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This patch set introduces two things:

  • Enhance option rgb_quant_range.
  • Add new option ignore_edid

The first one will enable RGB full range automatically when the attached sink claims to support it.
This is done by parsing the 'Video Capability Data Block' from the EDID.

The second adds the ability to enforce the use of the internal fallback video mode list even in case a valid EDID is present. This may help users with some broken TVs, that do not report all modes they really support.

The information from this block is used to detect if a
sink supports overriding of the RGB quantisation range.

Signed-off-by: Rudi <r.ihle@s-t.de>
This new option, which is now the default, will automatically use
full range, when the sink announces that it supports quantisation
overriding. Otherwise, the default range (i.e. limited) is used.

Signed-off-by: Rudi <r.ihle@s-t.de>
Allow the use of the fallback videomode list even in case a valid EDID
is obtainable. This is done by adding 'mxc_hdmi.ignore_edid=1' to the
kernel command line.

Signed-off-by: Rudi <r.ihle@s-t.de>
@warped-rudi warped-rudi force-pushed the solidrun-video-patches1 branch from 5e5b89a to f2c34aa Compare August 17, 2015 13:59
linux4kix added a commit that referenced this pull request Aug 17, 2015
Add / change two command line options for mxc_hdmi
@linux4kix linux4kix merged commit 555cbf4 into SolidRun:3.14-1.0.x-mx6-sr Aug 17, 2015
@warped-rudi warped-rudi deleted the solidrun-video-patches1 branch August 18, 2015 06:00
linux4kix pushed a commit that referenced this pull request Sep 5, 2015
commit ecf5fc6 upstream.

Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  #1 schedule at ffffffff815ab76e
  #2 schedule_timeout at ffffffff815ae5e5
  #3 io_schedule_timeout at ffffffff815aad6a
  #4 bit_wait_io at ffffffff815abfc6
  #5 __wait_on_bit at ffffffff815abda5
  #6 wait_on_page_bit at ffffffff8111fd4f
  #7 shrink_page_list at ffffffff81135445
  #8 shrink_inactive_list at ffffffff81135845
  #9 shrink_lruvec at ffffffff81135ead
 #10 shrink_zone at ffffffff811360c3
 #11 shrink_zones at ffffffff81136eff
 #12 do_try_to_free_pages at ffffffff8113712f
 #13 try_to_free_mem_cgroup_pages at ffffffff811372be
 #14 try_charge at ffffffff81189423
 #15 mem_cgroup_try_charge at ffffffff8118c6f5
 #16 __add_to_page_cache_locked at ffffffff8112137d
 #17 add_to_page_cache_lru at ffffffff81121618
 #18 pagecache_get_page at ffffffff8112170b
 #19 grow_dev_page at ffffffff811c8297
 #20 __getblk_slow at ffffffff811c91d6
 #21 __getblk_gfp at ffffffff811c92c1
 #22 ext4_ext_grow_indepth at ffffffff8124565c
 #23 ext4_ext_create_new_leaf at ffffffff81246ca8
 #24 ext4_ext_insert_extent at ffffffff81246f09
 #25 ext4_ext_map_blocks at ffffffff8124a848
 #26 ext4_map_blocks at ffffffff8121a5b7
 #27 mpage_map_one_extent at ffffffff8121b1fa
 #28 mpage_map_and_submit_extent at ffffffff8121f07b
 #29 ext4_writepages at ffffffff8121f6d5
 #30 do_writepages at ffffffff8112c490
 #31 __filemap_fdatawrite_range at ffffffff81120199
 #32 filemap_flush at ffffffff8112041c
 #33 ext4_alloc_da_blocks at ffffffff81219da1
 #34 ext4_rename at ffffffff81229b91
 #35 ext4_rename2 at ffffffff81229e32
 #36 vfs_rename at ffffffff811a08a5
 #37 SYSC_renameat2 at ffffffff811a3ffc
 #38 sys_renameat2 at ffffffff811a408e
 #39 sys_rename at ffffffff8119e51e
 #40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

[tytso@mit.edu: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 5, 2015
commit f6979ad upstream.

Due to patch "libfc: Do not invoke the response handler after
fc_exch_done()" (commit ID 7030fd6) the lport_recv() call
in fc_exch_recv_req() is passed a dangling pointer. Avoid this
by moving the fc_frame_free() call from fc_invoke_resp() to its
callers. This patch fixes the following crash:

general protection fault: 0000 [#3] PREEMPT SMP
RIP: fc_lport_recv_req+0x72/0x280 [libfc]
Call Trace:
 fc_exch_recv+0x642/0xde0 [libfc]
 fcoe_percpu_receive_thread+0x46a/0x5ed [fcoe]
 kthread+0x10a/0x120
 ret_from_fork+0x42/0x70

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Oct 9, 2015
commit ecf5fc6 upstream.

Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  SolidRun#1 schedule at ffffffff815ab76e
  SolidRun#2 schedule_timeout at ffffffff815ae5e5
  SolidRun#3 io_schedule_timeout at ffffffff815aad6a
  SolidRun#4 bit_wait_io at ffffffff815abfc6
  SolidRun#5 __wait_on_bit at ffffffff815abda5
  SolidRun#6 wait_on_page_bit at ffffffff8111fd4f
  SolidRun#7 shrink_page_list at ffffffff81135445
  SolidRun#8 shrink_inactive_list at ffffffff81135845
  SolidRun#9 shrink_lruvec at ffffffff81135ead
 SolidRun#10 shrink_zone at ffffffff811360c3
 SolidRun#11 shrink_zones at ffffffff81136eff
 SolidRun#12 do_try_to_free_pages at ffffffff8113712f
 SolidRun#13 try_to_free_mem_cgroup_pages at ffffffff811372be
 SolidRun#14 try_charge at ffffffff81189423
 SolidRun#15 mem_cgroup_try_charge at ffffffff8118c6f5
 SolidRun#16 __add_to_page_cache_locked at ffffffff8112137d
 SolidRun#17 add_to_page_cache_lru at ffffffff81121618
 SolidRun#18 pagecache_get_page at ffffffff8112170b
 SolidRun#19 grow_dev_page at ffffffff811c8297
 SolidRun#20 __getblk_slow at ffffffff811c91d6
 SolidRun#21 __getblk_gfp at ffffffff811c92c1
 SolidRun#22 ext4_ext_grow_indepth at ffffffff8124565c
 SolidRun#23 ext4_ext_create_new_leaf at ffffffff81246ca8
 SolidRun#24 ext4_ext_insert_extent at ffffffff81246f09
 SolidRun#25 ext4_ext_map_blocks at ffffffff8124a848
 SolidRun#26 ext4_map_blocks at ffffffff8121a5b7
 SolidRun#27 mpage_map_one_extent at ffffffff8121b1fa
 SolidRun#28 mpage_map_and_submit_extent at ffffffff8121f07b
 SolidRun#29 ext4_writepages at ffffffff8121f6d5
 SolidRun#30 do_writepages at ffffffff8112c490
 SolidRun#31 __filemap_fdatawrite_range at ffffffff81120199
 SolidRun#32 filemap_flush at ffffffff8112041c
 SolidRun#33 ext4_alloc_da_blocks at ffffffff81219da1
 SolidRun#34 ext4_rename at ffffffff81229b91
 SolidRun#35 ext4_rename2 at ffffffff81229e32
 SolidRun#36 vfs_rename at ffffffff811a08a5
 SolidRun#37 SYSC_renameat2 at ffffffff811a3ffc
 SolidRun#38 sys_renameat2 at ffffffff811a408e
 SolidRun#39 sys_rename at ffffffff8119e51e
 SolidRun#40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

Cc: stable@vger.kernel.org # 3.9+
[tytso@mit.edu: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Oct 9, 2015
commit fc5fee8 upstream.

It turns out that a PV domU also requires the "Xen PV" APIC
driver. Otherwise, the flat driver is used and we get stuck in busy
loops that never exit, such as in this stack trace:

(gdb) target remote localhost:9999
Remote debugging using localhost:9999
__xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
56              while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
(gdb) bt
 #0  __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
 SolidRun#1  __default_send_IPI_shortcut (shortcut=<optimized out>,
dest=<optimized out>, vector=<optimized out>) at
./arch/x86/include/asm/ipi.h:75
 SolidRun#2  apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54
 SolidRun#3  0xffffffff81011336 in arch_irq_work_raise () at
arch/x86/kernel/irq_work.c:47
 SolidRun#4  0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at
kernel/irq_work.c:100
 SolidRun#5  0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633
 SolidRun#6  0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized
out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>,
fmt=<optimized out>, args=<optimized out>)
    at kernel/printk/printk.c:1778
 SolidRun#7  0xffffffff816010c8 in printk (fmt=<optimized out>) at
kernel/printk/printk.c:1868
 SolidRun#8  0xffffffffc00013ea in ?? ()
 SolidRun#9  0x0000000000000000 in ?? ()

Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Oct 9, 2015
commit f6979ad upstream.

Due to patch "libfc: Do not invoke the response handler after
fc_exch_done()" (commit ID 7030fd6) the lport_recv() call
in fc_exch_recv_req() is passed a dangling pointer. Avoid this
by moving the fc_frame_free() call from fc_invoke_resp() to its
callers. This patch fixes the following crash:

general protection fault: 0000 [SolidRun#3] PREEMPT SMP
RIP: fc_lport_recv_req+0x72/0x280 [libfc]
Call Trace:
 fc_exch_recv+0x642/0xde0 [libfc]
 fcoe_percpu_receive_thread+0x46a/0x5ed [fcoe]
 kthread+0x10a/0x120
 ret_from_fork+0x42/0x70

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Oct 9, 2015
commit 49bda21 upstream.

This commit fixes the following issues:

1. The 9th bit of buf was believed to be the LSB of divisor's
exponent, but the hardware interprets it as MSB (9th bit) of the
mantissa. The exponent is actually one bit shorter and applies
to base 4, not 2 as previously believed.

2. Loop iterations doubled the exponent instead of incrementing.

3. The exponent wasn't checked for overflow.

4. The function returned requested rate instead of actual rate.

Due to issue SolidRun#2, the old code deviated from the wrong formula
described in SolidRun#1 and actually yielded correct rates when divisor
was lower than 4096 by using exponents of 0, 2 or 4 base-2,
interpreted as 0, 1, 2 base-4 with the 9th mantissa bit clear.
However, at 93.75 kbaud or less the rate turned out too slow
due to SolidRun#2 or too fast due to SolidRun#2 and SolidRun#3.

I tested this patch by sending and validating 0x00,0x01,..,0xff
to an FTDI dongle at 234, 987, 2401, 9601, 31415, 115199, 250k,
500k, 750k, 1M, 1.5M, 3M+1 baud. All rates passed.

I also used pv to check speed at some rates unsupported by FTDI:
45 (the lowest possible), 2M, 4M, 5M and 6M-1. Looked sane.

Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
Fixes: 399aa9a ("USB: pl2303: use divisors for unsupported baud
rates")
[johan: update summary ]
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Nov 3, 2015
commit eddd382 upstream.

Dmitry Vyukov reported the following using trinity and the memory
error detector AddressSanitizer
(https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel).

[ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on
address ffff88002e280000
[ 124.576801] ffff88002e280000 is located 131938492886538 bytes to
the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a)
[ 124.578633] Accessed by thread T10915:
[ 124.579295] inlined in describe_heap_address
./arch/x86/mm/asan/report.c:164
[ 124.579295] #0 ffffffff810dd277 in asan_report_error
./arch/x86/mm/asan/report.c:278
[ 124.580137] SolidRun#1 ffffffff810dc6a0 in asan_check_region
./arch/x86/mm/asan/asan.c:37
[ 124.581050] SolidRun#2 ffffffff810dd423 in __tsan_read8 ??:0
[ 124.581893] SolidRun#3 ffffffff8107c093 in get_wchan
./arch/x86/kernel/process_64.c:444

The address checks in the 64bit implementation of get_wchan() are
wrong in several ways:

 - The lower bound of the stack is not the start of the stack
   page. It's the start of the stack page plus sizeof (struct
   thread_info)

 - The upper bound must be:

       top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long).

   The 2 * sizeof(unsigned long) is required because the stack pointer
   points at the frame pointer. The layout on the stack is: ... IP FP
   ... IP FP. So we need to make sure that both IP and FP are in the
   bounds.

Fix the bound checks and get rid of the mix of numeric constants, u64
and unsigned long. Making all unsigned long allows us to use the same
function for 32bit as well.

Use READ_ONCE() when accessing the stack. This does not prevent a
concurrent wakeup of the task and the stack changing, but at least it
avoids TOCTOU.

Also check task state at the end of the loop. Again that does not
prevent concurrent changes, but it avoids walking for nothing.

Add proper comments while at it.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Based-on-patch-from: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Link: http://lkml.kernel.org/r/20150930083302.694788319@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Nov 3, 2015
commit e81107d upstream.

My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 SolidRun#1 [ffff88303d107bd0] schedule at ffffffff815c513e
 SolidRun#2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 SolidRun#3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 SolidRun#4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 SolidRun#5 [ffff88303d107dd0] tty_read at ffffffff81368013
 SolidRun#6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 SolidRun#7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 SolidRun#8 [ffff88303d107f00] sys_read at ffffffff811a4306
 SolidRun#9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Jan 10, 2016
When a43eec3 ("bpf: introduce bpf_perf_event_output() helper") added
PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw
array that wasn't initialized, thus set to NULL, fix print_symbol_events()
to check for that case so that we don't crash if this happens again.

  (gdb) bt
  #0  __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198
  SolidRun#1  strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252
  SolidRun#2  0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall")
      at util/parse-events.c:1615
  SolidRun#3  print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675
  SolidRun#4  0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68
  SolidRun#5  0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370
  SolidRun#6  0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429
  SolidRun#7  run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473
  SolidRun#8  main (argc=2, argv=0x7fffffffe390) at perf.c:588
  (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT]
  $4 = {symbol = 0x0, alias = 0x0}
  (gdb)

A patch to robustify perf to not segfault when the next counter gets added in
the kernel will follow this one.

Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
linux4kix pushed a commit that referenced this pull request Jan 26, 2016
As per changes in include/linux/jbd_common.h for avoiding the
bit_spin_locks on RT ("fs: jbd/jbd2: Make state lock and journal
head lock rt safe") we do the same thing here.

We use the non atomic __set_bit and __clear_bit inside the scope of
the lock to preserve the ability of the existing LIST_DEBUG code to
use the zero'th bit in the sanity checks.

As a bit spinlock, we had no lockdep visibility into the usage
of the list head locking.  Now, if we were to implement it as a
standard non-raw spinlock, we would see:

BUG: sleeping function called from invalid context at kernel/rtmutex.c:658
in_atomic(): 1, irqs_disabled(): 0, pid: 122, name: udevd
5 locks held by udevd/122:
 #0:  (&sb->s_type->i_mutex_key#7/1){+.+.+.}, at: [<ffffffff811967e8>] lock_rename+0xe8/0xf0
 #1:  (rename_lock){+.+...}, at: [<ffffffff811a277c>] d_move+0x2c/0x60
 #2:  (&dentry->d_lock){+.+...}, at: [<ffffffff811a0763>] dentry_lock_for_move+0xf3/0x130
 #3:  (&dentry->d_lock/2){+.+...}, at: [<ffffffff811a0734>] dentry_lock_for_move+0xc4/0x130
 #4:  (&dentry->d_lock/3){+.+...}, at: [<ffffffff811a0747>] dentry_lock_for_move+0xd7/0x130
Pid: 122, comm: udevd Not tainted 3.4.47-rt62 #7
Call Trace:
 [<ffffffff810b9624>] __might_sleep+0x134/0x1f0
 [<ffffffff817a24d4>] rt_spin_lock+0x24/0x60
 [<ffffffff811a0c4c>] __d_shrink+0x5c/0xa0
 [<ffffffff811a1b2d>] __d_drop+0x1d/0x40
 [<ffffffff811a24be>] __d_move+0x8e/0x320
 [<ffffffff811a278e>] d_move+0x3e/0x60
 [<ffffffff81199598>] vfs_rename+0x198/0x4c0
 [<ffffffff8119b093>] sys_renameat+0x213/0x240
 [<ffffffff817a2de5>] ? _raw_spin_unlock+0x35/0x60
 [<ffffffff8107781c>] ? do_page_fault+0x1ec/0x4b0
 [<ffffffff817a32ca>] ? retint_swapgs+0xe/0x13
 [<ffffffff813eb0e6>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff8119b0db>] sys_rename+0x1b/0x20
 [<ffffffff817a3b96>] system_call_fastpath+0x1a/0x1f

Since we are only taking the lock during short lived list operations,
lets assume for now that it being raw won't be a significant latency
concern.

