x1f0 [mt76]
[   13.924954]  mt76_dma_init+0xc9/0x150 [mt76]
[   13.924959]  ? mt7921_dma_enable+0x110/0x110 [mt7921e]
[   13.924966]  mt7921_dma_init+0x1e3/0x260 [mt7921e]
[   13.924970]  mt7921_register_device+0x29d/0x510 [mt7921e]
[   13.924975]  mt7921_pci_probe.part.0+0x17f/0x1b0 [mt7921e]
[   13.924980]  mt7921_pci_probe+0x43/0x60 [mt7921e]
[   13.924984]  local_pci_probe+0x4b/0x90
[   13.924987]  pci_device_probe+0x115/0x1f0
[   13.924989]  really_probe+0x21e/0x420
[   13.924992]  __driver_probe_device+0x115/0x190
[   13.924994]  driver_probe_device+0x23/0xc0
[   13.924996]  __driver_attach+0xbd/0x1d0
[   13.924998]  ? __device_attach_driver+0x110/0x110
[   13.924999]  bus_for_each_dev+0x7e/0xc0
[   13.925001]  driver_attach+0x1e/0x20
[   13.925003]  bus_add_driver+0x135/0x200
[   13.925005]  driver_register+0x95/0xf0
[   13.925008]  ? 0xffffffffc0766000
[   13.925010]  __pci_register_driver+0x68/0x70
[   13.925011]  mt7921_pci_driver_init+0x23/0x1000 [mt7921e]
[   13.925015]  do_one_initcall+0x48/0x1d0
[   13.925019]  ? kmem_cache_alloc_trace+0x19e/0x2e0
[   13.925022]  do_init_module+0x62/0x280
[   13.925025]  load_module+0xac9/0xbb0
[   13.925027]  __do_sys_finit_module+0xbf/0x120
[   13.925029]  __x64_sys_finit_module+0x18/0x20
[   13.925030]  do_syscall_64+0x5c/0xc0
[   13.925033]  ? do_syscall_64+0x69/0xc0
[   13.925034]  ? sysvec_reschedule_ipi+0x78/0xe0
[   13.925036]  ? asm_sysvec_reschedule_ipi+0xa/0x20
[   13.925039]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   13.925040] RIP: 0033:0x7fbf2b90f94d
[   13.925045] RSP: 002b:00007ffe2ec7e5d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[   13.925047] RAX: ffffffffffffffda RBX: 000056106b0634e0 RCX: 00007fbf2b90f94d
[   13.925048] RDX: 0000000000000000 RSI: 00007fbf2baa3441 RDI: 0000000000000013
[   13.925049] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000002
[   13.925050] R10: 0000000000000013 R11: 0000000000000246 R12: 00007fbf2baa3441
[   13.925051] R13: 000056106b062620 R14: 000056106b0610c0 R15: 000056106b0640d0
[   13.925053]  </TASK>

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 25, 2022
[ Upstream commit bf0cd60 ]

AV/C deferred transaction was supported at a commit 00a7bb8 ("ALSA:
firewire-lib: Add support for deferred transaction") while 'deferrable'
flag can be uninitialized for non-control/notify AV/C transactions.
UBSAN reports it:

kernel: ================================================================================
kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9
kernel: load of value 158 is not a valid value for type '_Bool'
kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P           OE     5.15.0-18-generic linux-sunxi#18-Ubuntu
kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019
kernel: Call Trace:
kernel:  <IRQ>
kernel:  show_stack+0x52/0x58
kernel:  dump_stack_lvl+0x4a/0x5f
kernel:  dump_stack+0x10/0x12
kernel:  ubsan_epilogue+0x9/0x45
kernel:  __ubsan_handle_load_invalid_value.cold+0x44/0x49
kernel:  fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]
kernel:  fcp_response+0x28/0x30 [snd_firewire_lib]
kernel:  fw_core_handle_request+0x230/0x3d0 [firewire_core]
kernel:  handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? transmit_complete_callback+0x9f/0x120 [firewire_core]
kernel:  ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]
kernel:  tasklet_action_common.constprop.0+0xea/0xf0
kernel:  tasklet_action+0x22/0x30
kernel:  __do_softirq+0xd9/0x2e3
kernel:  ? irq_finalize_oneshot.part.0+0xf0/0xf0
kernel:  do_softirq+0x75/0xa0
kernel:  </IRQ>
kernel:  <TASK>
kernel:  __local_bh_enable_ip+0x50/0x60
kernel:  irq_forced_thread_fn+0x7e/0x90
kernel:  irq_thread+0xba/0x190
kernel:  ? irq_thread_fn+0x60/0x60
kernel:  kthread+0x11e/0x140
kernel:  ? irq_thread_check_affinity+0xf0/0xf0
kernel:  ? set_kthread_struct+0x50/0x50
kernel:  ret_from_fork+0x22/0x30
kernel:  </TASK>
kernel: ================================================================================

This commit fixes the bug. The bug has no disadvantage for the non-
control/notify AV/C transactions since the flag has an effect for AV/C
response with INTERIM (0x0f) status which is not used for the transactions
in AV/C general specification.

Fixes: 00a7bb8 ("ALSA: firewire-lib: Add support for deferred transaction")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20220304125647.78430-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 25, 2022
[ Upstream commit 577298e ]

Even if it is only a false-positive since skip_buf0/skip_buf1 are only
used in mt76_dma_tx_cleanup_idx routine, initialize skip_unmap in
mt76_dma_rx_fill in order to fix the following UBSAN report:

[   13.924906] UBSAN: invalid-load in linux-5.15.0/drivers/net/wireless/mediatek/mt76/dma.c:162:13
[   13.924909] load of value 225 is not a valid value for type '_Bool'
[   13.924912] CPU: 9 PID: 672 Comm: systemd-udevd Not tainted 5.15.0-18-generic linux-sunxi#18-Ubuntu
[   13.924914] Hardware name: LENOVO 21A0000CMX/21A0000CMX, BIOS R1MET43W (1.13 ) 11/05/2021
[   13.924915] Call Trace:
[   13.924917]  <TASK>
[   13.924920]  show_stack+0x52/0x58
[   13.924925]  dump_stack_lvl+0x4a/0x5f
[   13.924931]  dump_stack+0x10/0x12
[   13.924932]  ubsan_epilogue+0x9/0x45
[   13.924934]  __ubsan_handle_load_invalid_value.cold+0x44/0x49
[   13.924935]  ? __iommu_dma_map+0x84/0xf0
[   13.924939]  mt76_dma_add_buf.constprop.0.cold+0x23/0x85 [mt76]
[   13.924949]  mt76_dma_rx_fill.isra.0+0x102/0x1f0 [mt76]
[   13.924954]  mt76_dma_init+0xc9/0x150 [mt76]
[   13.924959]  ? mt7921_dma_enable+0x110/0x110 [mt7921e]
[   13.924966]  mt7921_dma_init+0x1e3/0x260 [mt7921e]
[   13.924970]  mt7921_register_device+0x29d/0x510 [mt7921e]
[   13.924975]  mt7921_pci_probe.part.0+0x17f/0x1b0 [mt7921e]
[   13.924980]  mt7921_pci_probe+0x43/0x60 [mt7921e]
[   13.924984]  local_pci_probe+0x4b/0x90
[   13.924987]  pci_device_probe+0x115/0x1f0
[   13.924989]  really_probe+0x21e/0x420
[   13.924992]  __driver_probe_device+0x115/0x190
[   13.924994]  driver_probe_device+0x23/0xc0
[   13.924996]  __driver_attach+0xbd/0x1d0
[   13.924998]  ? __device_attach_driver+0x110/0x110
[   13.924999]  bus_for_each_dev+0x7e/0xc0
[   13.925001]  driver_attach+0x1e/0x20
[   13.925003]  bus_add_driver+0x135/0x200
[   13.925005]  driver_register+0x95/0xf0
[   13.925008]  ? 0xffffffffc0766000
[   13.925010]  __pci_register_driver+0x68/0x70
[   13.925011]  mt7921_pci_driver_init+0x23/0x1000 [mt7921e]
[   13.925015]  do_one_initcall+0x48/0x1d0
[   13.925019]  ? kmem_cache_alloc_trace+0x19e/0x2e0
[   13.925022]  do_init_module+0x62/0x280
[   13.925025]  load_module+0xac9/0xbb0
[   13.925027]  __do_sys_finit_module+0xbf/0x120
[   13.925029]  __x64_sys_finit_module+0x18/0x20
[   13.925030]  do_syscall_64+0x5c/0xc0
[   13.925033]  ? do_syscall_64+0x69/0xc0
[   13.925034]  ? sysvec_reschedule_ipi+0x78/0xe0
[   13.925036]  ? asm_sysvec_reschedule_ipi+0xa/0x20
[   13.925039]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   13.925040] RIP: 0033:0x7fbf2b90f94d
[   13.925045] RSP: 002b:00007ffe2ec7e5d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[   13.925047] RAX: ffffffffffffffda RBX: 000056106b0634e0 RCX: 00007fbf2b90f94d
[   13.925048] RDX: 0000000000000000 RSI: 00007fbf2baa3441 RDI: 0000000000000013
[   13.925049] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000002
[   13.925050] R10: 0000000000000013 R11: 0000000000000246 R12: 00007fbf2baa3441
[   13.925051] R13: 000056106b062620 R14: 000056106b0610c0 R15: 000056106b0640d0
[   13.925053]  </TASK>