Cc: stable-rt@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
linux4kix pushed a commit that referenced this pull request Jan 26, 2016
do_set_cpus_allowed() is not safe vs ->sched_class change.

crash> bt
PID: 11676  TASK: ffff88026f979da0  CPU: 22  COMMAND: "sync_unplug/22"
 #0 [ffff880274d25bc8] machine_kexec at ffffffff8103b41c
 #1 [ffff880274d25c18] crash_kexec at ffffffff810d881a
 #2 [ffff880274d25cd8] oops_end at ffffffff81525818
 #3 [ffff880274d25cf8] do_invalid_op at ffffffff81003096
 #4 [ffff880274d25d90] invalid_op at ffffffff8152d3de
    [exception RIP: set_cpus_allowed_rt+18]
    RIP: ffffffff8109e012  RSP: ffff880274d25e48  RFLAGS: 00010202
    RAX: ffffffff8109e000  RBX: ffff88026f979da0  RCX: ffff8802770cb6e8
    RDX: 0000000000000000  RSI: ffffffff81add700  RDI: ffff88026f979da0
    RBP: ffff880274d25e78   R8: ffffffff816112e0   R9: 0000000000000001
    R10: 0000000000000001  R11: 0000000000011940  R12: ffff88026f979da0
    R13: ffff8802770cb6d0  R14: ffff880274d25fd8  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffff880274d25e60] do_set_cpus_allowed at ffffffff8108e65f
 #6 [ffff880274d25e80] sync_unplug_thread at ffffffff81058c08
 #7 [ffff880274d25ed8] kthread at ffffffff8107cad6
 #8 [ffff880274d25f50] ret_from_fork at ffffffff8152bbbc
crash> task_struct ffff88026f979da0 | grep class
  sched_class = 0xffffffff816111e0 <fair_sched_class+64>,

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Feb 22, 2016
commit 3d5fe03 upstream.

We can end up allocating a new compression stream with GFP_KERNEL from
within the IO path, which may result is nested (recursive) IO
operations.  That can introduce problems if the IO path in question is a
reclaimer, holding some locks that will deadlock nested IOs.

Allocate streams and working memory using GFP_NOIO flag, forbidding
recursive IO and FS operations.

An example:

  inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
  git/20158 [HC0[0]:SC0[0]:HE1:SE1] takes:
   (jbd2_handle){+.+.?.}, at:  start_this_handle+0x4ca/0x555
  {IN-RECLAIM_FS-W} state was registered at:
     __lock_acquire+0x8da/0x117b
     lock_acquire+0x10c/0x1a7
     start_this_handle+0x52d/0x555
     jbd2__journal_start+0xb4/0x237
     __ext4_journal_start_sb+0x108/0x17e
     ext4_dirty_inode+0x32/0x61
     __mark_inode_dirty+0x16b/0x60c
     iput+0x11e/0x274
     __dentry_kill+0x148/0x1b8
     shrink_dentry_list+0x274/0x44a
     prune_dcache_sb+0x4a/0x55
     super_cache_scan+0xfc/0x176
     shrink_slab.part.14.constprop.25+0x2a2/0x4d3
     shrink_zone+0x74/0x140
     kswapd+0x6b7/0x930
     kthread+0x107/0x10f
     ret_from_fork+0x3f/0x70
  irq event stamp: 138297
  hardirqs last  enabled at (138297):  debug_check_no_locks_freed+0x113/0x12f
  hardirqs last disabled at (138296):  debug_check_no_locks_freed+0x33/0x12f
  softirqs last  enabled at (137818):  __do_softirq+0x2d3/0x3e9
  softirqs last disabled at (137813):  irq_exit+0x41/0x95

               other info that might help us debug this:
   Possible unsafe locking scenario:
         CPU0
         ----
    lock(jbd2_handle);
    <Interrupt>
      lock(jbd2_handle);

                *** DEADLOCK ***
  5 locks held by git/20158:
   #0:  (sb_writers#7){.+.+.+}, at: [<ffffffff81155411>] mnt_want_write+0x24/0x4b
   SolidRun#1:  (&type->i_mutex_dir_key#2/1){+.+.+.}, at: [<ffffffff81145087>] lock_rename+0xd9/0xe3
   SolidRun#2:  (&sb->s_type->i_mutex_key#11){+.+.+.}, at: [<ffffffff8114f8e2>] lock_two_nondirectories+0x3f/0x6b
   SolidRun#3:  (&sb->s_type->i_mutex_key#11/4){+.+.+.}, at: [<ffffffff8114f909>] lock_two_nondirectories+0x66/0x6b
   SolidRun#4:  (jbd2_handle){+.+.?.}, at: [<ffffffff811e31db>] start_this_handle+0x4ca/0x555

               stack backtrace:
  CPU: 2 PID: 20158 Comm: git Not tainted 4.1.0-rc7-next-20150615-dbg-00016-g8bdf555-dirty Freescale#211
  Call Trace:
    dump_stack+0x4c/0x6e
    mark_lock+0x384/0x56d
    mark_held_locks+0x5f/0x76
    lockdep_trace_alloc+0xb2/0xb5
    kmem_cache_alloc_trace+0x32/0x1e2
    zcomp_strm_alloc+0x25/0x73 [zram]
    zcomp_strm_multi_find+0xe7/0x173 [zram]
    zcomp_strm_find+0xc/0xe [zram]
    zram_bvec_rw+0x2ca/0x7e0 [zram]
    zram_make_request+0x1fa/0x301 [zram]
    generic_make_request+0x9c/0xdb
    submit_bio+0xf7/0x120
    ext4_io_submit+0x2e/0x43
    ext4_bio_write_page+0x1b7/0x300
    mpage_submit_page+0x60/0x77
    mpage_map_and_submit_buffers+0x10f/0x21d
    ext4_writepages+0xc8c/0xe1b
    do_writepages+0x23/0x2c
    __filemap_fdatawrite_range+0x84/0x8b
    filemap_flush+0x1c/0x1e
    ext4_alloc_da_blocks+0xb8/0x117
    ext4_rename+0x132/0x6dc
    ? mark_held_locks+0x5f/0x76
    ext4_rename2+0x29/0x2b
    vfs_rename+0x540/0x636
    SyS_renameat2+0x359/0x44d
    SyS_rename+0x1e/0x20
    entry_SYSCALL_64_fastpath+0x12/0x6f

[minchan@kernel.org: add stable mark]
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Kyeongdon Kim <kyeongdon.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Mar 2, 2016
commit ec183d2 upstream.

Fixes segmentation fault using, for instance:

  (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".

 Program received signal SIGSEGV, Segmentation fault.
  0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  (gdb) bt
  #0  0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  SolidRun#1  0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:433
  SolidRun#2  0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:498
  SolidRun#3  0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:936
  SolidRun#4  0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391
  SolidRun#5  0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361
  SolidRun#6  0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401
  SolidRun#7  0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253
  SolidRun#8  0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364
  SolidRun#9  0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664
  SolidRun#10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539
  SolidRun#11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264
  SolidRun#12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390
  SolidRun#13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451
  SolidRun#14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495
  SolidRun#15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618
(gdb)

Intel PT attempts to find the sched:sched_switch tracepoint but that seg
faults if tracefs is not readable, because the error reporting structure
is null, as errors are not reported when automatically adding
tracepoints.  Fix by checking before using.

Committer note:

This doesn't take place in a kernel that supports
perf_event_attr.context_switch, that is the default way that will be
used for tracking context switches, only in older kernels, like 4.2, in
a machine with Intel PT (e.g. Broadwell) for non-priviledged users.

Further info from a similar patch by Wang:

The error is in tracepoint_error: it assumes the 'e' parameter is valid.

However, there are many situation a parse_event() can be called without
parse_events_error. See result of

  $ grep 'parse_events(.*NULL)' ./tools/perf/ -r'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tong Zhang <ztong@vt.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output")
Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Mar 2, 2016
commit 361cad3 upstream.

We've seen this in a packet capture - I've intermixed what I
think was going on. The fix here is to grab the so_lock sooner.

1964379 -> SolidRun#1 open (for write) reply seqid=1
1964393 -> SolidRun#2 open (for read) reply seqid=2

  __nfs4_close(), state->n_wronly--
  nfs4_state_set_mode_locked(), changes state->state = [R]
  state->flags is [RW]
  state->state is [R], state->n_wronly == 0, state->n_rdonly == 1

1964398 -> SolidRun#3 open (for write) call -> because close is already running
1964399 -> downgrade (to read) call seqid=2 (close of SolidRun#1)
1964402 -> SolidRun#3 open (for write) reply seqid=3

 __update_open_stateid()
   nfs_set_open_stateid_locked(), changes state->flags
   state->flags is [RW]
   state->state is [R], state->n_wronly == 0, state->n_rdonly == 1
   new sequence number is exposed now via nfs4_stateid_copy()

   next step would be update_open_stateflags(), pending so_lock

1964403 -> downgrade reply seqid=2, fails with OLD_STATEID (close of SolidRun#1)

   nfs4_close_prepare() gets so_lock and recalcs flags -> send close

1964405 -> downgrade (to read) call seqid=3 (close of SolidRun#1 retry)

   __update_open_stateid() gets so_lock
 * update_open_stateflags() updates state->n_wronly.
   nfs4_state_set_mode_locked() updates state->state

   state->flags is [RW]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

 * should have suppressed the preceding nfs4_close_prepare() from
   sending open_downgrade

1964406 -> write call
1964408 -> downgrade (to read) reply seqid=4 (close of SolidRun#1 retry)

   nfs_clear_open_stateid_locked()
   state->flags is [R]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

1964409 -> write reply (fails, openmode)

Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Mar 18, 2016
[ Upstream commit 7716682 ]

Ilya reported following lockdep splat:

kernel: =========================
kernel: [ BUG: held lock freed! ]
kernel: 4.5.0-rc1-ceph-00026-g5e0a311 SolidRun#1 Not tainted
kernel: -------------------------
kernel: swapper/5/0 is freeing memory
ffff880035c9d200-ffff880035c9dbff, with a lock still held there!
kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0
kernel: 4 locks held by swapper/5/0:
kernel: #0:  (rcu_read_lock){......}, at: [<ffffffff8169ef6b>]
netif_receive_skb_internal+0x4b/0x1f0
kernel: SolidRun#1:  (rcu_read_lock){......}, at: [<ffffffff816e977f>]
ip_local_deliver_finish+0x3f/0x380
kernel: SolidRun#2:  (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>]
sk_clone_lock+0x19b/0x440
kernel: SolidRun#3:  (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0

To properly fix this issue, inet_csk_reqsk_queue_add() needs
to return to its callers if the child as been queued
into accept queue.

We also need to make sure listener is still there before
calling sk->sk_data_ready(), by holding a reference on it,
since the reference carried by the child can disappear as
soon as the child is put on accept queue.

Reported-by: Ilya Dryomov <idryomov@gmail.com>
Fixes: ebb516a ("tcp/dccp: fix race at listener dismantle phase")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Mar 18, 2016
commit 09dc9cd upstream.

The code produces the following trace:

[1750924.419007] general protection fault: 0000 [SolidRun#3] SMP
[1750924.420364] Modules linked in: nfnetlink autofs4 rpcsec_gss_krb5 nfsv4
dcdbas rfcomm bnep bluetooth nfsd auth_rpcgss nfs_acl dm_multipath nfs lockd
scsi_dh sunrpc fscache radeon ttm drm_kms_helper drm serio_raw parport_pc
ppdev i2c_algo_bit lpc_ich ipmi_si ib_mthca ib_qib dca lp parport ib_ipoib
mac_hid ib_cm i3000_edac ib_sa ib_uverbs edac_core ib_umad ib_mad ib_core
ib_addr tg3 ptp dm_mirror dm_region_hash dm_log psmouse pps_core
[1750924.420364] CPU: 1 PID: 8401 Comm: python Tainted: G D
3.13.0-39-generic SolidRun#66-Ubuntu
[1750924.420364] Hardware name: Dell Computer Corporation PowerEdge
860/0XM089, BIOS A04 07/24/2007
[1750924.420364] task: ffff8800366a9800 ti: ffff88007af1c000 task.ti:
ffff88007af1c000
[1750924.420364] RIP: 0010:[<ffffffffa0131d51>] [<ffffffffa0131d51>]
qib_mcast_qp_free+0x11/0x50 [ib_qib]
[1750924.420364] RSP: 0018:ffff88007af1dd70  EFLAGS: 00010246
[1750924.420364] RAX: 0000000000000001 RBX: ffff88007b822688 RCX:
000000000000000f
[1750924.420364] RDX: ffff88007b822688 RSI: ffff8800366c15a0 RDI:
6764697200000000
[1750924.420364] RBP: ffff88007af1dd78 R08: 0000000000000001 R09:
0000000000000000
[1750924.420364] R10: 0000000000000011 R11: 0000000000000246 R12:
ffff88007baa1d98
[1750924.420364] R13: ffff88003ecab000 R14: ffff88007b822660 R15:
0000000000000000
[1750924.420364] FS:  00007ffff7fd8740(0000) GS:ffff88007fc80000(0000)
knlGS:0000000000000000
[1750924.420364] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1750924.420364] CR2: 00007ffff597c750 CR3: 000000006860b000 CR4:
00000000000007e0
[1750924.420364] Stack:
[1750924.420364]  ffff88007b822688 ffff88007af1ddf0 ffffffffa0132429
000000007af1de20
[1750924.420364]  ffff88007baa1dc8 ffff88007baa0000 ffff88007af1de70
ffffffffa00cb313
[1750924.420364]  00007fffffffde88 0000000000000000 0000000000000008
ffff88003ecab000
[1750924.420364] Call Trace:
[1750924.420364]  [<ffffffffa0132429>] qib_multicast_detach+0x1e9/0x350
[ib_qib]
[1750924.568035]  [<ffffffffa00cb313>] ? ib_uverbs_modify_qp+0x323/0x3d0
[ib_uverbs]
[1750924.568035]  [<ffffffffa0092d61>] ib_detach_mcast+0x31/0x50 [ib_core]
[1750924.568035]  [<ffffffffa00cc213>] ib_uverbs_detach_mcast+0x93/0x170
[ib_uverbs]
[1750924.568035]  [<ffffffffa00c61f6>] ib_uverbs_write+0xc6/0x2c0 [ib_uverbs]
[1750924.568035]  [<ffffffff81312e68>] ? apparmor_file_permission+0x18/0x20
[1750924.568035]  [<ffffffff812d4cd3>] ? security_file_permission+0x23/0xa0
[1750924.568035]  [<ffffffff811bd214>] vfs_write+0xb4/0x1f0
[1750924.568035]  [<ffffffff811bdc49>] SyS_write+0x49/0xa0
[1750924.568035]  [<ffffffff8172f7ed>] system_call_fastpath+0x1a/0x1f
[1750924.568035] Code: 66 2e 0f 1f 84 00 00 00 00 00 31 c0 5d c3 66 2e 0f 1f
84 00 00 00 00 00 66 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 10
<f0> ff 8f 40 01 00 00 74 0e 48 89 df e8 8e f8 06 e1 5b 5d c3 0f
[1750924.568035] RIP  [<ffffffffa0131d51>] qib_mcast_qp_free+0x11/0x50
[ib_qib]
[1750924.568035]  RSP <ffff88007af1dd70>
[1750924.650439] ---[ end trace 73d5d4b3f8ad4851 ]

The fix is to note the qib_mcast_qp that was found.   If none is found, then
return EINVAL indicating the error.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Mar 18, 2016
commit d144dfe upstream.

If we use USB ID pin as wakeup source, and there is a USB block
device on this USB OTG (ID) cable, the system will be deadlock
after system resume.

The root cause for this problem is: the workqueue ci_otg may try
to remove hcd before the driver resume has finished, and hcd will
disconnect the device on it, then, it will call device_release_driver,
and holds the device lock "dev->mutex", but it is never unlocked since
it waits workqueue writeback to run to flush the block information, but
the workqueue writeback is freezable, it is not thawed before driver
resume has finished.

When the driver (device: sd 0:0:0:0:) resume goes to dpm_complete, it
tries to get its device lock "dev->mutex", but it can't get it forever,
then the deadlock occurs. Below call stacks show the situation.

So, in order to fix this problem, we need to change workqueue ci_otg
as freezable, then the work item in this workqueue will be run after
driver's resume, this workqueue will not be blocked forever like above
case since the workqueue writeback has been thawed too.

Tested at: i.mx6qdl-sabresd and i.mx6sx-sdb.

[  555.178869] kworker/u2:13   D c07de74c     0   826      2 0x00000000
[  555.185310] Workqueue: ci_otg ci_otg_work
[  555.189353] Backtrace:
[  555.191849] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  555.198912]  r10:ee471ba0 r9:00000000 r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4
[  555.206867]  r4:ee470000
[  555.209453] [<c07dec24>] (schedule) from [<c07e2fc4>] (schedule_timeout+0x15c/0x1e0)
[  555.217212]  r4:7fffffff r3:edc2b000
[  555.220862] [<c07e2e68>] (schedule_timeout) from [<c07df6c8>] (wait_for_common+0x94/0x144)
[  555.229140]  r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 r4:7fffffff
[  555.235980] [<c07df634>] (wait_for_common) from [<c07df790>] (wait_for_completion+0x18/0x1c)
[  555.244430]  r10:00000001 r9:c0b5563c r8:c0042e48 r7:ef086000 r6:eea4372c r5:ef131b00
[  555.252383]  r4:00000000
[  555.254970] [<c07df778>] (wait_for_completion) from [<c0043cb8>] (flush_work+0x19c/0x234)
[  555.263177] [<c0043b1c>] (flush_work) from [<c0043fac>] (flush_delayed_work+0x48/0x4c)
[  555.271106]  r8:ed5b5000 r7:c0b38a3c r6:eea439cc r5:eea4372c r4:eea4372c
[  555.277958] [<c0043f64>] (flush_delayed_work) from [<c00eae18>] (bdi_unregister+0x84/0xec)
[  555.286236]  r4:eea43520 r3:20000153
[  555.289885] [<c00ead94>] (bdi_unregister) from [<c02c2154>] (blk_cleanup_queue+0x180/0x29c)
[  555.298250]  r5:eea43808 r4:eea43400
[  555.301909] [<c02c1fd4>] (blk_cleanup_queue) from [<c0417914>] (__scsi_remove_device+0x48/0xb8)
[  555.310623]  r7:00000000 r6:20000153 r5:ededa950 r4:ededa800
[  555.316403] [<c04178cc>] (__scsi_remove_device) from [<c0415e90>] (scsi_forget_host+0x64/0x68)
[  555.325028]  r5:ededa800 r4:ed5b5000
[  555.328689] [<c0415e2c>] (scsi_forget_host) from [<c0409828>] (scsi_remove_host+0x78/0x104)
[  555.337054]  r5:ed5b5068 r4:ed5b5000
[  555.340709] [<c04097b0>] (scsi_remove_host) from [<c04cdfcc>] (usb_stor_disconnect+0x50/0xb4)
[  555.349247]  r6:ed5b56e4 r5:ed5b5818 r4:ed5b5690 r3:00000008
[  555.355025] [<c04cdf7c>] (usb_stor_disconnect) from [<c04b3bc8>] (usb_unbind_interface+0x78/0x25c)
[  555.363997]  r8:c13919b4 r7:edd3c000 r6:edd3c020 r5:ee551c68 r4:ee551c00 r3:c04cdf7c
[  555.371892] [<c04b3b50>] (usb_unbind_interface) from [<c03dc248>] (__device_release_driver+0x8c/0x118)
[  555.381213]  r10:00000001 r9:edd90c00 r8:c13919b4 r7:ee551c68 r6:c0b546e0 r5:c0b5563c
[  555.389167]  r4:edd3c020
[  555.391752] [<c03dc1bc>] (__device_release_driver) from [<c03dc2fc>] (device_release_driver+0x28/0x34)
[  555.401071]  r5:edd3c020 r4:edd3c054
[  555.404721] [<c03dc2d4>] (device_release_driver) from [<c03db304>] (bus_remove_device+0xe0/0x110)
[  555.413607]  r5:edd3c020 r4:ef17f04c
[  555.417253] [<c03db224>] (bus_remove_device) from [<c03d8128>] (device_del+0x114/0x21c)
[  555.425270]  r6:edd3c028 r5:edd3c020 r4:ee551c00 r3:00000000
[  555.431045] [<c03d8014>] (device_del) from [<c04b1560>] (usb_disable_device+0xa4/0x1e8)
[  555.439061]  r8:edd3c000 r7:eded8000 r6:00000000 r5:00000001 r4:ee551c00
[  555.445906] [<c04b14bc>] (usb_disable_device) from [<c04a8e54>] (usb_disconnect+0x74/0x224)
[  555.454271]  r9:edd90c00 r8:ee551000 r7:ee551c68 r6:ee551c9c r5:ee551c00 r4:00000001
[  555.462156] [<c04a8de0>] (usb_disconnect) from [<c04a8fb8>] (usb_disconnect+0x1d8/0x224)
[  555.470259]  r10:00000001 r9:edd90000 r8:ee471e2c r7:ee551468 r6:ee55149c r5:ee551400
[  555.478213]  r4:00000001
[  555.480797] [<c04a8de0>] (usb_disconnect) from [<c04ae5ec>] (usb_remove_hcd+0xa0/0x1ac)
[  555.488813]  r10:00000001 r9:ee471eb0 r8:00000000 r7:ef3d9500 r6:eded810c r5:eded80b0
[  555.496765]  r4:eded8000
[  555.499351] [<c04ae54c>] (usb_remove_hcd) from [<c04d4158>] (host_stop+0x28/0x64)
[  555.506847]  r6:eeb50010 r5:eded8000 r4:eeb51010
[  555.511563] [<c04d4130>] (host_stop) from [<c04d09b8>] (ci_otg_work+0xc4/0x124)
[  555.518885]  r6:00000001 r5:eeb50010 r4:eeb502a0 r3:c04d4130
[  555.524665] [<c04d08f4>] (ci_otg_work) from [<c00454f0>] (process_one_work+0x194/0x420)
[  555.532682]  r6:ef086000 r5:eeb502a0 r4:edc44480
[  555.537393] [<c004535c>] (process_one_work) from [<c00457b0>] (worker_thread+0x34/0x514)
[  555.545496]  r10:edc44480 r9:ef086000 r8:c0b1a100 r7:ef086034 r6:00000088 r5:edc44498
[  555.553450]  r4:ef086000
[  555.556032] [<c004577c>] (worker_thread) from [<c004bab4>] (kthread+0xdc/0xf8)
[  555.563268]  r10:00000000 r9:00000000 r8:00000000 r7:c004577c r6:edc44480 r5:eddc15c0
[  555.571221]  r4:00000000
[  555.573804] [<c004b9d8>] (kthread) from [<c000fef0>] (ret_from_fork+0x14/0x24)
[  555.581040]  r7:00000000 r6:00000000 r5:c004b9d8 r4:eddc15c0

[  553.429383] sh              D c07de74c     0   694    691 0x00000000
[  553.435801] Backtrace:
[  553.438295] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  553.445358]  r10:edd3c054 r9:edd3c078 r8:edddbd50 r7:edcbbc00 r6:c1377c34 r5:60000153
[  553.453313]  r4:eddda000
[  553.455896] [<c07dec24>] (schedule) from [<c07deff8>] (schedule_preempt_disabled+0x10/0x14)
[  553.464261]  r4:edd3c058 r3:0000000a
[  553.467910] [<c07defe8>] (schedule_preempt_disabled) from [<c07e0bbc>] (mutex_lock_nested+0x1a0/0x3e8)
[  553.477254] [<c07e0a1c>] (mutex_lock_nested) from [<c03e927c>] (dpm_complete+0xc0/0x1b0)
[  553.485358]  r10:00561408 r9:edd3c054 r8:c0b4863c r7:edddbd90 r6:c0b485d8 r5:edd3c020
[  553.493313]  r4:edd3c0d0
[  553.495896] [<c03e91bc>] (dpm_complete) from [<c03e9388>] (dpm_resume_end+0x1c/0x20)
[  553.503652]  r9:00000000 r8:c0b1a9d0 r7:c1334ec0 r6:c1334edc r5:00000003 r4:00000010
[  553.511544] [<c03e936c>] (dpm_resume_end) from [<c0079894>] (suspend_devices_and_enter+0x158/0x504)
[  553.520604]  r4:00000000 r3:c1334efc
[  553.524250] [<c007973c>] (suspend_devices_and_enter) from [<c0079e74>] (pm_suspend+0x234/0x2cc)
[  553.532961]  r10:00561408 r9:ed6b7300 r8:00000004 r7:c1334eec r6:00000000 r5:c1334ee8
[  553.540914]  r4:00000003
[  553.543493] [<c0079c40>] (pm_suspend) from [<c0078a6c>] (state_store+0x6c/0xc0)

[  555.703684] 7 locks held by kworker/u2:13/826:
[  555.708140]  #0:  ("%s""ci_otg"){++++.+}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.716277]  SolidRun#1:  ((&ci->work)){+.+.+.}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.724317]  SolidRun#2:  (usb_bus_list_lock){+.+.+.}, at: [<c04ae5e4>] usb_remove_hcd+0x98/0x1ac
[  555.732626]  SolidRun#3:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.740403]  SolidRun#4:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.748179]  SolidRun#5:  (&dev->mutex){......}, at: [<c03dc2f4>] device_release_driver+0x20/0x34
[  555.756487]  SolidRun#6:  (&shost->scan_mutex){+.+.+.}, at: [<c04097d0>] scsi_remove_host+0x20/0x104

Cc: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Apr 26, 2016
…pt()

commit 7834c10 upstream.

Since 4.4, I've been able to trigger this occasionally:

===============================
[ INFO: suspicious RCU usage. ]
4.5.0-rc7-think+ SolidRun#3 Not tainted
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/20160315012054.GA17765@codemonkey.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------------------------------
./arch/x86/include/asm/msr-trace.h:47 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 1
RCU used illegally from extended quiescent state!
no locks held by swapper/3/0.

stack backtrace:
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.5.0-rc7-think+ SolidRun#3
 ffffffff92f821e0 1f3e5c340597d7fc ffff880468e07f10 ffffffff92560c2a
 ffff880462145280 0000000000000001 ffff880468e07f40 ffffffff921376a6
 ffffffff93665ea0 0000cc7c876d28da 0000000000000005 ffffffff9383dd60
Call Trace:
 <IRQ>  [<ffffffff92560c2a>] dump_stack+0x67/0x9d
 [<ffffffff921376a6>] lockdep_rcu_suspicious+0xe6/0x100
 [<ffffffff925ae7a7>] do_trace_write_msr+0x127/0x1a0
 [<ffffffff92061c83>] native_apic_msr_eoi_write+0x23/0x30
 [<ffffffff92054408>] smp_trace_call_function_interrupt+0x38/0x360
 [<ffffffff92d1ca60>] trace_call_function_interrupt+0x90/0xa0
 <EOI>  [<ffffffff92ac5124>] ? cpuidle_enter_state+0x1b4/0x520

Move the entering_irq() call before ack_APIC_irq(), because entering_irq()
tells the RCU susbstems to end the extended quiescent state, so that the
following trace call in ack_APIC_irq() works correctly.

Suggested-by: Andi Kleen <ak@linux.intel.com>
Fixes: 4787c36 "x86/tracing: Add irq_enter/exit() in smp_trace_reschedule_interrupt()"
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Apr 26, 2016
commit 9b29972 upstream.

Fix null pointer dereference by changing register_cache() to return an int
instead of being void.  This allows it to return -ENOMEM or -ENODEV and
enables upper layers to handle the OOM case without NULL pointer issues.

See this thread:
  http://thread.gmane.org/gmane.linux.kernel.bcache.devel/3521

Fixes this error:
  gargamel:/sys/block/md5/bcache# echo /dev/sdh2 > /sys/fs/bcache/register

  bcache: register_cache() error opening sdh2: cannot allocate memory
  BUG: unable to handle kernel NULL pointer dereference at 00000000000009b8
  IP: [<ffffffffc05a7e8d>] cache_set_flush+0x102/0x15c [bcache]
  PGD 120dff067 PUD 1119a3067 PMD 0
  Oops: 0000 [SolidRun#1] SMP
  Modules linked in: veth ip6table_filter ip6_tables
  (...)
  CPU: 4 PID: 3371 Comm: kworker/4:3 Not tainted 4.4.2-amd64-i915-volpreempt-20160213bc1 SolidRun#3
  Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 3904 04/27/2013
  Workqueue: events cache_set_flush [bcache]
  task: ffff88020d5dc280 ti: ffff88020b6f8000 task.ti: ffff88020b6f8000
  RIP: 0010:[<ffffffffc05a7e8d>]  [<ffffffffc05a7e8d>] cache_set_flush+0x102/0x15c [bcache]

Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request May 26, 2016
…ing"

commit 93f0750 upstream.

This patch causes a Kernel panic when called on a DVB driver.

This was also reported by David R <david@unsolicited.net>:

May  7 14:47:35 server kernel: [  501.247123] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
May  7 14:47:35 server kernel: [  501.247239] IP: [<ffffffffa0222c71>] __verify_planes_array.isra.3+0x1/0x80 [videobuf2_v4l2]
May  7 14:47:35 server kernel: [  501.247354] PGD cae6f067 PUD ca99c067 PMD 0
May  7 14:47:35 server kernel: [  501.247426] Oops: 0000 [SolidRun#1] SMP
May  7 14:47:35 server kernel: [  501.247482] Modules linked in: xfs tun xt_connmark xt_TCPMSS xt_tcpmss xt_owner xt_REDIRECT nf_nat_redirect xt_nat ipt_MASQUERADE nf_nat_masquerade_ipv4 ts_kmp ts_bm xt_string ipt_REJECT nf_reject_ipv4 xt_recent xt_conntrack xt_multiport xt_pkttype xt_tcpudp xt_mark nf_log_ipv4 nf_log_common xt_LOG xt_limit iptable_mangle iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_filter ip_tables ip6table_filter ip6_tables x_tables pppoe pppox dm_crypt ts2020 regmap_i2c ds3000 cx88_dvb dvb_pll cx88_vp3054_i2c mt352 videobuf2_dvb cx8800 cx8802 cx88xx pl2303 tveeprom videobuf2_dma_sg ppdev videobuf2_memops videobuf2_v4l2 videobuf2_core dvb_usb_digitv snd_hda_codec_via snd_hda_codec_hdmi snd_hda_codec_generic radeon dvb_usb snd_hda_intel amd64_edac_mod serio_raw snd_hda_codec edac_core fbcon k10temp bitblit softcursor snd_hda_core font snd_pcm_oss i2c_piix4 snd_mixer_oss tileblit drm_kms_helper syscopyarea snd_pcm snd_seq_dummy sysfillrect snd_seq_oss sysimgblt fb_sys_fops ttm snd_seq_midi r8169 snd_rawmidi drm snd_seq_midi_event e1000e snd_seq snd_seq_device snd_timer snd ptp pps_core i2c_algo_bit soundcore parport_pc ohci_pci shpchp tpm_tis tpm nfsd auth_rpcgss oid_registry hwmon_vid exportfs nfs_acl mii nfs bonding lockd grace lp sunrpc parport
May  7 14:47:35 server kernel: [  501.249564] CPU: 1 PID: 6889 Comm: vb2-cx88[0] Not tainted 4.5.3 SolidRun#3
May  7 14:47:35 server kernel: [  501.249644] Hardware name: System manufacturer System Product Name/M4A785TD-V EVO, BIOS 0211    07/08/2009
May  7 14:47:35 server kernel: [  501.249767] task: ffff8800aebf3600 ti: ffff8801e07a0000 task.ti: ffff8801e07a0000
May  7 14:47:35 server kernel: [  501.249861] RIP: 0010:[<ffffffffa0222c71>]  [<ffffffffa0222c71>] __verify_planes_array.isra.3+0x1/0x80 [videobuf2_v4l2]
May  7 14:47:35 server kernel: [  501.250002] RSP: 0018:ffff8801e07a3de8  EFLAGS: 00010086
May  7 14:47:35 server kernel: [  501.250071] RAX: 0000000000000283 RBX: ffff880210dc5000 RCX: 0000000000000283
May  7 14:47:35 server kernel: [  501.250161] RDX: ffffffffa0222cf0 RSI: 0000000000000000 RDI: ffff880210dc5014
May  7 14:47:35 server kernel: [  501.250251] RBP: ffff8801e07a3df8 R08: ffff8801e07a0000 R09: 0000000000000000
May  7 14:47:35 server kernel: [  501.250348] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800cda2a9d8
May  7 14:47:35 server kernel: [  501.250438] R13: ffff880210dc51b8 R14: 0000000000000000 R15: ffff8800cda2a828
May  7 14:47:35 server kernel: [  501.250528] FS:  00007f5b77fff700(0000) GS:ffff88021fc40000(0000) knlGS:00000000adaffb40
May  7 14:47:35 server kernel: [  501.250631] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
May  7 14:47:35 server kernel: [  501.250704] CR2: 0000000000000004 CR3: 00000000ca19d000 CR4: 00000000000006e0
May  7 14:47:35 server kernel: [  501.250794] Stack:
May  7 14:47:35 server kernel: [  501.250822]  ffff8801e07a3df8 ffffffffa0222cfd ffff8801e07a3e70 ffffffffa0236beb
May  7 14:47:35 server kernel: [  501.250937]  0000000000000283 ffff8801e07a3e94 0000000000000000 0000000000000000
May  7 14:47:35 server kernel: [  501.251051]  ffff8800aebf3600 ffffffff8108d8e0 ffff8801e07a3e38 ffff8801e07a3e38
May  7 14:47:35 server kernel: [  501.251165] Call Trace:
May  7 14:47:35 server kernel: [  501.251200]  [<ffffffffa0222cfd>] ? __verify_planes_array_core+0xd/0x10 [videobuf2_v4l2]
May  7 14:47:35 server kernel: [  501.251306]  [<ffffffffa0236beb>] vb2_core_dqbuf+0x2eb/0x4c0 [videobuf2_core]
May  7 14:47:35 server kernel: [  501.251398]  [<ffffffff8108d8e0>] ? prepare_to_wait_event+0x100/0x100
May  7 14:47:35 server kernel: [  501.251482]  [<ffffffffa023855b>] vb2_thread+0x1cb/0x220 [videobuf2_core]
May  7 14:47:35 server kernel: [  501.251569]  [<ffffffffa0238390>] ? vb2_core_qbuf+0x230/0x230 [videobuf2_core]
May  7 14:47:35 server kernel: [  501.251662]  [<ffffffffa0238390>] ? vb2_core_qbuf+0x230/0x230 [videobuf2_core]
May  7 14:47:35 server kernel: [  501.255982]  [<ffffffff8106f984>] kthread+0xc4/0xe0
May  7 14:47:35 server kernel: [  501.260292]  [<ffffffff8106f8c0>] ? kthread_park+0x50/0x50
May  7 14:47:35 server kernel: [  501.264615]  [<ffffffff81697a5f>] ret_from_fork+0x3f/0x70
May  7 14:47:35 server kernel: [  501.268962]  [<ffffffff8106f8c0>] ? kthread_park+0x50/0x50
May  7 14:47:35 server kernel: [  501.273216] Code: 0d 01 74 16 48 8b 46 28 48 8b 56 30 48 89 87 d0 01 00 00 48 89 97 d8 01 00 00 5d c3 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 <8b> 46 04 48 89 e5 8d 50 f7 31 c0 83 fa 01 76 02 5d c3 48 83 7e
May  7 14:47:35 server kernel: [  501.282146] RIP  [<ffffffffa0222c71>] __verify_planes_array.isra.3+0x1/0x80 [videobuf2_v4l2]
May  7 14:47:35 server kernel: [  501.286391]  RSP <ffff8801e07a3de8>
May  7 14:47:35 server kernel: [  501.290619] CR2: 0000000000000004
May  7 14:47:35 server kernel: [  501.294786] ---[ end trace b2b354153ccad110 ]---

This reverts commit 2c1f695.

Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Fixes: 2c1f695 ("[media] videobuf2-v4l2: Verify planes array in buffer dequeueing")
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Jun 4, 2016
commit b49b927 upstream.

We shouldn't be calling clk_prepare_enable()/clk_prepare_disable()
in an atomic context.

Fixes the following issue:

[    5.830970] ehci-omap: OMAP-EHCI Host Controller driver
[    5.830974] driver_register 'ehci-omap'
[    5.895849] driver_register 'wl1271_sdio'
[    5.896870] BUG: scheduling while atomic: udevd/994/0x00000002
[    5.896876] 4 locks held by udevd/994:
[    5.896904]  #0:  (&dev->mutex){......}, at: [<c049597c>] __driver_attach+0x60/0xac
[    5.896923]  SolidRun#1:  (&dev->mutex){......}, at: [<c049598c>] __driver_attach+0x70/0xac
[    5.896946]  SolidRun#2:  (tll_lock){+.+...}, at: [<c04c2630>] omap_tll_enable+0x2c/0xd0
[    5.896966]  SolidRun#3:  (prepare_lock){+.+...}, at: [<c05ce9c8>] clk_prepare_lock+0x48/0xe0
[    5.897042] Modules linked in: wlcore_sdio(+) ehci_omap(+) dwc3_omap snd_soc_ts3a225e leds_is31fl319x bq27xxx_battery_i2c tsc2007 bq27xxx_battery bq2429x_charger ina2xx tca8418_keypad as5013 leds_tca6507 twl6040_vibra gpio_twl6040 bmp085_i2c(+) palmas_gpadc usb3503 palmas_pwrbutton bmg160_i2c(+) bmp085 bma150(+) bmg160_core bmp280 input_polldev snd_soc_omap_mcbsp snd_soc_omap_mcpdm snd_soc_omap snd_pcm_dmaengine
[    5.897048] Preemption disabled at:[<  (null)>]   (null)
[    5.897051]
[    5.897059] CPU: 0 PID: 994 Comm: udevd Not tainted 4.6.0-rc5-letux+ Freescale#233
[    5.897062] Hardware name: Generic OMAP5 (Flattened Device Tree)
[    5.897076] [<c010e714>] (unwind_backtrace) from [<c010af34>] (show_stack+0x10/0x14)
[    5.897087] [<c010af34>] (show_stack) from [<c040aa7c>] (dump_stack+0x88/0xc0)
[    5.897099] [<c040aa7c>] (dump_stack) from [<c020c558>] (__schedule_bug+0xac/0xd0)
[    5.897111] [<c020c558>] (__schedule_bug) from [<c06f3d44>] (__schedule+0x88/0x7e4)
[    5.897120] [<c06f3d44>] (__schedule) from [<c06f46d8>] (schedule+0x9c/0xc0)
[    5.897129] [<c06f46d8>] (schedule) from [<c06f4904>] (schedule_preempt_disabled+0x14/0x20)
[    5.897140] [<c06f4904>] (schedule_preempt_disabled) from [<c06f64e4>] (mutex_lock_nested+0x258/0x43c)
[    5.897150] [<c06f64e4>] (mutex_lock_nested) from [<c05ce9c8>] (clk_prepare_lock+0x48/0xe0)
[    5.897160] [<c05ce9c8>] (clk_prepare_lock) from [<c05d0e7c>] (clk_prepare+0x10/0x28)
[    5.897169] [<c05d0e7c>] (clk_prepare) from [<c04c2668>] (omap_tll_enable+0x64/0xd0)
[    5.897180] [<c04c2668>] (omap_tll_enable) from [<c04c1728>] (usbhs_runtime_resume+0x18/0x17c)
[    5.897192] [<c04c1728>] (usbhs_runtime_resume) from [<c049d404>] (pm_generic_runtime_resume+0x2c/0x40)
[    5.897202] [<c049d404>] (pm_generic_runtime_resume) from [<c049f180>] (__rpm_callback+0x38/0x68)
[    5.897210] [<c049f180>] (__rpm_callback) from [<c049f220>] (rpm_callback+0x70/0x88)
[    5.897218] [<c049f220>] (rpm_callback) from [<c04a0a00>] (rpm_resume+0x4ec/0x7ec)
[    5.897227] [<c04a0a00>] (rpm_resume) from [<c04a0f48>] (__pm_runtime_resume+0x4c/0x64)
[    5.897236] [<c04a0f48>] (__pm_runtime_resume) from [<c04958dc>] (driver_probe_device+0x30/0x70)
[    5.897246] [<c04958dc>] (driver_probe_device) from [<c04959a4>] (__driver_attach+0x88/0xac)
[    5.897256] [<c04959a4>] (__driver_attach) from [<c04940f8>] (bus_for_each_dev+0x50/0x84)
[    5.897267] [<c04940f8>] (bus_for_each_dev) from [<c0494e40>] (bus_add_driver+0xcc/0x1e4)
[    5.897276] [<c0494e40>] (bus_add_driver) from [<c0496914>] (driver_register+0xac/0xf4)
[    5.897286] [<c0496914>] (driver_register) from [<c01018e0>] (do_one_initcall+0x100/0x1b8)
[    5.897296] [<c01018e0>] (do_one_initcall) from [<c01c7a54>] (do_init_module+0x58/0x1c0)
[    5.897304] [<c01c7a54>] (do_init_module) from [<c01c8a3c>] (SyS_finit_module+0x88/0x90)
[    5.897313] [<c01c8a3c>] (SyS_finit_module) from [<c0107120>] (ret_fast_syscall+0x0/0x1c)
[    5.912697] ------------[ cut here ]------------
[    5.912711] WARNING: CPU: 0 PID: 994 at kernel/sched/core.c:2996 _raw_spin_unlock+0x28/0x58
[    5.912717] DEBUG_LOCKS_WARN_ON(val > preempt_count())

Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Jun 28, 2016
…offline_kmem()

commit 3a06bb7 upstream.

memcg_offline_kmem() may be called from memcg_free_kmem() after a css
init failure.  memcg_free_kmem() is a ->css_free callback which is
called without cgroup_mutex and memcg_offline_kmem() ends up using
css_for_each_descendant_pre() without any locking.  Fix it by adding rcu
read locking around it.

    mkdir: cannot create directory `65530': No space left on device
    ===============================
    [ INFO: suspicious RCU usage. ]
    4.6.0-work+ Freescale#321 Not tainted
    -------------------------------
    kernel/cgroup.c:4008 cgroup_mutex or RCU read lock required!
     [  527.243970] other info that might help us debug this:
     [  527.244715]
    rcu_scheduler_active = 1, debug_locks = 0
    2 locks held by kworker/0:5/1664:
     #0:  ("cgroup_destroy"){.+.+..}, at: [<ffffffff81060ab5>] process_one_work+0x165/0x4a0
     SolidRun#1:  ((&css->destroy_work)SolidRun#3){+.+...}, at: [<ffffffff81060ab5>] process_one_work+0x165/0x4a0
     [  527.248098] stack backtrace:
    CPU: 0 PID: 1664 Comm: kworker/0:5 Not tainted 4.6.0-work+ Freescale#321
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014
    Workqueue: cgroup_destroy css_free_work_fn
    Call Trace:
      dump_stack+0x68/0xa1
      lockdep_rcu_suspicious+0xd7/0x110
      css_next_descendant_pre+0x7d/0xb0
      memcg_offline_kmem.part.44+0x4a/0xc0
      mem_cgroup_css_free+0x1ec/0x200
      css_free_work_fn+0x49/0x5e0
      process_one_work+0x1c5/0x4a0
      worker_thread+0x49/0x490
      kthread+0xea/0x100
      ret_from_fork+0x1f/0x40

Link: http://lkml.kernel.org/r/20160526203018.GG23194@mtj.duckdns.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Jun 28, 2016
commit 09d9686 upstream.

This looks like refactoring, but its also a bug fix.

Problem is that the compat path (32bit iptables, 64bit kernel) lacks a few
sanity tests that are done in the normal path.

For example, we do not check for underflows and the base chain policies.

While its possible to also add such checks to the compat path, its more
copy&pastry, for instance we cannot reuse check_underflow() helper as
e->target_offset differs in the compat case.

Other problem is that it makes auditing for validation errors harder; two
places need to be checked and kept in sync.

At a high level 32 bit compat works like this:
1- initial pass over blob:
   validate match/entry offsets, bounds checking
   lookup all matches and targets
   do bookkeeping wrt. size delta of 32/64bit structures
   assign match/target.u.kernel pointer (points at kernel
   implementation, needed to access ->compatsize etc.)

2- allocate memory according to the total bookkeeping size to
   contain the translated ruleset

3- second pass over original blob:
   for each entry, copy the 32bit representation to the newly allocated
   memory.  This also does any special match translations (e.g.
   adjust 32bit to 64bit longs, etc).

4- check if ruleset is free of loops (chase all jumps)

5-first pass over translated blob:
   call the checkentry function of all matches and targets.

The alternative implemented by this patch is to drop steps 3&4 from the
compat process, the translation is changed into an intermediate step
rather than a full 1:1 translate_table replacement.

In the 2nd pass (step SolidRun#3), change the 64bit ruleset back to a kernel
representation, i.e. put() the kernel pointer and restore ->u.user.name .

This gets us a 64bit ruleset that is in the format generated by a 64bit
iptables userspace -- we can then use translate_table() to get the
'native' sanity checks.

This has two drawbacks:

1. we re-validate all the match and target entry structure sizes even
though compat translation is supposed to never generate bogus offsets.
2. we put and then re-lookup each match and target.

THe upside is that we get all sanity tests and ruleset validations
provided by the normal path and can remove some duplicated compat code.

iptables-restore time of autogenerated ruleset with 300k chains of form
-A CHAIN0001 -m limit --limit 1/s -j CHAIN0002
-A CHAIN0002 -m limit --limit 1/s -j CHAIN0003

shows no noticeable differences in restore times:
old:   0m30.796s
new:   0m31.521s
64bit: 0m25.674s

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
commit 361cad3 upstream.

We've seen this in a packet capture - I've intermixed what I
think was going on. The fix here is to grab the so_lock sooner.

1964379 -> #1 open (for write) reply seqid=1
1964393 -> #2 open (for read) reply seqid=2

  __nfs4_close(), state->n_wronly--
  nfs4_state_set_mode_locked(), changes state->state = [R]
  state->flags is [RW]
  state->state is [R], state->n_wronly == 0, state->n_rdonly == 1

1964398 -> #3 open (for write) call -> because close is already running
1964399 -> downgrade (to read) call seqid=2 (close of #1)
1964402 -> #3 open (for write) reply seqid=3

 __update_open_stateid()
   nfs_set_open_stateid_locked(), changes state->flags
   state->flags is [RW]
   state->state is [R], state->n_wronly == 0, state->n_rdonly == 1
   new sequence number is exposed now via nfs4_stateid_copy()

   next step would be update_open_stateflags(), pending so_lock

1964403 -> downgrade reply seqid=2, fails with OLD_STATEID (close of #1)

   nfs4_close_prepare() gets so_lock and recalcs flags -> send close

1964405 -> downgrade (to read) call seqid=3 (close of #1 retry)

   __update_open_stateid() gets so_lock
 * update_open_stateflags() updates state->n_wronly.
   nfs4_state_set_mode_locked() updates state->state

   state->flags is [RW]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

 * should have suppressed the preceding nfs4_close_prepare() from
   sending open_downgrade

1964406 -> write call
1964408 -> downgrade (to read) reply seqid=4 (close of #1 retry)

   nfs_clear_open_stateid_locked()
   state->flags is [R]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

1964409 -> write reply (fails, openmode)

Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
commit 09dc9cd upstream.