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jun 10, 2022
commit 2a4a62a upstream.

syscall_stub_data() expects the data_count parameter to be the number of
longs, not bytes.

 ==================================================================
 BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0
 Read of size 128 at addr 000000006411f6f0 by task swapper/1

 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ linux-sunxi#18
 Call Trace:
  show_stack.cold+0x166/0x2a7
  __dump_stack+0x3a/0x43
  dump_stack_lvl+0x1f/0x27
  print_report.cold+0xdb/0xf81
  kasan_report+0x119/0x1f0
  kasan_check_range+0x3a3/0x440
  memcpy+0x52/0x140
  syscall_stub_data+0x70/0xe0
  write_ldt_entry+0xac/0x190
  init_new_ldt+0x515/0x960
  init_new_context+0x2c4/0x4d0
  mm_init.constprop.0+0x5ed/0x760
  mm_alloc+0x118/0x170
  0x60033f48
  do_one_initcall+0x1d7/0x860
  0x60003e7b
  kernel_init+0x6e/0x3d4
  new_thread_handler+0x1e7/0x2c0

 The buggy address belongs to stack of task swapper/1
  and is located at offset 64 in frame:
  init_new_ldt+0x0/0x960

 This frame has 2 objects:
  [32, 40) 'addr'
  [64, 80) 'desc'
 ==================================================================

Fixes: 858259c ("uml: maintain own LDT entries")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Nov 21, 2022
In __unregister_kprobe_top(), if the currently unregistered probe has
post_handler but other child probes of the aggrprobe do not have
post_handler, the post_handler of the aggrprobe is cleared. If this is
a ftrace-based probe, there is a problem. In later calls to
disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is
NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in
__disarm_kprobe_ftrace() and may even cause use-after-free:

  Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2)
  WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0
  Modules linked in: testKprobe_007(-)
  CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty linux-sunxi#18
  [...]
  Call Trace:
   <TASK>
   __disable_kprobe+0xcd/0xe0
   __unregister_kprobe_top+0x12/0x150
   ? mutex_lock+0xe/0x30
   unregister_kprobes.part.23+0x31/0xa0
   unregister_kprobe+0x32/0x40
   __x64_sys_delete_module+0x15e/0x260
   ? do_user_addr_fault+0x2cd/0x6b0
   do_syscall_64+0x3a/0x90
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   [...]

For the kprobe-on-ftrace case, we keep the post_handler setting to
identify this aggrprobe armed with kprobe_ipmodify_ops. This way we
can disarm it correctly.

Link: https://lore.kernel.org/all/20221112070000.35299-1-lihuafei1@huawei.com/

Fixes: 0bc11ed ("kprobes: Allow kprobes coexist with livepatch")
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Dec 14, 2022
[ Upstream commit 5dd7caf ]

In __unregister_kprobe_top(), if the currently unregistered probe has
post_handler but other child probes of the aggrprobe do not have
post_handler, the post_handler of the aggrprobe is cleared. If this is
a ftrace-based probe, there is a problem. In later calls to
disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is
NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in
__disarm_kprobe_ftrace() and may even cause use-after-free:

  Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2)
  WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0
  Modules linked in: testKprobe_007(-)
  CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty linux-sunxi#18
  [...]
  Call Trace:
   <TASK>
   __disable_kprobe+0xcd/0xe0
   __unregister_kprobe_top+0x12/0x150
   ? mutex_lock+0xe/0x30
   unregister_kprobes.part.23+0x31/0xa0
   unregister_kprobe+0x32/0x40
   __x64_sys_delete_module+0x15e/0x260
   ? do_user_addr_fault+0x2cd/0x6b0
   do_syscall_64+0x3a/0x90
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   [...]

For the kprobe-on-ftrace case, we keep the post_handler setting to
identify this aggrprobe armed with kprobe_ipmodify_ops. This way we
can disarm it correctly.

Link: https://lore.kernel.org/all/20221112070000.35299-1-lihuafei1@huawei.com/

Fixes: 0bc11ed ("kprobes: Allow kprobes coexist with livepatch")
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jan 5, 2023
…g the sock

[ Upstream commit 3cf7203 ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   jwrdegoede#1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   jwrdegoede#2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   jwrdegoede#3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   jwrdegoede#4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   jwrdegoede#5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   jwrdegoede#6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   linux-sunxi#7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   linux-sunxi#8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   linux-sunxi#9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  linux-sunxi#10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  linux-sunxi#11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  linux-sunxi#12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  linux-sunxi#13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  linux-sunxi#14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  linux-sunxi#15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  linux-sunxi#16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  linux-sunxi#17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  linux-sunxi#18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jan 5, 2023
[ Upstream commit b6702a9 ]

syzkaller reported use-after-free with the stack trace like below [1]:

[   38.960489][    C3] ==================================================================
[   38.963216][    C3] BUG: KASAN: use-after-free in ar5523_cmd_tx_cb+0x220/0x240
[   38.964950][    C3] Read of size 8 at addr ffff888048e03450 by task swapper/3/0
[   38.966363][    C3]
[   38.967053][    C3] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.0.0-09039-ga6afa4199d3d-dirty linux-sunxi#18
[   38.968464][    C3] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
[   38.969959][    C3] Call Trace:
[   38.970841][    C3]  <IRQ>
[   38.971663][    C3]  dump_stack_lvl+0xfc/0x174
[   38.972620][    C3]  print_report.cold+0x2c3/0x752
[   38.973626][    C3]  ? ar5523_cmd_tx_cb+0x220/0x240
[   38.974644][    C3]  kasan_report+0xb1/0x1d0
[   38.975720][    C3]  ? ar5523_cmd_tx_cb+0x220/0x240
[   38.976831][    C3]  ar5523_cmd_tx_cb+0x220/0x240
[   38.978412][    C3]  __usb_hcd_giveback_urb+0x353/0x5b0
[   38.979755][    C3]  usb_hcd_giveback_urb+0x385/0x430
[   38.981266][    C3]  dummy_timer+0x140c/0x34e0
[   38.982925][    C3]  ? notifier_call_chain+0xb5/0x1e0
[   38.984761][    C3]  ? rcu_read_lock_sched_held+0xb/0x60
[   38.986242][    C3]  ? lock_release+0x51c/0x790
[   38.987323][    C3]  ? _raw_read_unlock_irqrestore+0x37/0x70
[   38.988483][    C3]  ? __wake_up_common_lock+0xde/0x130
[   38.989621][    C3]  ? reacquire_held_locks+0x4a0/0x4a0
[   38.990777][    C3]  ? lock_acquire+0x472/0x550
[   38.991919][    C3]  ? rcu_read_lock_sched_held+0xb/0x60
[   38.993138][    C3]  ? lock_acquire+0x472/0x550
[   38.994890][    C3]  ? dummy_urb_enqueue+0x860/0x860
[   38.996266][    C3]  ? do_raw_spin_unlock+0x16f/0x230
[   38.997670][    C3]  ? dummy_urb_enqueue+0x860/0x860
[   38.999116][    C3]  call_timer_fn+0x1a0/0x6a0
[   39.000668][    C3]  ? add_timer_on+0x4a0/0x4a0
[   39.002137][    C3]  ? reacquire_held_locks+0x4a0/0x4a0
[   39.003809][    C3]  ? __next_timer_interrupt+0x226/0x2a0
[   39.005509][    C3]  __run_timers.part.0+0x69a/0xac0
[   39.007025][    C3]  ? dummy_urb_enqueue+0x860/0x860
[   39.008716][    C3]  ? call_timer_fn+0x6a0/0x6a0
[   39.010254][    C3]  ? cpuacct_percpu_seq_show+0x10/0x10
[   39.011795][    C3]  ? kvm_sched_clock_read+0x14/0x40
[   39.013277][    C3]  ? sched_clock_cpu+0x69/0x2b0
[   39.014724][    C3]  run_timer_softirq+0xb6/0x1d0
[   39.016196][    C3]  __do_softirq+0x1d2/0x9be
[   39.017616][    C3]  __irq_exit_rcu+0xeb/0x190
[   39.019004][    C3]  irq_exit_rcu+0x5/0x20
[   39.020361][    C3]  sysvec_apic_timer_interrupt+0x8f/0xb0
[   39.021965][    C3]  </IRQ>
[   39.023237][    C3]  <TASK>

In ar5523_probe(), ar5523_host_available() calls ar5523_cmd() as below
(there are other functions which finally call ar5523_cmd()):

ar5523_probe()
-> ar5523_host_available()
   -> ar5523_cmd_read()
      -> ar5523_cmd()

If ar5523_cmd() timed out, then ar5523_host_available() failed and
ar5523_probe() freed the device structure.  So, ar5523_cmd_tx_cb()
might touch the freed structure.

This patch fixes this issue by canceling in-flight tx cmd if submitted
urb timed out.

Link: https://syzkaller.appspot.com/bug?id=9e12b2d54300842b71bdd18b54971385ff0d0d3a [1]
Reported-by: syzbot+95001b1fd6dfcc716c29@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20221009183223.420015-1-syoshida@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jan 19, 2023
The inline assembly for arm64's cmpxchg_double*() implementations use a
+Q constraint to hazard against other accesses to the memory location
being exchanged. However, the pointer passed to the constraint is a
pointer to unsigned long, and thus the hazard only applies to the first
8 bytes of the location.

GCC can take advantage of this, assuming that other portions of the
location are unchanged, leading to a number of potential problems.

This is similar to what we fixed back in commit:

  fee960b ("arm64: xchg: hazard against entire exchange variable")

... but we forgot to adjust cmpxchg_double*() similarly at the same
time.

The same problem applies, as demonstrated with the following test:

| struct big {
|         u64 lo, hi;
| } __aligned(128);
|
| unsigned long foo(struct big *b)
| {
|         u64 hi_old, hi_new;
|
|         hi_old = b->hi;
|         cmpxchg_double_local(&b->lo, &b->hi, 0x12, 0x34, 0x56, 0x78);
|         hi_new = b->hi;
|
|         return hi_old ^ hi_new;
| }

... which GCC 12.1.0 compiles as:

| 0000000000000000 <foo>:
|    0:   d503233f        paciasp
|    4:   aa0003e4        mov     x4, x0
|    8:   1400000e        b       40 <foo+0x40>
|    c:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   10:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   14:   aa0003e5        mov     x5, x0
|   18:   aa0103e6        mov     x6, x1
|   1c:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   20:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   24:   48207c82        casp    x0, x1, x2, x3, [x4]
|   28:   ca050000        eor     x0, x0, x5
|   2c:   ca060021        eor     x1, x1, x6
|   30:   aa010000        orr     x0, x0, x1
|   34:   d2800000        mov     x0, #0x0                        // #0    <--- BANG
|   38:   d50323bf        autiasp
|   3c:   d65f03c0        ret
|   40:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   44:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   48:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   4c:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   50:   f9800091        prfm    pstl1strm, [x4]
|   54:   c87f1885        ldxp    x5, x6, [x4]
|   58:   ca0000a5        eor     x5, x5, x0
|   5c:   ca0100c6        eor     x6, x6, x1
|   60:   aa0600a6        orr     x6, x5, x6
|   64:   b5000066        cbnz    x6, 70 <foo+0x70>
|   68:   c8250c82        stxp    w5, x2, x3, [x4]
|   6c:   35ffff45        cbnz    w5, 54 <foo+0x54>
|   70:   d2800000        mov     x0, #0x0                        // #0     <--- BANG
|   74:   d50323bf        autiasp
|   78:   d65f03c0        ret

Notice that at the lines with "BANG" comments, GCC has assumed that the
higher 8 bytes are unchanged by the cmpxchg_double() call, and that
`hi_old ^ hi_new` can be reduced to a constant zero, for both LSE and
LL/SC versions of cmpxchg_double().

This patch fixes the issue by passing a pointer to __uint128_t into the
+Q constraint, ensuring that the compiler hazards against the entire 16
bytes being modified.

With this change, GCC 12.1.0 compiles the above test as:

| 0000000000000000 <foo>:
|    0:   f9400407        ldr     x7, [x0, linux-sunxi#8]
|    4:   d503233f        paciasp
|    8:   aa0003e4        mov     x4, x0
|    c:   1400000f        b       48 <foo+0x48>
|   10:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   14:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   18:   aa0003e5        mov     x5, x0
|   1c:   aa0103e6        mov     x6, x1
|   20:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   24:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   28:   48207c82        casp    x0, x1, x2, x3, [x4]
|   2c:   ca050000        eor     x0, x0, x5
|   30:   ca060021        eor     x1, x1, x6
|   34:   aa010000        orr     x0, x0, x1
|   38:   f9400480        ldr     x0, [x4, linux-sunxi#8]
|   3c:   d50323bf        autiasp
|   40:   ca0000e0        eor     x0, x7, x0
|   44:   d65f03c0        ret
|   48:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   4c:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   50:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   54:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   58:   f9800091        prfm    pstl1strm, [x4]
|   5c:   c87f1885        ldxp    x5, x6, [x4]
|   60:   ca0000a5        eor     x5, x5, x0
|   64:   ca0100c6        eor     x6, x6, x1
|   68:   aa0600a6        orr     x6, x5, x6
|   6c:   b5000066        cbnz    x6, 78 <foo+0x78>
|   70:   c8250c82        stxp    w5, x2, x3, [x4]
|   74:   35ffff45        cbnz    w5, 5c <foo+0x5c>
|   78:   f9400480        ldr     x0, [x4, linux-sunxi#8]
|   7c:   d50323bf        autiasp
|   80:   ca0000e0        eor     x0, x7, x0
|   84:   d65f03c0        ret

... sampling the high 8 bytes before and after the cmpxchg, and
performing an EOR, as we'd expect.

For backporting, I've tested this atop linux-4.9.y with GCC 5.5.0. Note
that linux-4.9.y is oldest currently supported stable release, and
mandates GCC 5.1+. Unfortunately I couldn't get a GCC 5.1 binary to run
on my machines due to library incompatibilities.

I've also used a standalone test to check that we can use a __uint128_t
pointer in a +Q constraint at least as far back as GCC 4.8.5 and LLVM
3.9.1.