The code produces the following trace:

[1750924.419007] general protection fault: 0000 [#3] SMP
[1750924.420364] Modules linked in: nfnetlink autofs4 rpcsec_gss_krb5 nfsv4
dcdbas rfcomm bnep bluetooth nfsd auth_rpcgss nfs_acl dm_multipath nfs lockd
scsi_dh sunrpc fscache radeon ttm drm_kms_helper drm serio_raw parport_pc
ppdev i2c_algo_bit lpc_ich ipmi_si ib_mthca ib_qib dca lp parport ib_ipoib
mac_hid ib_cm i3000_edac ib_sa ib_uverbs edac_core ib_umad ib_mad ib_core
ib_addr tg3 ptp dm_mirror dm_region_hash dm_log psmouse pps_core
[1750924.420364] CPU: 1 PID: 8401 Comm: python Tainted: G D
3.13.0-39-generic #66-Ubuntu
[1750924.420364] Hardware name: Dell Computer Corporation PowerEdge
860/0XM089, BIOS A04 07/24/2007
[1750924.420364] task: ffff8800366a9800 ti: ffff88007af1c000 task.ti:
ffff88007af1c000
[1750924.420364] RIP: 0010:[<ffffffffa0131d51>] [<ffffffffa0131d51>]
qib_mcast_qp_free+0x11/0x50 [ib_qib]
[1750924.420364] RSP: 0018:ffff88007af1dd70  EFLAGS: 00010246
[1750924.420364] RAX: 0000000000000001 RBX: ffff88007b822688 RCX:
000000000000000f
[1750924.420364] RDX: ffff88007b822688 RSI: ffff8800366c15a0 RDI:
6764697200000000
[1750924.420364] RBP: ffff88007af1dd78 R08: 0000000000000001 R09:
0000000000000000
[1750924.420364] R10: 0000000000000011 R11: 0000000000000246 R12:
ffff88007baa1d98
[1750924.420364] R13: ffff88003ecab000 R14: ffff88007b822660 R15:
0000000000000000
[1750924.420364] FS:  00007ffff7fd8740(0000) GS:ffff88007fc80000(0000)
knlGS:0000000000000000
[1750924.420364] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1750924.420364] CR2: 00007ffff597c750 CR3: 000000006860b000 CR4:
00000000000007e0
[1750924.420364] Stack:
[1750924.420364]  ffff88007b822688 ffff88007af1ddf0 ffffffffa0132429
000000007af1de20
[1750924.420364]  ffff88007baa1dc8 ffff88007baa0000 ffff88007af1de70
ffffffffa00cb313
[1750924.420364]  00007fffffffde88 0000000000000000 0000000000000008
ffff88003ecab000
[1750924.420364] Call Trace:
[1750924.420364]  [<ffffffffa0132429>] qib_multicast_detach+0x1e9/0x350
[ib_qib]
[1750924.568035]  [<ffffffffa00cb313>] ? ib_uverbs_modify_qp+0x323/0x3d0
[ib_uverbs]
[1750924.568035]  [<ffffffffa0092d61>] ib_detach_mcast+0x31/0x50 [ib_core]
[1750924.568035]  [<ffffffffa00cc213>] ib_uverbs_detach_mcast+0x93/0x170
[ib_uverbs]
[1750924.568035]  [<ffffffffa00c61f6>] ib_uverbs_write+0xc6/0x2c0 [ib_uverbs]
[1750924.568035]  [<ffffffff81312e68>] ? apparmor_file_permission+0x18/0x20
[1750924.568035]  [<ffffffff812d4cd3>] ? security_file_permission+0x23/0xa0
[1750924.568035]  [<ffffffff811bd214>] vfs_write+0xb4/0x1f0
[1750924.568035]  [<ffffffff811bdc49>] SyS_write+0x49/0xa0
[1750924.568035]  [<ffffffff8172f7ed>] system_call_fastpath+0x1a/0x1f
[1750924.568035] Code: 66 2e 0f 1f 84 00 00 00 00 00 31 c0 5d c3 66 2e 0f 1f
84 00 00 00 00 00 66 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 10
<f0> ff 8f 40 01 00 00 74 0e 48 89 df e8 8e f8 06 e1 5b 5d c3 0f
[1750924.568035] RIP  [<ffffffffa0131d51>] qib_mcast_qp_free+0x11/0x50
[ib_qib]
[1750924.568035]  RSP <ffff88007af1dd70>
[1750924.650439] ---[ end trace 73d5d4b3f8ad4851 ]

The fix is to note the qib_mcast_qp that was found.   If none is found, then
return EINVAL indicating the error.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
commit d144dfe upstream.

If we use USB ID pin as wakeup source, and there is a USB block
device on this USB OTG (ID) cable, the system will be deadlock
after system resume.

The root cause for this problem is: the workqueue ci_otg may try
to remove hcd before the driver resume has finished, and hcd will
disconnect the device on it, then, it will call device_release_driver,
and holds the device lock "dev->mutex", but it is never unlocked since
it waits workqueue writeback to run to flush the block information, but
the workqueue writeback is freezable, it is not thawed before driver
resume has finished.

When the driver (device: sd 0:0:0:0:) resume goes to dpm_complete, it
tries to get its device lock "dev->mutex", but it can't get it forever,
then the deadlock occurs. Below call stacks show the situation.

So, in order to fix this problem, we need to change workqueue ci_otg
as freezable, then the work item in this workqueue will be run after
driver's resume, this workqueue will not be blocked forever like above
case since the workqueue writeback has been thawed too.

Tested at: i.mx6qdl-sabresd and i.mx6sx-sdb.

[  555.178869] kworker/u2:13   D c07de74c     0   826      2 0x00000000
[  555.185310] Workqueue: ci_otg ci_otg_work
[  555.189353] Backtrace:
[  555.191849] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  555.198912]  r10:ee471ba0 r9:00000000 r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4
[  555.206867]  r4:ee470000
[  555.209453] [<c07dec24>] (schedule) from [<c07e2fc4>] (schedule_timeout+0x15c/0x1e0)
[  555.217212]  r4:7fffffff r3:edc2b000
[  555.220862] [<c07e2e68>] (schedule_timeout) from [<c07df6c8>] (wait_for_common+0x94/0x144)
[  555.229140]  r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 r4:7fffffff
[  555.235980] [<c07df634>] (wait_for_common) from [<c07df790>] (wait_for_completion+0x18/0x1c)
[  555.244430]  r10:00000001 r9:c0b5563c r8:c0042e48 r7:ef086000 r6:eea4372c r5:ef131b00
[  555.252383]  r4:00000000
[  555.254970] [<c07df778>] (wait_for_completion) from [<c0043cb8>] (flush_work+0x19c/0x234)
[  555.263177] [<c0043b1c>] (flush_work) from [<c0043fac>] (flush_delayed_work+0x48/0x4c)
[  555.271106]  r8:ed5b5000 r7:c0b38a3c r6:eea439cc r5:eea4372c r4:eea4372c
[  555.277958] [<c0043f64>] (flush_delayed_work) from [<c00eae18>] (bdi_unregister+0x84/0xec)
[  555.286236]  r4:eea43520 r3:20000153
[  555.289885] [<c00ead94>] (bdi_unregister) from [<c02c2154>] (blk_cleanup_queue+0x180/0x29c)
[  555.298250]  r5:eea43808 r4:eea43400
[  555.301909] [<c02c1fd4>] (blk_cleanup_queue) from [<c0417914>] (__scsi_remove_device+0x48/0xb8)
[  555.310623]  r7:00000000 r6:20000153 r5:ededa950 r4:ededa800
[  555.316403] [<c04178cc>] (__scsi_remove_device) from [<c0415e90>] (scsi_forget_host+0x64/0x68)
[  555.325028]  r5:ededa800 r4:ed5b5000
[  555.328689] [<c0415e2c>] (scsi_forget_host) from [<c0409828>] (scsi_remove_host+0x78/0x104)
[  555.337054]  r5:ed5b5068 r4:ed5b5000
[  555.340709] [<c04097b0>] (scsi_remove_host) from [<c04cdfcc>] (usb_stor_disconnect+0x50/0xb4)
[  555.349247]  r6:ed5b56e4 r5:ed5b5818 r4:ed5b5690 r3:00000008
[  555.355025] [<c04cdf7c>] (usb_stor_disconnect) from [<c04b3bc8>] (usb_unbind_interface+0x78/0x25c)
[  555.363997]  r8:c13919b4 r7:edd3c000 r6:edd3c020 r5:ee551c68 r4:ee551c00 r3:c04cdf7c
[  555.371892] [<c04b3b50>] (usb_unbind_interface) from [<c03dc248>] (__device_release_driver+0x8c/0x118)
[  555.381213]  r10:00000001 r9:edd90c00 r8:c13919b4 r7:ee551c68 r6:c0b546e0 r5:c0b5563c
[  555.389167]  r4:edd3c020
[  555.391752] [<c03dc1bc>] (__device_release_driver) from [<c03dc2fc>] (device_release_driver+0x28/0x34)
[  555.401071]  r5:edd3c020 r4:edd3c054
[  555.404721] [<c03dc2d4>] (device_release_driver) from [<c03db304>] (bus_remove_device+0xe0/0x110)
[  555.413607]  r5:edd3c020 r4:ef17f04c
[  555.417253] [<c03db224>] (bus_remove_device) from [<c03d8128>] (device_del+0x114/0x21c)
[  555.425270]  r6:edd3c028 r5:edd3c020 r4:ee551c00 r3:00000000
[  555.431045] [<c03d8014>] (device_del) from [<c04b1560>] (usb_disable_device+0xa4/0x1e8)
[  555.439061]  r8:edd3c000 r7:eded8000 r6:00000000 r5:00000001 r4:ee551c00
[  555.445906] [<c04b14bc>] (usb_disable_device) from [<c04a8e54>] (usb_disconnect+0x74/0x224)
[  555.454271]  r9:edd90c00 r8:ee551000 r7:ee551c68 r6:ee551c9c r5:ee551c00 r4:00000001
[  555.462156] [<c04a8de0>] (usb_disconnect) from [<c04a8fb8>] (usb_disconnect+0x1d8/0x224)
[  555.470259]  r10:00000001 r9:edd90000 r8:ee471e2c r7:ee551468 r6:ee55149c r5:ee551400
[  555.478213]  r4:00000001
[  555.480797] [<c04a8de0>] (usb_disconnect) from [<c04ae5ec>] (usb_remove_hcd+0xa0/0x1ac)
[  555.488813]  r10:00000001 r9:ee471eb0 r8:00000000 r7:ef3d9500 r6:eded810c r5:eded80b0
[  555.496765]  r4:eded8000
[  555.499351] [<c04ae54c>] (usb_remove_hcd) from [<c04d4158>] (host_stop+0x28/0x64)
[  555.506847]  r6:eeb50010 r5:eded8000 r4:eeb51010
[  555.511563] [<c04d4130>] (host_stop) from [<c04d09b8>] (ci_otg_work+0xc4/0x124)
[  555.518885]  r6:00000001 r5:eeb50010 r4:eeb502a0 r3:c04d4130
[  555.524665] [<c04d08f4>] (ci_otg_work) from [<c00454f0>] (process_one_work+0x194/0x420)
[  555.532682]  r6:ef086000 r5:eeb502a0 r4:edc44480
[  555.537393] [<c004535c>] (process_one_work) from [<c00457b0>] (worker_thread+0x34/0x514)
[  555.545496]  r10:edc44480 r9:ef086000 r8:c0b1a100 r7:ef086034 r6:00000088 r5:edc44498
[  555.553450]  r4:ef086000
[  555.556032] [<c004577c>] (worker_thread) from [<c004bab4>] (kthread+0xdc/0xf8)
[  555.563268]  r10:00000000 r9:00000000 r8:00000000 r7:c004577c r6:edc44480 r5:eddc15c0
[  555.571221]  r4:00000000
[  555.573804] [<c004b9d8>] (kthread) from [<c000fef0>] (ret_from_fork+0x14/0x24)
[  555.581040]  r7:00000000 r6:00000000 r5:c004b9d8 r4:eddc15c0

[  553.429383] sh              D c07de74c     0   694    691 0x00000000
[  553.435801] Backtrace:
[  553.438295] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  553.445358]  r10:edd3c054 r9:edd3c078 r8:edddbd50 r7:edcbbc00 r6:c1377c34 r5:60000153
[  553.453313]  r4:eddda000
[  553.455896] [<c07dec24>] (schedule) from [<c07deff8>] (schedule_preempt_disabled+0x10/0x14)
[  553.464261]  r4:edd3c058 r3:0000000a
[  553.467910] [<c07defe8>] (schedule_preempt_disabled) from [<c07e0bbc>] (mutex_lock_nested+0x1a0/0x3e8)
[  553.477254] [<c07e0a1c>] (mutex_lock_nested) from [<c03e927c>] (dpm_complete+0xc0/0x1b0)
[  553.485358]  r10:00561408 r9:edd3c054 r8:c0b4863c r7:edddbd90 r6:c0b485d8 r5:edd3c020
[  553.493313]  r4:edd3c0d0
[  553.495896] [<c03e91bc>] (dpm_complete) from [<c03e9388>] (dpm_resume_end+0x1c/0x20)
[  553.503652]  r9:00000000 r8:c0b1a9d0 r7:c1334ec0 r6:c1334edc r5:00000003 r4:00000010
[  553.511544] [<c03e936c>] (dpm_resume_end) from [<c0079894>] (suspend_devices_and_enter+0x158/0x504)
[  553.520604]  r4:00000000 r3:c1334efc
[  553.524250] [<c007973c>] (suspend_devices_and_enter) from [<c0079e74>] (pm_suspend+0x234/0x2cc)
[  553.532961]  r10:00561408 r9:ed6b7300 r8:00000004 r7:c1334eec r6:00000000 r5:c1334ee8
[  553.540914]  r4:00000003
[  553.543493] [<c0079c40>] (pm_suspend) from [<c0078a6c>] (state_store+0x6c/0xc0)

[  555.703684] 7 locks held by kworker/u2:13/826:
[  555.708140]  #0:  ("%s""ci_otg"){++++.+}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.716277]  #1:  ((&ci->work)){+.+.+.}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.724317]  #2:  (usb_bus_list_lock){+.+.+.}, at: [<c04ae5e4>] usb_remove_hcd+0x98/0x1ac
[  555.732626]  #3:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.740403]  #4:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.748179]  #5:  (&dev->mutex){......}, at: [<c03dc2f4>] device_release_driver+0x20/0x34
[  555.756487]  #6:  (&shost->scan_mutex){+.+.+.}, at: [<c04097d0>] scsi_remove_host+0x20/0x104

Cc: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
…pt()

commit 7834c10 upstream.

Since 4.4, I've been able to trigger this occasionally:

===============================
[ INFO: suspicious RCU usage. ]
4.5.0-rc7-think+ #3 Not tainted
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/20160315012054.GA17765@codemonkey.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------------------------------
./arch/x86/include/asm/msr-trace.h:47 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 1
RCU used illegally from extended quiescent state!
no locks held by swapper/3/0.

stack backtrace:
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.5.0-rc7-think+ #3
 ffffffff92f821e0 1f3e5c340597d7fc ffff880468e07f10 ffffffff92560c2a
 ffff880462145280 0000000000000001 ffff880468e07f40 ffffffff921376a6
 ffffffff93665ea0 0000cc7c876d28da 0000000000000005 ffffffff9383dd60
Call Trace:
 <IRQ>  [<ffffffff92560c2a>] dump_stack+0x67/0x9d
 [<ffffffff921376a6>] lockdep_rcu_suspicious+0xe6/0x100
 [<ffffffff925ae7a7>] do_trace_write_msr+0x127/0x1a0
 [<ffffffff92061c83>] native_apic_msr_eoi_write+0x23/0x30
 [<ffffffff92054408>] smp_trace_call_function_interrupt+0x38/0x360
 [<ffffffff92d1ca60>] trace_call_function_interrupt+0x90/0xa0
 <EOI>  [<ffffffff92ac5124>] ? cpuidle_enter_state+0x1b4/0x520

Move the entering_irq() call before ack_APIC_irq(), because entering_irq()
tells the RCU susbstems to end the extended quiescent state, so that the
following trace call in ack_APIC_irq() works correctly.

Suggested-by: Andi Kleen <ak@linux.intel.com>
Fixes: 4787c36 "x86/tracing: Add irq_enter/exit() in smp_trace_reschedule_interrupt()"
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
commit b49b927 upstream.

We shouldn't be calling clk_prepare_enable()/clk_prepare_disable()
in an atomic context.