Fixes: 5284e1b ("arm64: xchg: Implement cmpxchg_double")
Fixes: e9a4b79 ("arm64: cmpxchg_dbl: patch in lse instructions when supported by the CPU")
Reported-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/lkml/Y6DEfQXymYVgL3oJ@boqun-archlinux/
Reported-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/Y6GXoO4qmH9OIZ5Q@hirez.programming.kicks-ass.net/
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230104151626.3262137-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jan 25, 2023
commit 031af50 upstream.

The inline assembly for arm64's cmpxchg_double*() implementations use a
+Q constraint to hazard against other accesses to the memory location
being exchanged. However, the pointer passed to the constraint is a
pointer to unsigned long, and thus the hazard only applies to the first
8 bytes of the location.

GCC can take advantage of this, assuming that other portions of the
location are unchanged, leading to a number of potential problems.

This is similar to what we fixed back in commit:

  fee960b ("arm64: xchg: hazard against entire exchange variable")

... but we forgot to adjust cmpxchg_double*() similarly at the same
time.

The same problem applies, as demonstrated with the following test:

| struct big {
|         u64 lo, hi;
| } __aligned(128);
|
| unsigned long foo(struct big *b)
| {
|         u64 hi_old, hi_new;
|
|         hi_old = b->hi;
|         cmpxchg_double_local(&b->lo, &b->hi, 0x12, 0x34, 0x56, 0x78);
|         hi_new = b->hi;
|
|         return hi_old ^ hi_new;
| }

... which GCC 12.1.0 compiles as:

| 0000000000000000 <foo>:
|    0:   d503233f        paciasp
|    4:   aa0003e4        mov     x4, x0
|    8:   1400000e        b       40 <foo+0x40>
|    c:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   10:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   14:   aa0003e5        mov     x5, x0
|   18:   aa0103e6        mov     x6, x1
|   1c:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   20:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   24:   48207c82        casp    x0, x1, x2, x3, [x4]
|   28:   ca050000        eor     x0, x0, x5
|   2c:   ca060021        eor     x1, x1, x6
|   30:   aa010000        orr     x0, x0, x1
|   34:   d2800000        mov     x0, #0x0                        // #0    <--- BANG
|   38:   d50323bf        autiasp
|   3c:   d65f03c0        ret
|   40:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   44:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   48:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   4c:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   50:   f9800091        prfm    pstl1strm, [x4]
|   54:   c87f1885        ldxp    x5, x6, [x4]
|   58:   ca0000a5        eor     x5, x5, x0
|   5c:   ca0100c6        eor     x6, x6, x1
|   60:   aa0600a6        orr     x6, x5, x6
|   64:   b5000066        cbnz    x6, 70 <foo+0x70>
|   68:   c8250c82        stxp    w5, x2, x3, [x4]
|   6c:   35ffff45        cbnz    w5, 54 <foo+0x54>
|   70:   d2800000        mov     x0, #0x0                        // #0     <--- BANG
|   74:   d50323bf        autiasp
|   78:   d65f03c0        ret

Notice that at the lines with "BANG" comments, GCC has assumed that the
higher 8 bytes are unchanged by the cmpxchg_double() call, and that
`hi_old ^ hi_new` can be reduced to a constant zero, for both LSE and
LL/SC versions of cmpxchg_double().

This patch fixes the issue by passing a pointer to __uint128_t into the
+Q constraint, ensuring that the compiler hazards against the entire 16
bytes being modified.

With this change, GCC 12.1.0 compiles the above test as:

| 0000000000000000 <foo>:
|    0:   f9400407        ldr     x7, [x0, linux-sunxi#8]
|    4:   d503233f        paciasp
|    8:   aa0003e4        mov     x4, x0
|    c:   1400000f        b       48 <foo+0x48>
|   10:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   14:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   18:   aa0003e5        mov     x5, x0
|   1c:   aa0103e6        mov     x6, x1
|   20:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   24:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   28:   48207c82        casp    x0, x1, x2, x3, [x4]
|   2c:   ca050000        eor     x0, x0, x5
|   30:   ca060021        eor     x1, x1, x6
|   34:   aa010000        orr     x0, x0, x1
|   38:   f9400480        ldr     x0, [x4, linux-sunxi#8]
|   3c:   d50323bf        autiasp
|   40:   ca0000e0        eor     x0, x7, x0
|   44:   d65f03c0        ret
|   48:   d2800240        mov     x0, #0x12                       // linux-sunxi#18
|   4c:   d2800681        mov     x1, #0x34                       // linux-sunxi#52
|   50:   d2800ac2        mov     x2, #0x56                       // linux-sunxi#86
|   54:   d2800f03        mov     x3, #0x78                       // linux-sunxi#120
|   58:   f9800091        prfm    pstl1strm, [x4]
|   5c:   c87f1885        ldxp    x5, x6, [x4]
|   60:   ca0000a5        eor     x5, x5, x0
|   64:   ca0100c6        eor     x6, x6, x1
|   68:   aa0600a6        orr     x6, x5, x6
|   6c:   b5000066        cbnz    x6, 78 <foo+0x78>
|   70:   c8250c82        stxp    w5, x2, x3, [x4]
|   74:   35ffff45        cbnz    w5, 5c <foo+0x5c>
|   78:   f9400480        ldr     x0, [x4, linux-sunxi#8]
|   7c:   d50323bf        autiasp
|   80:   ca0000e0        eor     x0, x7, x0
|   84:   d65f03c0        ret

... sampling the high 8 bytes before and after the cmpxchg, and
performing an EOR, as we'd expect.

For backporting, I've tested this atop linux-4.9.y with GCC 5.5.0. Note
that linux-4.9.y is oldest currently supported stable release, and
mandates GCC 5.1+. Unfortunately I couldn't get a GCC 5.1 binary to run
on my machines due to library incompatibilities.

I've also used a standalone test to check that we can use a __uint128_t
pointer in a +Q constraint at least as far back as GCC 4.8.5 and LLVM
3.9.1.

Fixes: 5284e1b ("arm64: xchg: Implement cmpxchg_double")
Fixes: e9a4b79 ("arm64: cmpxchg_dbl: patch in lse instructions when supported by the CPU")
Reported-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/lkml/Y6DEfQXymYVgL3oJ@boqun-archlinux/
Reported-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/Y6GXoO4qmH9OIZ5Q@hirez.programming.kicks-ass.net/
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230104151626.3262137-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 1, 2023
[ Upstream commit 4e264be ]

When a system with E810 with existing VFs gets rebooted the following
hang may be observed.

 Pid 1 is hung in iavf_remove(), part of a network driver:
 PID: 1        TASK: ffff965400e5a340  CPU: 24   COMMAND: "systemd-shutdow"
  #0 [ffffaad04005fa50] __schedule at ffffffff8b3239cb
  jwrdegoede#1 [ffffaad04005fae8] schedule at ffffffff8b323e2d
  jwrdegoede#2 [ffffaad04005fb00] schedule_hrtimeout_range_clock at ffffffff8b32cebc
  jwrdegoede#3 [ffffaad04005fb80] usleep_range_state at ffffffff8b32c930
  jwrdegoede#4 [ffffaad04005fbb0] iavf_remove at ffffffffc12b9b4c [iavf]
  jwrdegoede#5 [ffffaad04005fbf0] pci_device_remove at ffffffff8add7513
  jwrdegoede#6 [ffffaad04005fc10] device_release_driver_internal at ffffffff8af08baa
  linux-sunxi#7 [ffffaad04005fc40] pci_stop_bus_device at ffffffff8adcc5fc
  linux-sunxi#8 [ffffaad04005fc60] pci_stop_and_remove_bus_device at ffffffff8adcc81e
  linux-sunxi#9 [ffffaad04005fc70] pci_iov_remove_virtfn at ffffffff8adf9429
 linux-sunxi#10 [ffffaad04005fca8] sriov_disable at ffffffff8adf98e4
 linux-sunxi#11 [ffffaad04005fcc8] ice_free_vfs at ffffffffc04bb2c8 [ice]
 linux-sunxi#12 [ffffaad04005fd10] ice_remove at ffffffffc04778fe [ice]
 linux-sunxi#13 [ffffaad04005fd38] ice_shutdown at ffffffffc0477946 [ice]
 linux-sunxi#14 [ffffaad04005fd50] pci_device_shutdown at ffffffff8add58f1
 linux-sunxi#15 [ffffaad04005fd70] device_shutdown at ffffffff8af05386
 linux-sunxi#16 [ffffaad04005fd98] kernel_restart at ffffffff8a92a870
 linux-sunxi#17 [ffffaad04005fda8] __do_sys_reboot at ffffffff8a92abd6
 linux-sunxi#18 [ffffaad04005fee0] do_syscall_64 at ffffffff8b317159
 linux-sunxi#19 [ffffaad04005ff08] __context_tracking_enter at ffffffff8b31b6fc
 linux-sunxi#20 [ffffaad04005ff18] syscall_exit_to_user_mode at ffffffff8b31b50d
 linux-sunxi#21 [ffffaad04005ff28] do_syscall_64 at ffffffff8b317169
 linux-sunxi#22 [ffffaad04005ff50] entry_SYSCALL_64_after_hwframe at ffffffff8b40009b
     RIP: 00007f1baa5c13d7  RSP: 00007fffbcc55a98  RFLAGS: 00000202
     RAX: ffffffffffffffda  RBX: 0000000000000000  RCX: 00007f1baa5c13d7
     RDX: 0000000001234567  RSI: 0000000028121969  RDI: 00000000fee1dead
     RBP: 00007fffbcc55ca0   R8: 0000000000000000   R9: 00007fffbcc54e90
     R10: 00007fffbcc55050  R11: 0000000000000202  R12: 0000000000000005
     R13: 0000000000000000  R14: 00007fffbcc55af0  R15: 0000000000000000
     ORIG_RAX: 00000000000000a9  CS: 0033  SS: 002b

During reboot all drivers PM shutdown callbacks are invoked.
In iavf_shutdown() the adapter state is changed to __IAVF_REMOVE.
In ice_shutdown() the call chain above is executed, which at some point
calls iavf_remove(). However iavf_remove() expects the VF to be in one
of the states __IAVF_RUNNING, __IAVF_DOWN or __IAVF_INIT_FAILED. If
that's not the case it sleeps forever.
So if iavf_shutdown() gets invoked before iavf_remove() the system will
hang indefinitely because the adapter is already in state __IAVF_REMOVE.

Fix this by returning from iavf_remove() if the state is __IAVF_REMOVE,
as we already went through iavf_shutdown().

Fixes: 9745780 ("iavf: Add waiting so the port is initialized in remove")
Fixes: a841733 ("iavf: Fix race condition between iavf_shutdown and iavf_remove")
Reported-by: Marius Cornea <mcornea@redhat.com>
Signed-off-by: Stefan Assmann <sassmann@kpanic.de>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jun 12, 2023
The cited commit adds a compeletion to remove dependency on rtnl
lock. But it causes a deadlock for multiple encapsulations:

 crash> bt ffff8aece8a64000
 PID: 1514557  TASK: ffff8aece8a64000  CPU: 3    COMMAND: "tc"
  #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418
  #2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898
  #3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8
  #4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb
  #5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core]
  #6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core]
  linux-sunxi#7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core]
  linux-sunxi#8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core]
  linux-sunxi#9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core]
 linux-sunxi#10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core]
 linux-sunxi#11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core]
 linux-sunxi#12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8
 linux-sunxi#13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower]
 linux-sunxi#14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower]
 linux-sunxi#15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047
 linux-sunxi#16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31
 linux-sunxi#17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853
 linux-sunxi#18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835
 linux-sunxi#19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27
 linux-sunxi#20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245
 linux-sunxi#21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482
 linux-sunxi#22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a
 linux-sunxi#23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2
 linux-sunxi#24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2
 linux-sunxi#25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f
 linux-sunxi#26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8
 linux-sunxi#27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c
 crash> bt 0xffff8aeb07544000
 PID: 1110766  TASK: ffff8aeb07544000  CPU: 0    COMMAND: "kworker/u20:9"
  #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418
  #2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88
  #3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b
  #4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core]
  #5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core]
  #6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core]
  linux-sunxi#7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c
  linux-sunxi#8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012
  linux-sunxi#9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d
 linux-sunxi#10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f

After the first encap is attached, flow will be added to encap
entry's flows list. If neigh update is running at this time, the
following encaps of the flow can't hold the encap_tbl_lock and
sleep. If neigh update thread is waiting for that flow's init_done,
deadlock happens.

Fix it by holding lock outside of the for loop. If neigh update is
running, prevent encap flows from offloading. Since the lock is held
outside of the for loop, concurrent creation of encap entries is not
allowed. So remove unnecessary wait_for_completion call for res_ready.

Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
codekipper pushed a commit to codekipper/linux-sunxi that referenced this issue Jul 26, 2023
commit fc80fc2 upstream.

After the listener svc_sock is freed, and before invoking svc_tcp_accept()
for the established child sock, there is a window that the newsock
retaining a freed listener svc_sock in sk_user_data which cloning from
parent. In the race window, if data is received on the newsock, we will
observe use-after-free report in svc_tcp_listen_data_ready().

Reproduce by two tasks:

1. while :; do rpc.nfsd 0 ; rpc.nfsd; done
2. while :; do echo "" | ncat -4 127.0.0.1 2049 ; done

KASAN report:

  ==================================================================
  BUG: KASAN: slab-use-after-free in svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]
  Read of size 8 at addr ffff888139d96228 by task nc/102553
  CPU: 7 PID: 102553 Comm: nc Not tainted 6.3.0+ linux-sunxi#18
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x33/0x50
   print_address_description.constprop.0+0x27/0x310
   print_report+0x3e/0x70
   kasan_report+0xae/0xe0
   svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]
   tcp_data_queue+0x9f4/0x20e0
   tcp_rcv_established+0x666/0x1f60
   tcp_v4_do_rcv+0x51c/0x850
   tcp_v4_rcv+0x23fc/0x2e80
   ip_protocol_deliver_rcu+0x62/0x300
   ip_local_deliver_finish+0x267/0x350
   ip_local_deliver+0x18b/0x2d0
   ip_rcv+0x2fb/0x370
   __netif_receive_skb_one_core+0x166/0x1b0
   process_backlog+0x24c/0x5e0
   __napi_poll+0xa2/0x500
   net_rx_action+0x854/0xc90
   __do_softirq+0x1bb/0x5de
   do_softirq+0xcb/0x100
   </IRQ>
   <TASK>
   ...
   </TASK>

  Allocated by task 102371:
   kasan_save_stack+0x1e/0x40
   kasan_set_track+0x21/0x30
   __kasan_kmalloc+0x7b/0x90
   svc_setup_socket+0x52/0x4f0 [sunrpc]
   svc_addsock+0x20d/0x400 [sunrpc]
   __write_ports_addfd+0x209/0x390 [nfsd]
   write_ports+0x239/0x2c0 [nfsd]
   nfsctl_transaction_write+0xac/0x110 [nfsd]
   vfs_write+0x1c3/0xae0
   ksys_write+0xed/0x1c0
   do_syscall_64+0x38/0x90
   entry_SYSCALL_64_after_hwframe+0x72/0xdc

  Freed by task 102551:
   kasan_save_stack+0x1e/0x40
   kasan_set_track+0x21/0x30
   kasan_save_free_info+0x2a/0x50
   __kasan_slab_free+0x106/0x190
   __kmem_cache_free+0x133/0x270
   svc_xprt_free+0x1e2/0x350 [sunrpc]
   svc_xprt_destroy_all+0x25a/0x440 [sunrpc]
   nfsd_put+0x125/0x240 [nfsd]
   nfsd_svc+0x2cb/0x3c0 [nfsd]
   write_threads+0x1ac/0x2a0 [nfsd]
   nfsctl_transaction_write+0xac/0x110 [nfsd]
   vfs_write+0x1c3/0xae0
   ksys_write+0xed/0x1c0
   do_syscall_64+0x38/0x90
   entry_SYSCALL_64_after_hwframe+0x72/0xdc

Fix the UAF by simply doing nothing in svc_tcp_listen_data_ready()
if state != TCP_LISTEN, that will avoid dereferencing svsk for all
child socket.