Fixes the following issue:

[    5.830970] ehci-omap: OMAP-EHCI Host Controller driver
[    5.830974] driver_register 'ehci-omap'
[    5.895849] driver_register 'wl1271_sdio'
[    5.896870] BUG: scheduling while atomic: udevd/994/0x00000002
[    5.896876] 4 locks held by udevd/994:
[    5.896904]  #0:  (&dev->mutex){......}, at: [<c049597c>] __driver_attach+0x60/0xac
[    5.896923]  #1:  (&dev->mutex){......}, at: [<c049598c>] __driver_attach+0x70/0xac
[    5.896946]  #2:  (tll_lock){+.+...}, at: [<c04c2630>] omap_tll_enable+0x2c/0xd0
[    5.896966]  #3:  (prepare_lock){+.+...}, at: [<c05ce9c8>] clk_prepare_lock+0x48/0xe0
[    5.897042] Modules linked in: wlcore_sdio(+) ehci_omap(+) dwc3_omap snd_soc_ts3a225e leds_is31fl319x bq27xxx_battery_i2c tsc2007 bq27xxx_battery bq2429x_charger ina2xx tca8418_keypad as5013 leds_tca6507 twl6040_vibra gpio_twl6040 bmp085_i2c(+) palmas_gpadc usb3503 palmas_pwrbutton bmg160_i2c(+) bmp085 bma150(+) bmg160_core bmp280 input_polldev snd_soc_omap_mcbsp snd_soc_omap_mcpdm snd_soc_omap snd_pcm_dmaengine
[    5.897048] Preemption disabled at:[<  (null)>]   (null)
[    5.897051]
[    5.897059] CPU: 0 PID: 994 Comm: udevd Not tainted 4.6.0-rc5-letux+ Freescale#233
[    5.897062] Hardware name: Generic OMAP5 (Flattened Device Tree)
[    5.897076] [<c010e714>] (unwind_backtrace) from [<c010af34>] (show_stack+0x10/0x14)
[    5.897087] [<c010af34>] (show_stack) from [<c040aa7c>] (dump_stack+0x88/0xc0)
[    5.897099] [<c040aa7c>] (dump_stack) from [<c020c558>] (__schedule_bug+0xac/0xd0)
[    5.897111] [<c020c558>] (__schedule_bug) from [<c06f3d44>] (__schedule+0x88/0x7e4)
[    5.897120] [<c06f3d44>] (__schedule) from [<c06f46d8>] (schedule+0x9c/0xc0)
[    5.897129] [<c06f46d8>] (schedule) from [<c06f4904>] (schedule_preempt_disabled+0x14/0x20)
[    5.897140] [<c06f4904>] (schedule_preempt_disabled) from [<c06f64e4>] (mutex_lock_nested+0x258/0x43c)
[    5.897150] [<c06f64e4>] (mutex_lock_nested) from [<c05ce9c8>] (clk_prepare_lock+0x48/0xe0)
[    5.897160] [<c05ce9c8>] (clk_prepare_lock) from [<c05d0e7c>] (clk_prepare+0x10/0x28)
[    5.897169] [<c05d0e7c>] (clk_prepare) from [<c04c2668>] (omap_tll_enable+0x64/0xd0)
[    5.897180] [<c04c2668>] (omap_tll_enable) from [<c04c1728>] (usbhs_runtime_resume+0x18/0x17c)
[    5.897192] [<c04c1728>] (usbhs_runtime_resume) from [<c049d404>] (pm_generic_runtime_resume+0x2c/0x40)
[    5.897202] [<c049d404>] (pm_generic_runtime_resume) from [<c049f180>] (__rpm_callback+0x38/0x68)
[    5.897210] [<c049f180>] (__rpm_callback) from [<c049f220>] (rpm_callback+0x70/0x88)
[    5.897218] [<c049f220>] (rpm_callback) from [<c04a0a00>] (rpm_resume+0x4ec/0x7ec)
[    5.897227] [<c04a0a00>] (rpm_resume) from [<c04a0f48>] (__pm_runtime_resume+0x4c/0x64)
[    5.897236] [<c04a0f48>] (__pm_runtime_resume) from [<c04958dc>] (driver_probe_device+0x30/0x70)
[    5.897246] [<c04958dc>] (driver_probe_device) from [<c04959a4>] (__driver_attach+0x88/0xac)
[    5.897256] [<c04959a4>] (__driver_attach) from [<c04940f8>] (bus_for_each_dev+0x50/0x84)
[    5.897267] [<c04940f8>] (bus_for_each_dev) from [<c0494e40>] (bus_add_driver+0xcc/0x1e4)
[    5.897276] [<c0494e40>] (bus_add_driver) from [<c0496914>] (driver_register+0xac/0xf4)
[    5.897286] [<c0496914>] (driver_register) from [<c01018e0>] (do_one_initcall+0x100/0x1b8)
[    5.897296] [<c01018e0>] (do_one_initcall) from [<c01c7a54>] (do_init_module+0x58/0x1c0)
[    5.897304] [<c01c7a54>] (do_init_module) from [<c01c8a3c>] (SyS_finit_module+0x88/0x90)
[    5.897313] [<c01c8a3c>] (SyS_finit_module) from [<c0107120>] (ret_fast_syscall+0x0/0x1c)
[    5.912697] ------------[ cut here ]------------
[    5.912711] WARNING: CPU: 0 PID: 994 at kernel/sched/core.c:2996 _raw_spin_unlock+0x28/0x58
[    5.912717] DEBUG_LOCKS_WARN_ON(val > preempt_count())

Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
linux4kix pushed a commit that referenced this pull request Oct 20, 2016
commit 09d9686 upstream.

This looks like refactoring, but its also a bug fix.

Problem is that the compat path (32bit iptables, 64bit kernel) lacks a few
sanity tests that are done in the normal path.

For example, we do not check for underflows and the base chain policies.

While its possible to also add such checks to the compat path, its more
copy&pastry, for instance we cannot reuse check_underflow() helper as
e->target_offset differs in the compat case.

Other problem is that it makes auditing for validation errors harder; two
places need to be checked and kept in sync.

At a high level 32 bit compat works like this:
1- initial pass over blob:
   validate match/entry offsets, bounds checking
   lookup all matches and targets
   do bookkeeping wrt. size delta of 32/64bit structures
   assign match/target.u.kernel pointer (points at kernel
   implementation, needed to access ->compatsize etc.)

2- allocate memory according to the total bookkeeping size to
   contain the translated ruleset

3- second pass over original blob:
   for each entry, copy the 32bit representation to the newly allocated
   memory.  This also does any special match translations (e.g.
   adjust 32bit to 64bit longs, etc).

4- check if ruleset is free of loops (chase all jumps)

5-first pass over translated blob:
   call the checkentry function of all matches and targets.

The alternative implemented by this patch is to drop steps 3&4 from the
compat process, the translation is changed into an intermediate step
rather than a full 1:1 translate_table replacement.

In the 2nd pass (step #3), change the 64bit ruleset back to a kernel
representation, i.e. put() the kernel pointer and restore ->u.user.name .

This gets us a 64bit ruleset that is in the format generated by a 64bit
iptables userspace -- we can then use translate_table() to get the
'native' sanity checks.

This has two drawbacks:

1. we re-validate all the match and target entry structure sizes even
though compat translation is supposed to never generate bogus offsets.
2. we put and then re-lookup each match and target.

THe upside is that we get all sanity tests and ruleset validations
provided by the normal path and can remove some duplicated compat code.

iptables-restore time of autogenerated ruleset with 300k chains of form
-A CHAIN0001 -m limit --limit 1/s -j CHAIN0002
-A CHAIN0002 -m limit --limit 1/s -j CHAIN0003

shows no noticeable differences in restore times:
old:   0m30.796s
new:   0m31.521s
64bit: 0m25.674s

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mk01 pushed a commit to mk01/linux-fslc that referenced this pull request Jan 8, 2017
commit 0ccd052 upstream.

btrfs_show_devname() is using the device_list_mutex, sometimes
a call to blkdev_put() leads vfs calling into this func. So
call blkdev_put() outside of device_list_mutex, as of now.

[  983.284212] ======================================================
[  983.290401] [ INFO: possible circular locking dependency detected ]
[  983.296677] 4.8.0-rc5-ceph-00023-g1b39cec2 SolidRun#1 Not tainted
[  983.302081] -------------------------------------------------------
[  983.308357] umount/21720 is trying to acquire lock:
[  983.313243]  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff9128ec51>] blkdev_put+0x31/0x150
[  983.321264]
[  983.321264] but task is already holding lock:
[  983.327101]  (&fs_devs->device_list_mutex){+.+...}, at: [<ffffffffc033d6f6>] __btrfs_close_devices+0x46/0x200 [btrfs]
[  983.337839]
[  983.337839] which lock already depends on the new lock.
[  983.337839]
[  983.346024]
[  983.346024] the existing dependency chain (in reverse order) is:
[  983.353512]
-> SolidRun#4 (&fs_devs->device_list_mutex){+.+...}:
[  983.359096]        [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.365143]        [<ffffffff91823125>] mutex_lock_nested+0x65/0x350
[  983.371521]        [<ffffffffc02d8116>] btrfs_show_devname+0x36/0x1f0 [btrfs]
[  983.378710]        [<ffffffff9129523e>] show_vfsmnt+0x4e/0x150
[  983.384593]        [<ffffffff9126ffc7>] m_show+0x17/0x20
[  983.389957]        [<ffffffff91276405>] seq_read+0x2b5/0x3b0
[  983.395669]        [<ffffffff9124c808>] __vfs_read+0x28/0x100
[  983.401464]        [<ffffffff9124eb3b>] vfs_read+0xab/0x150
[  983.407080]        [<ffffffff9124ec32>] SyS_read+0x52/0xb0
[  983.412609]        [<ffffffff91825fc0>] entry_SYSCALL_64_fastpath+0x23/0xc1
[  983.419617]
-> SolidRun#3 (namespace_sem){++++++}:
[  983.424024]        [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.430074]        [<ffffffff918239e9>] down_write+0x49/0x80
[  983.435785]        [<ffffffff91272457>] lock_mount+0x67/0x1c0
[  983.441582]        [<ffffffff91272ab2>] do_add_mount+0x32/0xf0
[  983.447458]        [<ffffffff9127363a>] finish_automount+0x5a/0xc0
[  983.453682]        [<ffffffff91259513>] follow_managed+0x1b3/0x2a0
[  983.459912]        [<ffffffff9125b750>] lookup_fast+0x300/0x350
[  983.465875]        [<ffffffff9125d6e7>] path_openat+0x3a7/0xaa0
[  983.471846]        [<ffffffff9125ef75>] do_filp_open+0x85/0xe0
[  983.477731]        [<ffffffff9124c41c>] do_sys_open+0x14c/0x1f0
[  983.483702]        [<ffffffff9124c4de>] SyS_open+0x1e/0x20
[  983.489240]        [<ffffffff91825fc0>] entry_SYSCALL_64_fastpath+0x23/0xc1
[  983.496254]
-> SolidRun#2 (&sb->s_type->i_mutex_key#3){+.+.+.}:
[  983.501798]        [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.507855]        [<ffffffff918239e9>] down_write+0x49/0x80
[  983.513558]        [<ffffffff91366237>] start_creating+0x87/0x100
[  983.519703]        [<ffffffff91366647>] debugfs_create_dir+0x17/0x100
[  983.526195]        [<ffffffff911df153>] bdi_register+0x93/0x210
[  983.532165]        [<ffffffff911df313>] bdi_register_owner+0x43/0x70
[  983.538570]        [<ffffffff914080fb>] device_add_disk+0x1fb/0x450
[  983.544888]        [<ffffffff91580226>] loop_add+0x1e6/0x290
[  983.550596]        [<ffffffff91fec358>] loop_init+0x10b/0x14f
[  983.556394]        [<ffffffff91002207>] do_one_initcall+0xa7/0x180
[  983.562618]        [<ffffffff91f932e0>] kernel_init_freeable+0x1cc/0x266
[  983.569370]        [<ffffffff918174be>] kernel_init+0xe/0x100
[  983.575166]        [<ffffffff9182620f>] ret_from_fork+0x1f/0x40
[  983.581131]
-> SolidRun#1 (loop_index_mutex){+.+.+.}:
[  983.585801]        [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.591858]        [<ffffffff91823125>] mutex_lock_nested+0x65/0x350
[  983.598256]        [<ffffffff9157ed3f>] lo_open+0x1f/0x60
[  983.603704]        [<ffffffff9128eec3>] __blkdev_get+0x123/0x400
[  983.609757]        [<ffffffff9128f4ea>] blkdev_get+0x34a/0x350
[  983.615639]        [<ffffffff9128f554>] blkdev_open+0x64/0x80
[  983.621428]        [<ffffffff9124aff6>] do_dentry_open+0x1c6/0x2d0
[  983.627651]        [<ffffffff9124c029>] vfs_open+0x69/0x80
[  983.633181]        [<ffffffff9125db74>] path_openat+0x834/0xaa0
[  983.639152]        [<ffffffff9125ef75>] do_filp_open+0x85/0xe0
[  983.645035]        [<ffffffff9124c41c>] do_sys_open+0x14c/0x1f0
[  983.650999]        [<ffffffff9124c4de>] SyS_open+0x1e/0x20
[  983.656535]        [<ffffffff91825fc0>] entry_SYSCALL_64_fastpath+0x23/0xc1
[  983.663541]
-> #0 (&bdev->bd_mutex){+.+.+.}:
[  983.668107]        [<ffffffff910def43>] __lock_acquire+0x1003/0x17b0
[  983.674510]        [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.680561]        [<ffffffff91823125>] mutex_lock_nested+0x65/0x350
[  983.686967]        [<ffffffff9128ec51>] blkdev_put+0x31/0x150
[  983.692761]        [<ffffffffc033481f>] btrfs_close_bdev+0x4f/0x60 [btrfs]
[  983.699699]        [<ffffffffc033d77b>] __btrfs_close_devices+0xcb/0x200 [btrfs]
[  983.707178]        [<ffffffffc033d8db>] btrfs_close_devices+0x2b/0xa0 [btrfs]
[  983.714380]        [<ffffffffc03081c5>] close_ctree+0x265/0x340 [btrfs]
[  983.721061]        [<ffffffffc02d7959>] btrfs_put_super+0x19/0x20 [btrfs]
[  983.727908]        [<ffffffff91250e2f>] generic_shutdown_super+0x6f/0x100
[  983.734744]        [<ffffffff91250f56>] kill_anon_super+0x16/0x30
[  983.740888]        [<ffffffffc02da97e>] btrfs_kill_super+0x1e/0x130 [btrfs]
[  983.747909]        [<ffffffff91250fe9>] deactivate_locked_super+0x49/0x80
[  983.754745]        [<ffffffff912515fd>] deactivate_super+0x5d/0x70
[  983.760977]        [<ffffffff91270a1c>] cleanup_mnt+0x5c/0x80
[  983.766773]        [<ffffffff91270a92>] __cleanup_mnt+0x12/0x20
[  983.772738]        [<ffffffff910aa2fe>] task_work_run+0x7e/0xc0
[  983.778708]        [<ffffffff91081b5a>] exit_to_usermode_loop+0x7e/0xb4
[  983.785373]        [<ffffffff910039eb>] syscall_return_slowpath+0xbb/0xd0
[  983.792212]        [<ffffffff9182605c>] entry_SYSCALL_64_fastpath+0xbf/0xc1
[  983.799225]
[  983.799225] other info that might help us debug this:
[  983.799225]
[  983.807291] Chain exists of:
  &bdev->bd_mutex --> namespace_sem --> &fs_devs->device_list_mutex

[  983.816521]  Possible unsafe locking scenario:
[  983.816521]
[  983.822489]        CPU0                    CPU1
[  983.827043]        ----                    ----
[  983.831599]   lock(&fs_devs->device_list_mutex);
[  983.836289]                                lock(namespace_sem);
[  983.842268]                                lock(&fs_devs->device_list_mutex);
[  983.849478]   lock(&bdev->bd_mutex);
[  983.853127]
[  983.853127]  *** DEADLOCK ***
[  983.853127]
[  983.859113] 3 locks held by umount/21720:
[  983.863145]  #0:  (&type->s_umount_key#35){++++..}, at: [<ffffffff912515f5>] deactivate_super+0x55/0x70
[  983.872713]  SolidRun#1:  (uuid_mutex){+.+.+.}, at: [<ffffffffc033d8d3>] btrfs_close_devices+0x23/0xa0 [btrfs]
[  983.882206]  SolidRun#2:  (&fs_devs->device_list_mutex){+.+...}, at: [<ffffffffc033d6f6>] __btrfs_close_devices+0x46/0x200 [btrfs]
[  983.893422]
[  983.893422] stack backtrace:
[  983.897824] CPU: 6 PID: 21720 Comm: umount Not tainted 4.8.0-rc5-ceph-00023-g1b39cec2 SolidRun#1
[  983.905958] Hardware name: Supermicro SYS-5018R-WR/X10SRW-F, BIOS 1.0c 09/07/2015
[  983.913492]  0000000000000000 ffff8c8a53c17a38 ffffffff91429521 ffffffff9260f4f0
[  983.921018]  ffffffff92642760 ffff8c8a53c17a88 ffffffff911b2b04 0000000000000050
[  983.928542]  ffffffff9237d620 ffff8c8a5294aee0 ffff8c8a5294aeb8 ffff8c8a5294aee0
[  983.936072] Call Trace:
[  983.938545]  [<ffffffff91429521>] dump_stack+0x85/0xc4
[  983.943715]  [<ffffffff911b2b04>] print_circular_bug+0x1fb/0x20c
[  983.949748]  [<ffffffff910def43>] __lock_acquire+0x1003/0x17b0
[  983.955613]  [<ffffffff910dfd0c>] lock_acquire+0x1bc/0x1f0
[  983.961123]  [<ffffffff9128ec51>] ? blkdev_put+0x31/0x150
[  983.966550]  [<ffffffff91823125>] mutex_lock_nested+0x65/0x350
[  983.972407]  [<ffffffff9128ec51>] ? blkdev_put+0x31/0x150
[  983.977832]  [<ffffffff9128ec51>] blkdev_put+0x31/0x150
[  983.983101]  [<ffffffffc033481f>] btrfs_close_bdev+0x4f/0x60 [btrfs]
[  983.989500]  [<ffffffffc033d77b>] __btrfs_close_devices+0xcb/0x200 [btrfs]
[  983.996415]  [<ffffffffc033d8db>] btrfs_close_devices+0x2b/0xa0 [btrfs]
[  984.003068]  [<ffffffffc03081c5>] close_ctree+0x265/0x340 [btrfs]
[  984.009189]  [<ffffffff9126cc5e>] ? evict_inodes+0x15e/0x170
[  984.014881]  [<ffffffffc02d7959>] btrfs_put_super+0x19/0x20 [btrfs]
[  984.021176]  [<ffffffff91250e2f>] generic_shutdown_super+0x6f/0x100
[  984.027476]  [<ffffffff91250f56>] kill_anon_super+0x16/0x30
[  984.033082]  [<ffffffffc02da97e>] btrfs_kill_super+0x1e/0x130 [btrfs]
[  984.039548]  [<ffffffff91250fe9>] deactivate_locked_super+0x49/0x80
[  984.045839]  [<ffffffff912515fd>] deactivate_super+0x5d/0x70
[  984.051525]  [<ffffffff91270a1c>] cleanup_mnt+0x5c/0x80
[  984.056774]  [<ffffffff91270a92>] __cleanup_mnt+0x12/0x20
[  984.062201]  [<ffffffff910aa2fe>] task_work_run+0x7e/0xc0
[  984.067625]  [<ffffffff91081b5a>] exit_to_usermode_loop+0x7e/0xb4
[  984.073747]  [<ffffffff910039eb>] syscall_return_slowpath+0xbb/0xd0
[  984.080038]  [<ffffffff9182605c>] entry_SYSCALL_64_fastpath+0xbf/0xc1

Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Mar 23, 2018
commit 5ee39a7 upstream.

aarch64 unhandled signal kernel messages are very verbose, suggesting
them to be more of a debugging aid:

sigsegv[33]: unhandled level 2 translation fault (11) at 0x00000000, esr
0x92000046, in sigsegv[400000+71000]
CPU: 1 PID: 33 Comm: sigsegv Tainted: G        W        4.15.0-rc3+ #3
Hardware name: linux,dummy-virt (DT)
pstate: 60000000 (nZCv daif -PAN -UAO)
pc : 0x4003f4
lr : 0x4006bc
sp : 0000fffffe94a060
x29: 0000fffffe94a070 x28: 0000000000000000
x27: 0000000000000000 x26: 0000000000000000
x25: 0000000000000000 x24: 00000000004001b0
x23: 0000000000486ac8 x22: 00000000004001c8
x21: 0000000000000000 x20: 0000000000400be8
x19: 0000000000400b30 x18: 0000000000484728
x17: 000000000865ffc8 x16: 000000000000270f
x15: 00000000000000b0 x14: 0000000000000002
x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: 0008000020008008
x9 : 000000000000000f x8 : ffffffffffffffff
x7 : 0004000000000000 x6 : ffffffffffffffff
x5 : 0000000000000000 x4 : 0000000000000000
x3 : 00000000004003e4 x2 : 0000fffffe94a1e8
x1 : 000000000000000a x0 : 0000000000000000

Disable them by default, so they can be enabled using
/proc/sys/debug/exception-trace.

Cc: <stable@vger.kernel.org>
Signed-off-by: Michael Weiser <michael.weiser@gmx.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Mar 23, 2018
[ upstream commit 16338a9 ]

I recently noticed a crash on arm64 when feeding a bogus index
into BPF tail call helper. The crash would not occur when the
interpreter is used, but only in case of JIT. Output looks as
follows:

  [  347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510
  [...]
  [  347.043065] [fffb850e96492510] address between user and kernel address ranges
  [  347.050205] Internal error: Oops: 96000004 [#1] SMP
  [...]
  [  347.190829] x13: 0000000000000000 x12: 0000000000000000
  [  347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10
  [  347.201427] x9 : 0000000000000000 x8 : 0000000000000000
  [  347.206726] x7 : 0000000000000000 x6 : 001c991738000000
  [  347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a
  [  347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500
  [  347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500
  [  347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61)
  [  347.235221] Call trace:
  [  347.237656]  0xffff000002f3a4fc
  [  347.240784]  bpf_test_run+0x78/0xf8
  [  347.244260]  bpf_prog_test_run_skb+0x148/0x230
  [  347.248694]  SyS_bpf+0x77c/0x1110
  [  347.251999]  el0_svc_naked+0x30/0x34
  [  347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b)
  [...]

In this case the index used in BPF r3 is the same as in r1
at the time of the call, meaning we fed a pointer as index;
here, it had the value 0xffff808fd7cf0500 which sits in x2.

While I found tail calls to be working in general (also for
hitting the error cases), I noticed the following in the code
emission:

  # bpftool p d j i 988
  [...]
  38:   ldr     w10, [x1,x10]
  3c:   cmp     w2, w10
  40:   b.ge    0x000000000000007c              <-- signed cmp
  44:   mov     x10, #0x20                      // #32
  48:   cmp     x26, x10
  4c:   b.gt    0x000000000000007c
  50:   add     x26, x26, #0x1
  54:   mov     x10, #0x110                     // Freescale#272
  58:   add     x10, x1, x10
  5c:   lsl     x11, x2, #3
  60:   ldr     x11, [x10,x11]                  <-- faulting insn (f86b694b)
  64:   cbz     x11, 0x000000000000007c
  [...]

Meaning, the tests passed because commit ddb5599 ("arm64:
bpf: implement bpf_tail_call() helper") was using signed compares
instead of unsigned which as a result had the test wrongly passing.

Change this but also the tail call count test both into unsigned
and cap the index as u32. Latter we did as well in 90caccd
("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here,
too. Tested on HiSilicon Hi1616.

Result after patch:

  # bpftool p d j i 268
  [...]
  38:	ldr	w10, [x1,x10]
  3c:	add	w2, w2, #0x0
  40:	cmp	w2, w10
  44:	b.cs	0x0000000000000080
  48:	mov	x10, #0x20                  	// #32
  4c:	cmp	x26, x10
  50:	b.hi	0x0000000000000080
  54:	add	x26, x26, #0x1
  58:	mov	x10, #0x110                 	// Freescale#272
  5c:	add	x10, x1, x10
  60:	lsl	x11, x2, #3
  64:	ldr	x11, [x10,x11]
  68:	cbz	x11, 0x0000000000000080
  [...]

Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Apr 13, 2018
[ Upstream commit 72d5481 ]

It is unlikely request_threaded_irq will fail, but if it does for some
reason we should clear iommu->pr_irq in the error path. Also
intel_svm_finish_prq shouldn't try to clean up the page request
interrupt if pr_irq is 0. Without these, if request_threaded_irq were
to fail the following occurs:

fail with no fixes:

[    0.683147] ------------[ cut here ]------------
[    0.683148] NULL pointer, cannot free irq
[    0.683158] WARNING: CPU: 1 PID: 1 at kernel/irq/irqdomain.c:1632 irq_domain_free_irqs+0x126/0x140
[    0.683160] Modules linked in:
[    0.683163] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2 #3
[    0.683165] Hardware name:                  /NUC7i3BNB, BIOS BNKBL357.86A.0036.2017.0105.1112 01/05/2017
[    0.683168] RIP: 0010:irq_domain_free_irqs+0x126/0x140
[    0.683169] RSP: 0000:ffffc90000037ce8 EFLAGS: 00010292
[    0.683171] RAX: 000000000000001d RBX: ffff880276283c00 RCX: ffffffff81c5e5e8
[    0.683172] RDX: 0000000000000001 RSI: 0000000000000096 RDI: 0000000000000246
[    0.683174] RBP: ffff880276283c00 R08: 0000000000000000 R09: 000000000000023c
[    0.683175] R10: 0000000000000007 R11: 0000000000000000 R12: 000000000000007a
[    0.683176] R13: 0000000000000001 R14: 0000000000000000 R15: 0000010010000000
[    0.683178] FS:  0000000000000000(0000) GS:ffff88027ec80000(0000) knlGS:0000000000000000
[    0.683180] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.683181] CR2: 0000000000000000 CR3: 0000000001c09001 CR4: 00000000003606e0
[    0.683182] Call Trace:
[    0.683189]  intel_svm_finish_prq+0x3c/0x60
[    0.683191]  free_dmar_iommu+0x1ac/0x1b0
[    0.683195]  init_dmars+0xaaa/0xaea
[    0.683200]  ? klist_next+0x19/0xc0
[    0.683203]  ? pci_do_find_bus+0x50/0x50
[    0.683205]  ? pci_get_dev_by_id+0x52/0x70
[    0.683208]  intel_iommu_init+0x498/0x5c7
[    0.683211]  pci_iommu_init+0x13/0x3c
[    0.683214]  ? e820__memblock_setup+0x61/0x61
[    0.683217]  do_one_initcall+0x4d/0x1a0
[    0.683220]  kernel_init_freeable+0x186/0x20e
[    0.683222]  ? set_debug_rodata+0x11/0x11
[    0.683225]  ? rest_init+0xb0/0xb0
[    0.683226]  kernel_init+0xa/0xff
[    0.683229]  ret_from_fork+0x1f/0x30
[    0.683259] Code: 89 ee 44 89 e7 e8 3b e8 ff ff 5b 5d 44 89 e7 44 89 ee 41 5c 41 5d 41 5e e9 a8 84 ff ff 48 c7 c7 a8 71 a7 81 31 c0 e8 6a d3 f9 ff <0f> ff 5b 5d 41 5c 41 5d 41 5
e c3 0f 1f 44 00 00 66 2e 0f 1f 84
[    0.683285] ---[ end trace f7650e42792627ca ]---

with iommu->pr_irq = 0, but no check in intel_svm_finish_prq:

[    0.669561] ------------[ cut here ]------------
[    0.669563] Trying to free already-free IRQ 0
[    0.669573] WARNING: CPU: 3 PID: 1 at kernel/irq/manage.c:1546 __free_irq+0xa4/0x2c0
[    0.669574] Modules linked in:
[    0.669577] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2 #4
[    0.669579] Hardware name:                  /NUC7i3BNB, BIOS BNKBL357.86A.0036.2017.0105.1112 01/05/2017
[    0.669581] RIP: 0010:__free_irq+0xa4/0x2c0
[    0.669582] RSP: 0000:ffffc90000037cc0 EFLAGS: 00010082
[    0.669584] RAX: 0000000000000021 RBX: 0000000000000000 RCX: ffffffff81c5e5e8
[    0.669585] RDX: 0000000000000001 RSI: 0000000000000086 RDI: 0000000000000046
[    0.669587] RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000023c
[    0.669588] R10: 0000000000000007 R11: 0000000000000000 R12: ffff880276253960
[    0.669589] R13: ffff8802762538a4 R14: ffff880276253800 R15: ffff880276283600
[    0.669593] FS:  0000000000000000(0000) GS:ffff88027ed80000(0000) knlGS:0000000000000000
[    0.669594] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.669596] CR2: 0000000000000000 CR3: 0000000001c09001 CR4: 00000000003606e0
[    0.669602] Call Trace:
[    0.669616]  free_irq+0x30/0x60
[    0.669620]  intel_svm_finish_prq+0x34/0x60
[    0.669623]  free_dmar_iommu+0x1ac/0x1b0
[    0.669627]  init_dmars+0xaaa/0xaea
[    0.669631]  ? klist_next+0x19/0xc0
[    0.669634]  ? pci_do_find_bus+0x50/0x50
[    0.669637]  ? pci_get_dev_by_id+0x52/0x70
[    0.669639]  intel_iommu_init+0x498/0x5c7
[    0.669642]  pci_iommu_init+0x13/0x3c
[    0.669645]  ? e820__memblock_setup+0x61/0x61
[    0.669648]  do_one_initcall+0x4d/0x1a0
[    0.669651]  kernel_init_freeable+0x186/0x20e
[    0.669653]  ? set_debug_rodata+0x11/0x11
[    0.669656]  ? rest_init+0xb0/0xb0
[    0.669658]  kernel_init+0xa/0xff
[    0.669661]  ret_from_fork+0x1f/0x30
[    0.669662] Code: 7a 08 75 0e e9 c3 01 00 00 4c 39 7b 08 74 57 48 89 da 48 8b 5a 18 48 85 db 75 ee 89 ee 48 c7 c7 78 67 a7 81 31 c0 e8 4c 37 fa ff <0f> ff 48 8b 34 24 4c 89 ef e
8 0e 4c 68 00 49 8b 46 40 48 8b 80
[    0.669688] ---[ end trace 58a470248700f2fc ]---

Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request May 24, 2018
commit 5c64576 upstream.

syzkaller reports for wrong rtnl_lock usage in sync code [1] and [2]

We have 2 problems in start_sync_thread if error path is
taken, eg. on memory allocation error or failure to configure
sockets for mcast group or addr/port binding:

1. recursive locking: holding rtnl_lock while calling sock_release
which in turn calls again rtnl_lock in ip_mc_drop_socket to leave
the mcast group, as noticed by Florian Westphal. Additionally,
sock_release can not be called while holding sync_mutex (ABBA
deadlock).

2. task hung: holding rtnl_lock while calling kthread_stop to
stop the running kthreads. As the kthreads do the same to leave
the mcast group (sock_release -> ip_mc_drop_socket -> rtnl_lock)
they hang.

Fix the problems by calling rtnl_unlock early in the error path,
now sock_release is called after unlocking both mutexes.

Problem 3 (task hung reported by syzkaller [2]) is variant of
problem 2: use _trylock to prevent one user to call rtnl_lock and
then while waiting for sync_mutex to block kthreads that execute
sock_release when they are stopped by stop_sync_thread.