Link: https://lore.kernel.org/lkml/20230507091131.23540-1-dinghui@sangfor.com.cn/
Fixes: fa9251a ("SUNRPC: Call the default socket callbacks instead of open coding")
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 20, 2023
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   linux-sunxi#10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   linux-sunxi#11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   linux-sunxi#12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   linux-sunxi#13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   linux-sunxi#14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   linux-sunxi#15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   linux-sunxi#16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   linux-sunxi#17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   linux-sunxi#18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   linux-sunxi#19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   linux-sunxi#20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   linux-sunxi#21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   linux-sunxi#22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   linux-sunxi#23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   linux-sunxi#24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   linux-sunxi#25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   linux-sunxi#26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   linux-sunxi#27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   linux-sunxi#10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   linux-sunxi#11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   linux-sunxi#12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   linux-sunxi#13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   linux-sunxi#14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   linux-sunxi#15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   linux-sunxi#16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   linux-sunxi#17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Oct 9, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  linux-sunxi#7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  linux-sunxi#8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  linux-sunxi#9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 linux-sunxi#10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 linux-sunxi#11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 linux-sunxi#12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 linux-sunxi#13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 linux-sunxi#14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 linux-sunxi#15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 linux-sunxi#16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 linux-sunxi#17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 linux-sunxi#18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 linux-sunxi#19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 linux-sunxi#20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Dec 13, 2023
[ Upstream commit e3e82fc ]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   jwrdegoede#1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   jwrdegoede#2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   jwrdegoede#3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   jwrdegoede#4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   jwrdegoede#5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   jwrdegoede#6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   linux-sunxi#7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   linux-sunxi#8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   linux-sunxi#9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   linux-sunxi#10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   linux-sunxi#11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   linux-sunxi#12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   linux-sunxi#13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   linux-sunxi#14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   linux-sunxi#15 [ffff88aa841efb88] device_del at ffffffff82179d23
   linux-sunxi#16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   linux-sunxi#17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   linux-sunxi#18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   linux-sunxi#19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   linux-sunxi#20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   linux-sunxi#21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn
Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com>
Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn>
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jan 19, 2024
[ Upstream commit 37c3b9f ]

The cited commit adds a compeletion to remove dependency on rtnl
lock. But it causes a deadlock for multiple encapsulations:

 crash> bt ffff8aece8a64000
 PID: 1514557  TASK: ffff8aece8a64000  CPU: 3    COMMAND: "tc"
  #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45
  jwrdegoede#1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418
  jwrdegoede#2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898
  jwrdegoede#3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8
  jwrdegoede#4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb
  jwrdegoede#5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core]
  jwrdegoede#6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core]
  linux-sunxi#7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core]
  linux-sunxi#8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core]
  linux-sunxi#9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core]
 linux-sunxi#10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core]
 linux-sunxi#11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core]
 linux-sunxi#12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8
 linux-sunxi#13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower]
 linux-sunxi#14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower]
 linux-sunxi#15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047
 linux-sunxi#16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31
 linux-sunxi#17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853
 linux-sunxi#18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835
 linux-sunxi#19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27
 linux-sunxi#20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245
 linux-sunxi#21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482
 linux-sunxi#22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a
 linux-sunxi#23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2
 linux-sunxi#24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2
 linux-sunxi#25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f
 linux-sunxi#26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8
 linux-sunxi#27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c
 crash> bt 0xffff8aeb07544000
 PID: 1110766  TASK: ffff8aeb07544000  CPU: 0    COMMAND: "kworker/u20:9"
  #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45
  jwrdegoede#1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418
  jwrdegoede#2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88
  jwrdegoede#3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b
  jwrdegoede#4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core]
  jwrdegoede#5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core]
  jwrdegoede#6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core]
  linux-sunxi#7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c
  linux-sunxi#8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012
  linux-sunxi#9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d
 linux-sunxi#10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f

After the first encap is attached, flow will be added to encap
entry's flows list. If neigh update is running at this time, the
following encaps of the flow can't hold the encap_tbl_lock and
sleep. If neigh update thread is waiting for that flow's init_done,
deadlock happens.

Fix it by holding lock outside of the for loop. If neigh update is
running, prevent encap flows from offloading. Since the lock is held
outside of the for loop, concurrent creation of encap entries is not
allowed. So remove unnecessary wait_for_completion call for res_ready.

Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Apr 1, 2024
sg_init_one() relies on linearly mapped low memory for the safe
utilization of virt_to_page().  Otherwise, we trigger a kernel BUG,

kernel BUG at include/linux/scatterlist.h:187!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 2997 Comm: syz-executor198 Not tainted 6.8.0-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at sg_set_buf include/linux/scatterlist.h:187 [inline]
PC is at sg_init_one+0x9c/0xa8 lib/scatterlist.c:143
LR is at sg_init_table+0x2c/0x40 lib/scatterlist.c:128
Backtrace:
[<807e16ac>] (sg_init_one) from [<804c1824>] (zswap_decompress+0xbc/0x208 mm/zswap.c:1089)
 r7:83471c80 r6:def6d08c r5:844847d0 r4:ff7e7ef4
[<804c1768>] (zswap_decompress) from [<804c4468>] (zswap_load+0x15c/0x198 mm/zswap.c:1637)
 r9:8446eb80 r8:8446eb80 r7:8446eb84 r6:def6d08c r5:00000001 r4:844847d0
[<804c430c>] (zswap_load) from [<804b9644>] (swap_read_folio+0xa8/0x498 mm/page_io.c:518)
 r9:844ac800 r8:835e6c00 r7:00000000 r6:df955d4c r5:00000001 r4:def6d08c
[<804b959c>] (swap_read_folio) from [<804bb064>] (swap_cluster_readahead+0x1c4/0x34c mm/swap_state.c:684)
 r10:00000000 r9:00000007 r8:df955d4b r7:00000000 r6:00000000 r5:00100cca
 r4:00000001
[<804baea0>] (swap_cluster_readahead) from [<804bb3b8>] (swapin_readahead+0x68/0x4a8 mm/swap_state.c:904)
 r10:df955eb8 r9:00000000 r8:00100cca r7:84476480 r6:00000001 r5:00000000
 r4:00000001
[<804bb350>] (swapin_readahead) from [<8047cde0>] (do_swap_page+0x200/0xcc4 mm/memory.c:4046)
 r10:00000040 r9:00000000 r8:844ac800 r7:84476480 r6:00000001 r5:00000000
 r4:df955eb8
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_pte_fault mm/memory.c:5301 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (__handle_mm_fault mm/memory.c:5439 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_mm_fault+0x3d8/0x12b8 mm/memory.c:5604)
 r10:00000040 r9:842b3900 r8:7eb0d000 r7:84476480 r6:7eb0d000 r5:835e6c00
 r4:00000254
[<8047e2ec>] (handle_mm_fault) from [<80215d28>] (do_page_fault+0x148/0x3a8 arch/arm/mm/fault.c:326)
 r10:00000007 r9:842b3900 r8:7eb0d000 r7:00000207 r6:00000254 r5:7eb0d9b4
 r4:df955fb0
[<80215be0>] (do_page_fault) from [<80216170>] (do_DataAbort+0x38/0xa8 arch/arm/mm/fault.c:558)
 r10:7eb0da7c r9:00000000 r8:80215be0 r7:df955fb0 r6:7eb0d9b4 r5:00000207
 r4:8261d0e0
[<80216138>] (do_DataAbort) from [<80200e3c>] (__dabt_usr+0x5c/0x60 arch/arm/kernel/entry-armv.S:427)
Exception stack(0xdf955fb0 to 0xdf955ff8)
5fa0:                                     00000000 00000000 22d5f800 0008d158
5fc0: 00000000 7eb0d9a4 00000000 00000109 00000000 00000000 7eb0da7c 7eb0da3c
5fe0: 00000000 7eb0d9a0 00000001 00066bd4 00000010 ffffffff
 r8:824a9044 r7:835e6c00 r6:ffffffff r5:00000010 r4:00066bd4
Code: 1a000004 e1822003 e8860094 e89da8f0 (e7f001f2)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	1a000004 	bne	0x18
   4:	e1822003 	orr	r2, r2, r3
   8:	e8860094 	stm	r6, {r2, r4, r7}
   c:	e89da8f0 	ldm	sp, {r4, r5, r6, r7, fp, sp, pc}
* 10:	e7f001f2 	udf	linux-sunxi#18 <-- trapping instruction

Consequently, we have two choices: either employ kmap_to_page() alongside
sg_set_page(), or resort to copying high memory contents to a temporary
buffer residing in low memory.  However, considering the introduction of
the WARN_ON_ONCE in commit ef6e06b ("highmem: fix kmap_to_page() for
kmap_local_page() addresses"), which specifically addresses high memory
concerns, it appears that memcpy remains the sole viable option.

Link: https://lkml.kernel.org/r/20240318234706.95347-1-21cnbao@gmail.com
Fixes: 270700d ("mm/zswap: remove the memcpy if acomp is not sleepable")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reported-by: syzbot+adbc983a1588b7805de3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000bbb3d80613f243a6@google.com/
Tested-by: syzbot+adbc983a1588b7805de3@syzkaller.appspotmail.com
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Apr 30, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 linux-sunxi#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 linux-sunxi#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 linux-sunxi#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 linux-sunxi#10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 linux-sunxi#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 linux-sunxi#12 [ffffa65531497b68] printk at ffffffff89318306
 linux-sunxi#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 linux-sunxi#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 linux-sunxi#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 linux-sunxi#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 linux-sunxi#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 linux-sunxi#18 [ffffa65531497f10] kthread at ffffffff892d2e72
 linux-sunxi#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jun 21, 2024
[ Upstream commit f8bbc07 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 jwrdegoede#1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 jwrdegoede#2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 jwrdegoede#3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 jwrdegoede#4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 jwrdegoede#5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 jwrdegoede#6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 linux-sunxi#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 linux-sunxi#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 linux-sunxi#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 linux-sunxi#10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 linux-sunxi#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 linux-sunxi#12 [ffffa65531497b68] printk at ffffffff89318306
 linux-sunxi#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 linux-sunxi#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 linux-sunxi#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 linux-sunxi#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 linux-sunxi#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 linux-sunxi#18 [ffffa65531497f10] kthread at ffffffff892d2e72
 linux-sunxi#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jul 13, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  linux-sunxi#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  linux-sunxi#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  linux-sunxi#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
linux-sunxi#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
linux-sunxi#11 dio_complete at ffffffff8c2b9fa7
linux-sunxi#12 do_blockdev_direct_IO at ffffffff8c2bc09f
linux-sunxi#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
linux-sunxi#14 generic_file_direct_write at ffffffff8c1dcf14
linux-sunxi#15 __generic_file_write_iter at ffffffff8c1dd07b
linux-sunxi#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
linux-sunxi#17 aio_write at ffffffff8c2cc72e
linux-sunxi#18 kmem_cache_alloc at ffffffff8c248dde
linux-sunxi#19 do_io_submit at ffffffff8c2ccada
linux-sunxi#20 do_syscall_64 at ffffffff8c004984
linux-sunxi#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jul 13, 2024
When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch
platform, the following kernel panic occurs:

  [...]
  Oops[#1]:
  CPU: 22 PID: 2824 Comm: test_progs Tainted: G           OE  6.10.0-rc2+ linux-sunxi#18
  Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018
     ... ...
     ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560
    ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0
   CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
   PRMD: 0000000c (PPLV0 +PIE +PWE)
   EUEN: 00000007 (+FPE +SXE +ASXE -BTE)
   ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
  ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
   BADV: 0000000000000040
   PRID: 0014c011 (Loongson-64bit, Loongson-3C5000)
  Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack
  Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...)
  Stack : ...
  Call Trace:
  [<9000000004162774>] copy_page_to_iter+0x74/0x1c0
  [<90000000048bf6c0>] sk_msg_recvmsg+0x120/0x560
  [<90000000049f2b90>] tcp_bpf_recvmsg_parser+0x170/0x4e0
  [<90000000049aae34>] inet_recvmsg+0x54/0x100
  [<900000000481ad5c>] sock_recvmsg+0x7c/0xe0
  [<900000000481e1a8>] __sys_recvfrom+0x108/0x1c0
  [<900000000481e27c>] sys_recvfrom+0x1c/0x40
  [<9000000004c076ec>] do_syscall+0x8c/0xc0
  [<9000000003731da4>] handle_syscall+0xc4/0x160
  Code: ...
  ---[ end trace 0000000000000000 ]---
  Kernel panic - not syncing: Fatal exception
  Kernel relocated by 0x3510000
   .text @ 0x9000000003710000
   .data @ 0x9000000004d70000
   .bss  @ 0x9000000006469400
  ---[ end Kernel panic - not syncing: Fatal exception ]---
  [...]

This crash happens every time when running sockmap_skb_verdict_shutdown
subtest in sockmap_basic.

This crash is because a NULL pointer is passed to page_address() in the
sk_msg_recvmsg(). Due to the different implementations depending on the
architecture, page_address(NULL) will trigger a panic on Loongarch
platform but not on x86 platform. So this bug was hidden on x86 platform
for a while, but now it is exposed on Loongarch platform. The root cause
is that a zero length skb (skb->len == 0) was put on the queue.

This zero length skb is a TCP FIN packet, which was sent by shutdown(),
invoked in test_sockmap_skb_verdict_shutdown():

	shutdown(p1, SHUT_WR);

In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no
page is put to this sge (see sg_set_page in sg_set_page), but this empty
sge is queued into ingress_msg list.

And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by
sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it
to kmap_local_page() and to page_address(), then kernel panics.

To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(),
if copy is zero, that means it's a zero length skb, skip invoking
copy_page_to_iter(). We are using the EFAULT return triggered by
copy_page_to_iter to check for is_fin in tcp_bpf.c.

Fixes: 604326b ("bpf, sockmap: convert to generic sk_msg interface")
Suggested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/e3a16eacdc6740658ee02a33489b1b9d4912f378.1719992715.git.tanggeliang@kylinos.cn
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 4, 2024
When PG_hwpoison pages are freed they are treated differently in
free_pages_prepare() and instead of being released they are isolated.

Page allocation tag counters are decremented at this point since the page
is considered not in use.  Later on when such pages are released by
unpoison_memory(), the allocation tag counters will be decremented again
and the following warning gets reported:

[  113.930443][ T3282] ------------[ cut here ]------------
[  113.931105][ T3282] alloc_tag was not set
[  113.931576][ T3282] WARNING: CPU: 2 PID: 3282 at ./include/linux/alloc_tag.h:130 pgalloc_tag_sub.part.66+0x154/0x164
[  113.932866][ T3282] Modules linked in: hwpoison_inject fuse ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_man4
[  113.941638][ T3282] CPU: 2 UID: 0 PID: 3282 Comm: madvise11 Kdump: loaded Tainted: G        W          6.11.0-rc4-dirty linux-sunxi#18
[  113.943003][ T3282] Tainted: [W]=WARN
[  113.943453][ T3282] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[  113.944378][ T3282] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  113.945319][ T3282] pc : pgalloc_tag_sub.part.66+0x154/0x164
[  113.946016][ T3282] lr : pgalloc_tag_sub.part.66+0x154/0x164
[  113.946706][ T3282] sp : ffff800087093a10
[  113.947197][ T3282] x29: ffff800087093a10 x28: ffff0000d7a9d400 x27: ffff80008249f0a0
[  113.948165][ T3282] x26: 0000000000000000 x25: ffff80008249f2b0 x24: 0000000000000000
[  113.949134][ T3282] x23: 0000000000000001 x22: 0000000000000001 x21: 0000000000000000
[  113.950597][ T3282] x20: ffff0000c08fcad8 x19: ffff80008251e000 x18: ffffffffffffffff
[  113.952207][ T3282] x17: 0000000000000000 x16: 0000000000000000 x15: ffff800081746210
[  113.953161][ T3282] x14: 0000000000000000 x13: 205d323832335420 x12: 5b5d353031313339
[  113.954120][ T3282] x11: ffff800087093500 x10: 000000000000005d x9 : 00000000ffffffd0
[  113.955078][ T3282] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008236ba90 x6 : c0000000ffff7fff
[  113.956036][ T3282] x5 : ffff000b34bf4dc8 x4 : ffff8000820aba90 x3 : 0000000000000001
[  113.956994][ T3282] x2 : ffff800ab320f000 x1 : 841d1e35ac932e00 x0 : 0000000000000000
[  113.957962][ T3282] Call trace:
[  113.958350][ T3282]  pgalloc_tag_sub.part.66+0x154/0x164
[  113.959000][ T3282]  pgalloc_tag_sub+0x14/0x1c
[  113.959539][ T3282]  free_unref_page+0xf4/0x4b8
[  113.960096][ T3282]  __folio_put+0xd4/0x120
[  113.960614][ T3282]  folio_put+0x24/0x50
[  113.961103][ T3282]  unpoison_memory+0x4f0/0x5b0
[  113.961678][ T3282]  hwpoison_unpoison+0x30/0x48 [hwpoison_inject]
[  113.962436][ T3282]  simple_attr_write_xsigned.isra.34+0xec/0x1cc
[  113.963183][ T3282]  simple_attr_write+0x38/0x48
[  113.963750][ T3282]  debugfs_attr_write+0x54/0x80
[  113.964330][ T3282]  full_proxy_write+0x68/0x98
[  113.964880][ T3282]  vfs_write+0xdc/0x4d0
[  113.965372][ T3282]  ksys_write+0x78/0x100
[  113.965875][ T3282]  __arm64_sys_write+0x24/0x30
[  113.966440][ T3282]  invoke_syscall+0x7c/0x104
[  113.966984][ T3282]  el0_svc_common.constprop.1+0x88/0x104
[  113.967652][ T3282]  do_el0_svc+0x2c/0x38
[  113.968893][ T3282]  el0_svc+0x3c/0x1b8
[  113.969379][ T3282]  el0t_64_sync_handler+0x98/0xbc
[  113.969980][ T3282]  el0t_64_sync+0x19c/0x1a0
[  113.970511][ T3282] ---[ end trace 0000000000000000 ]---

To fix this, clear the page tag reference after the page got isolated
and accounted for.

Link: https://lkml.kernel.org/r/20240825163649.33294-1-hao.ge@linux.dev
Fixes: d224eb0 ("codetag: debug: mark codetags for reserved pages as empty")
Signed-off-by: Hao Ge <gehao@kylinos.cn>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hao Ge <gehao@kylinos.cn>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>	[6.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 6, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    jwrdegoede#1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    jwrdegoede#2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    jwrdegoede#3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    jwrdegoede#4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    jwrdegoede#5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    jwrdegoede#6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    linux-sunxi#7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    linux-sunxi#8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    linux-sunxi#9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    linux-sunxi#10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    linux-sunxi#11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    linux-sunxi#12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    linux-sunxi#13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    linux-sunxi#14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    linux-sunxi#15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    linux-sunxi#16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    linux-sunxi#17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    linux-sunxi#18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    linux-sunxi#19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    linux-sunxi#20 0x55c9400e53ad in main tools/perf/perf.c:561
    linux-sunxi#21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    linux-sunxi#22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    linux-sunxi#23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 6, 2024
commit be346c1 upstream.

The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  jwrdegoede#1 __crash_kexec at ffffffff8c1338fa
  jwrdegoede#2 panic at ffffffff8c1d69b9
  jwrdegoede#3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  jwrdegoede#4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  jwrdegoede#5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  jwrdegoede#6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  linux-sunxi#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  linux-sunxi#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  linux-sunxi#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
linux-sunxi#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
linux-sunxi#11 dio_complete at ffffffff8c2b9fa7
linux-sunxi#12 do_blockdev_direct_IO at ffffffff8c2bc09f
linux-sunxi#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
linux-sunxi#14 generic_file_direct_write at ffffffff8c1dcf14
linux-sunxi#15 __generic_file_write_iter at ffffffff8c1dd07b
linux-sunxi#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
linux-sunxi#17 aio_write at ffffffff8c2cc72e
linux-sunxi#18 kmem_cache_alloc at ffffffff8c248dde
linux-sunxi#19 do_io_submit at ffffffff8c2ccada
linux-sunxi#20 do_syscall_64 at ffffffff8c004984
linux-sunxi#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 6, 2024
[ Upstream commit f0c1802 ]

When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch
platform, the following kernel panic occurs:

  [...]
  Oops[jwrdegoede#1]:
  CPU: 22 PID: 2824 Comm: test_progs Tainted: G           OE  6.10.0-rc2+ linux-sunxi#18
  Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018
     ... ...
     ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560
    ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0
   CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
   PRMD: 0000000c (PPLV0 +PIE +PWE)
   EUEN: 00000007 (+FPE +SXE +ASXE -BTE)
   ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
  ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
   BADV: 0000000000000040
   PRID: 0014c011 (Loongson-64bit, Loongson-3C5000)
  Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack
  Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...)
  Stack : ...
  Call Trace:
  [<9000000004162774>] copy_page_to_iter+0x74/0x1c0
  [<90000000048bf6c0>] sk_msg_recvmsg+0x120/0x560
  [<90000000049f2b90>] tcp_bpf_recvmsg_parser+0x170/0x4e0
  [<90000000049aae34>] inet_recvmsg+0x54/0x100
  [<900000000481ad5c>] sock_recvmsg+0x7c/0xe0
  [<900000000481e1a8>] __sys_recvfrom+0x108/0x1c0
  [<900000000481e27c>] sys_recvfrom+0x1c/0x40
  [<9000000004c076ec>] do_syscall+0x8c/0xc0
  [<9000000003731da4>] handle_syscall+0xc4/0x160
  Code: ...
  ---[ end trace 0000000000000000 ]---
  Kernel panic - not syncing: Fatal exception
  Kernel relocated by 0x3510000
   .text @ 0x9000000003710000
   .data @ 0x9000000004d70000
   .bss  @ 0x9000000006469400
  ---[ end Kernel panic - not syncing: Fatal exception ]---
  [...]

This crash happens every time when running sockmap_skb_verdict_shutdown
subtest in sockmap_basic.

This crash is because a NULL pointer is passed to page_address() in the
sk_msg_recvmsg(). Due to the different implementations depending on the
architecture, page_address(NULL) will trigger a panic on Loongarch
platform but not on x86 platform. So this bug was hidden on x86 platform
for a while, but now it is exposed on Loongarch platform. The root cause
is that a zero length skb (skb->len == 0) was put on the queue.

This zero length skb is a TCP FIN packet, which was sent by shutdown(),
invoked in test_sockmap_skb_verdict_shutdown():

	shutdown(p1, SHUT_WR);

In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no
page is put to this sge (see sg_set_page in sg_set_page), but this empty
sge is queued into ingress_msg list.

And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by
sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it
to kmap_local_page() and to page_address(), then kernel panics.

To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(),
if copy is zero, that means it's a zero length skb, skip invoking
copy_page_to_iter(). We are using the EFAULT return triggered by
copy_page_to_iter to check for is_fin in tcp_bpf.c.

Fixes: 604326b ("bpf, sockmap: convert to generic sk_msg interface")
Suggested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/e3a16eacdc6740658ee02a33489b1b9d4912f378.1719992715.git.tanggeliang@kylinos.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
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