[1]
IPVS: stopping backup sync thread 4500 ...
WARNING: possible recursive locking detected
4.16.0-rc7+ #3 Not tainted
--------------------------------------------
syzkaller688027/4497 is trying to acquire lock:
  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

but task is already holding lock:
IPVS: stopping backup sync thread 4495 ...
  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

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

        CPU0
        ----
   lock(rtnl_mutex);
   lock(rtnl_mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

2 locks held by syzkaller688027/4497:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
  #1:  (ipvs->sync_mutex){+.+.}, at: [<00000000703f78e3>]
do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388

stack backtrace:
CPU: 1 PID: 4497 Comm: syzkaller688027 Not tainted 4.16.0-rc7+ #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x194/0x24d lib/dump_stack.c:53
  print_deadlock_bug kernel/locking/lockdep.c:1761 [inline]
  check_deadlock kernel/locking/lockdep.c:1805 [inline]
  validate_chain kernel/locking/lockdep.c:2401 [inline]
  __lock_acquire+0xe8f/0x3e00 kernel/locking/lockdep.c:3431
  lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
  __mutex_lock_common kernel/locking/mutex.c:756 [inline]
  __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
  rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
  ip_mc_drop_socket+0x88/0x230 net/ipv4/igmp.c:2643
  inet_release+0x4e/0x1c0 net/ipv4/af_inet.c:413
  sock_release+0x8d/0x1e0 net/socket.c:595
  start_sync_thread+0x2213/0x2b70 net/netfilter/ipvs/ip_vs_sync.c:1924
  do_ip_vs_set_ctl+0x1139/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2389
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1261
  udp_setsockopt+0x45/0x80 net/ipv4/udp.c:2406
  sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975
  SYSC_setsockopt net/socket.c:1849 [inline]
  SyS_setsockopt+0x189/0x360 net/socket.c:1828
  do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x446a69
RSP: 002b:00007fa1c3a64da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446a69
RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006e29fc R08: 0000000000000018 R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 00000000006e29f8
R13: 00676e697279656b R14: 00007fa1c3a659c0 R15: 00000000006e2b60

[2]
IPVS: sync thread started: state = BACKUP, mcast_ifn = syz_tun, syncid = 4,
id = 0
IPVS: stopping backup sync thread 25415 ...
INFO: task syz-executor7:25421 blocked for more than 120 seconds.
       Not tainted 4.16.0-rc6+ Freescale#284
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor7   D23688 25421   4408 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2862 [inline]
  __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440
  schedule+0xf5/0x430 kernel/sched/core.c:3499
  schedule_timeout+0x1a3/0x230 kernel/time/timer.c:1777
  do_wait_for_common kernel/sched/completion.c:86 [inline]
  __wait_for_common kernel/sched/completion.c:107 [inline]
  wait_for_common kernel/sched/completion.c:118 [inline]
  wait_for_completion+0x415/0x770 kernel/sched/completion.c:139
  kthread_stop+0x14a/0x7a0 kernel/kthread.c:530
  stop_sync_thread+0x3d9/0x740 net/netfilter/ipvs/ip_vs_sync.c:1996
  do_ip_vs_set_ctl+0x2b1/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2394
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1253
  sctp_setsockopt+0x2ca/0x63e0 net/sctp/socket.c:4154
  sock_common_setsockopt+0x95/0xd0 net/core/sock.c:3039
  SYSC_setsockopt net/socket.c:1850 [inline]
  SyS_setsockopt+0x189/0x360 net/socket.c:1829
  do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454889
RSP: 002b:00007fc927626c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fc9276276d4 RCX: 0000000000454889
RDX: 000000000000048c RSI: 0000000000000000 RDI: 0000000000000017
RBP: 000000000072bf58 R08: 0000000000000018 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000051c R14: 00000000006f9b40 R15: 0000000000000001

Showing all locks held in the system:
2 locks held by khungtaskd/868:
  #0:  (rcu_read_lock){....}, at: [<00000000a1a8f002>]
check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
  #0:  (rcu_read_lock){....}, at: [<00000000a1a8f002>] watchdog+0x1c5/0xd60
kernel/hung_task.c:249
  #1:  (tasklist_lock){.+.+}, at: [<0000000037c2f8f9>]
debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4247:
  #0:  (&f->f_pos_lock){+.+.}, at: [<000000000d8d6983>]
__fdget_pos+0x12b/0x190 fs/file.c:765
2 locks held by getty/4338:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4339:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4340:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4341:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4342:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4343:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4344:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
3 locks held by kworker/0:5/6494:
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] work_static include/linux/workqueue.h:198 [inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] set_work_data kernel/workqueue.c:619 [inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] set_work_pool_and_clear_pending kernel/workqueue.c:646
[inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084
  #1:  ((addr_chk_work).work){+.+.}, at: [<00000000278427d5>]
process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088
  #2:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
1 lock held by syz-executor7/25421:
  #0:  (ipvs->sync_mutex){+.+.}, at: [<00000000d414a689>]
do_ip_vs_set_ctl+0x277/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2393
2 locks held by syz-executor7/25427:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
  #1:  (ipvs->sync_mutex){+.+.}, at: [<00000000e6d48489>]
do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388
1 lock held by syz-executor7/25435:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
1 lock held by ipvs-b:2:0/25415:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

Reported-and-tested-by: syzbot+a46d6abf9d56b1365a72@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+5fe074c01b2032ce9618@syzkaller.appspotmail.com
Fixes: e0b26cc ("ipvs: call rtnl_lock early")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Zubin Mithra <zsm@chromium.org>
Cc: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request May 24, 2018
…s found

[ Upstream commit 72f17ba ]

If an OVS_ATTR_NESTED attribute type is found while walking
through netlink attributes, we call nlattr_set() recursively
passing the length table for the following nested attributes, if
different from the current one.

However, once we're done with those sub-nested attributes, we
should continue walking through attributes using the current
table, instead of using the one related to the sub-nested
attributes.

For example, given this sequence:

1  OVS_KEY_ATTR_PRIORITY
2  OVS_KEY_ATTR_TUNNEL
3	OVS_TUNNEL_KEY_ATTR_ID
4	OVS_TUNNEL_KEY_ATTR_IPV4_SRC
5	OVS_TUNNEL_KEY_ATTR_IPV4_DST
6	OVS_TUNNEL_KEY_ATTR_TTL
7	OVS_TUNNEL_KEY_ATTR_TP_SRC
8	OVS_TUNNEL_KEY_ATTR_TP_DST
9  OVS_KEY_ATTR_IN_PORT
10 OVS_KEY_ATTR_SKB_MARK
11 OVS_KEY_ATTR_MPLS

we switch to the 'ovs_tunnel_key_lens' table on attribute #3,
and we don't switch back to 'ovs_key_lens' while setting
attributes #9 to #11 in the sequence. As OVS_KEY_ATTR_MPLS
evaluates to 21, and the array size of 'ovs_tunnel_key_lens' is
15, we also get this kind of KASan splat while accessing the
wrong table:

[ 7654.586496] ==================================================================
[ 7654.594573] BUG: KASAN: global-out-of-bounds in nlattr_set+0x164/0xde9 [openvswitch]
[ 7654.603214] Read of size 4 at addr ffffffffc169ecf0 by task handler29/87430
[ 7654.610983]
[ 7654.612644] CPU: 21 PID: 87430 Comm: handler29 Kdump: loaded Not tainted 3.10.0-866.el7.test.x86_64 #1
[ 7654.623030] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016
[ 7654.631379] Call Trace:
[ 7654.634108]  [<ffffffffb65a7c50>] dump_stack+0x19/0x1b
[ 7654.639843]  [<ffffffffb53ff373>] print_address_description+0x33/0x290
[ 7654.647129]  [<ffffffffc169b37b>] ? nlattr_set+0x164/0xde9 [openvswitch]
[ 7654.654607]  [<ffffffffb53ff812>] kasan_report.part.3+0x242/0x330
[ 7654.661406]  [<ffffffffb53ff9b4>] __asan_report_load4_noabort+0x34/0x40
[ 7654.668789]  [<ffffffffc169b37b>] nlattr_set+0x164/0xde9 [openvswitch]
[ 7654.676076]  [<ffffffffc167ef68>] ovs_nla_get_match+0x10c8/0x1900 [openvswitch]
[ 7654.684234]  [<ffffffffb61e9cc8>] ? genl_rcv+0x28/0x40
[ 7654.689968]  [<ffffffffb61e7733>] ? netlink_unicast+0x3f3/0x590
[ 7654.696574]  [<ffffffffc167dea0>] ? ovs_nla_put_tunnel_info+0xb0/0xb0 [openvswitch]
[ 7654.705122]  [<ffffffffb4f41b50>] ? unwind_get_return_address+0xb0/0xb0
[ 7654.712503]  [<ffffffffb65d9355>] ? system_call_fastpath+0x1c/0x21
[ 7654.719401]  [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370
[ 7654.726298]  [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370
[ 7654.733195]  [<ffffffffb53fe4b5>] ? kasan_unpoison_shadow+0x35/0x50
[ 7654.740187]  [<ffffffffb53fe62a>] ? kasan_kmalloc+0xaa/0xe0
[ 7654.746406]  [<ffffffffb53fec32>] ? kasan_slab_alloc+0x12/0x20
[ 7654.752914]  [<ffffffffb53fe711>] ? memset+0x31/0x40
[ 7654.758456]  [<ffffffffc165bf92>] ovs_flow_cmd_new+0x2b2/0xf00 [openvswitch]

[snip]

[ 7655.132484] The buggy address belongs to the variable:
[ 7655.138226]  ovs_tunnel_key_lens+0xf0/0xffffffffffffd400 [openvswitch]
[ 7655.145507]
[ 7655.147166] Memory state around the buggy address:
[ 7655.152514]  ffffffffc169eb80: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
[ 7655.160585]  ffffffffc169ec00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 7655.168644] >ffffffffc169ec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa
[ 7655.176701]                                                              ^
[ 7655.184372]  ffffffffc169ed00: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 05
[ 7655.192431]  ffffffffc169ed80: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
[ 7655.200490] ==================================================================

Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Fixes: 982b527 ("openvswitch: Fix mask generation for nested attributes.")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 3, 2018
[ Upstream commit 2c0aa08 ]

Scenario:
1. Port down and do fail over
2. Ap do rds_bind syscall

PID: 47039  TASK: ffff89887e2fe640  CPU: 47  COMMAND: "kworker/u:6"
 #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9
 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3
 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518
 #3 [ffff898e35f15b60] no_context at ffffffff8104854c
 #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675
 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3
 #6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8
 #7 [ffff898e35f15d10] page_fault at ffffffff8150ea95
    [exception RIP: unknown or invalid address]
    RIP: 0000000000000000  RSP: ffff898e35f15dc8  RFLAGS: 00010282
    RAX: 00000000fffffffe  RBX: ffff889b77f6fc00  RCX:ffffffff81c99d88
    RDX: 0000000000000000  RSI: ffff896019ee08e8  RDI:ffff889b77f6fc00
    RBP: ffff898e35f15df0   R8: ffff896019ee08c8  R9:0000000000000000
    R10: 0000000000000400  R11: 0000000000000000  R12:ffff896019ee08c0
    R13: ffff889b77f6fe68  R14: ffffffff81c99d80  R15: ffffffffa022a1e0
    ORIG_RAX: ffffffffffffffff  CS: 0010 SS: 0018
 #8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm]
 #9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6
 #10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0
 #11 [ffff898e35f15ee8] kthread at ffffffff81090fe6

PID: 45659  TASK: ffff880d313d2500  CPU: 31  COMMAND: "oracle_45659_ap"
 #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4
 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf
 #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7
 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb
 #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm]
 #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma]
 #6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds]
 #7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds]
 #8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670

PID: 45659                          PID: 47039
rds_ib_laddr_check
  /* create id_priv with a null event_handler */
  rdma_create_id
  rdma_bind_addr
    cma_acquire_dev
      /* add id_priv to cma_dev->id_list */
      cma_attach_to_dev
                                    cma_ndev_work_handler
                                      /* event_hanlder is null */
                                      id_priv->id.event_handler

Signed-off-by: Guanglei Li <guanglei.li@oracle.com>
Signed-off-by: Honglei Wang <honglei.wang@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yanjun Zhu <yanjun.zhu@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 3, 2018
[ Upstream commit fca3234 ]

Executing command 'perf stat -T -- ls' dumps core on x86 and s390.

Here is the call back chain (done on x86):

 # gdb ./perf
 ....
 (gdb) r stat -T -- ls
...
Program received signal SIGSEGV, Segmentation fault.
0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6
(gdb) where
 #0  0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6
 #1  0x00007ffff56ae484 in asprintf () from /lib64/libc.so.6
 #2  0x00000000004f1982 in __parse_events_add_pmu (parse_state=0x7fffffffd580,
    list=0xbfb970, name=0xbf3ef0 "cpu",
    head_config=0xbfb930, auto_merge_stats=false) at util/parse-events.c:1233
 #3  0x00000000004f1c8e in parse_events_add_pmu (parse_state=0x7fffffffd580,
    list=0xbfb970, name=0xbf3ef0 "cpu",
    head_config=0xbfb930) at util/parse-events.c:1288
 #4  0x0000000000537ce3 in parse_events_parse (_parse_state=0x7fffffffd580,
    scanner=0xbf4210) at util/parse-events.y:234
 #5  0x00000000004f2c7a in parse_events__scanner (str=0x6b66c0
    "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}",
    parse_state=0x7fffffffd580, start_token=258) at util/parse-events.c:1673
 #6  0x00000000004f2e23 in parse_events (evlist=0xbe9990, str=0x6b66c0
    "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}", err=0x0)
    at util/parse-events.c:1713
 #7  0x000000000044e137 in add_default_attributes () at builtin-stat.c:2281
 #8  0x000000000044f7b5 in cmd_stat (argc=1, argv=0x7fffffffe3b0) at
    builtin-stat.c:2828
 #9  0x00000000004c8b0f in run_builtin (p=0xab01a0 <commands+288>, argc=4,
    argv=0x7fffffffe3b0) at perf.c:297
 #10 0x00000000004c8d7c in handle_internal_command (argc=4,
    argv=0x7fffffffe3b0) at perf.c:349
 #11 0x00000000004c8ece in run_argv (argcp=0x7fffffffe20c,
   argv=0x7fffffffe200) at perf.c:393
 #12 0x00000000004c929c in main (argc=4, argv=0x7fffffffe3b0) at perf.c:537
(gdb)

It turns out that a NULL pointer is referenced. Here are the
function calls:

  ...
  cmd_stat()
  +---> add_default_attributes()
	+---> parse_events(evsel_list, transaction_attrs, NULL);
	             3rd parameter set to NULL

Function parse_events(xx, xx, struct parse_events_error *err) dives
into a bison generated scanner and creates
parser state information for it first:

   struct parse_events_state parse_state = {
                .list   = LIST_HEAD_INIT(parse_state.list),
                .idx    = evlist->nr_entries,
                .error  = err,   <--- NULL POINTER !!!
                .evlist = evlist,
        };

Now various functions inside the bison scanner are called to end up in
__parse_events_add_pmu(struct parse_events_state *parse_state, ..) with
first parameter being a pointer to above structure definition.

Now the PMU event name is not found (because being executed in a VM) and
this function tries to create an error message with

   asprintf(&parse_state->error.str, ....)

which references a NULL pointer and dumps core.

Fix this by providing a pointer to the necessary error information
instead of NULL. Technically only the else part is needed to avoid the
core dump, just lets be safe...

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180308145735.64717-1-tmricht@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 3, 2018
[ Upstream commit 2bbea6e ]

when mounting an ISO filesystem sometimes (very rarely)
the system hangs because of a race condition between two tasks.

PID: 6766   TASK: ffff88007b2a6dd0  CPU: 0   COMMAND: "mount"
 #0 [ffff880078447ae0] __schedule at ffffffff8168d605
 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49
 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995
 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef
 #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod]
 #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50
 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3
 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs]
 #8 [ffff880078447da8] mount_bdev at ffffffff81202570
 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs]
#10 [ffff880078447e28] mount_fs at ffffffff81202d09
#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f
#12 [ffff880078447ea8] do_mount at ffffffff81220fee
#13 [ffff880078447f28] sys_mount at ffffffff812218d6
#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007fd9ea914e9a  RSP: 00007ffd5d9bf648  RFLAGS: 00010246
    RAX: 00000000000000a5  RBX: ffffffff81698c49  RCX: 0000000000000010
    RDX: 00007fd9ec2bc210  RSI: 00007fd9ec2bc290  RDI: 00007fd9ec2bcf30
    RBP: 0000000000000000   R8: 0000000000000000   R9: 0000000000000010
    R10: 00000000c0ed0001  R11: 0000000000000206  R12: 00007fd9ec2bc040
    R13: 00007fd9eb6b2380  R14: 00007fd9ec2bc210  R15: 00007fd9ec2bcf30
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

This task was trying to mount the cdrom.  It allocated and configured a
super_block struct and owned the write-lock for the super_block->s_umount
rwsem. While exclusively owning the s_umount lock, it called
sr_block_ioctl and waited to acquire the global sr_mutex lock.

PID: 6785   TASK: ffff880078720fb0  CPU: 0   COMMAND: "systemd-udevd"
 #0 [ffff880078417898] __schedule at ffffffff8168d605
 #1 [ffff880078417900] schedule at ffffffff8168dc59
 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605
 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838
 #4 [ffff8800784179d0] down_read at ffffffff8168cde0
 #5 [ffff8800784179e8] get_super at ffffffff81201cc7
 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de
 #7 [ffff880078417a40] flush_disk at ffffffff8123a94b
 #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50
 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom]
#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod]
#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86
#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65
#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b
#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7
#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf
#16 [ffff880078417d00] do_last at ffffffff8120d53d
#17 [ffff880078417db0] path_openat at ffffffff8120e6b2
#18 [ffff880078417e48] do_filp_open at ffffffff8121082b
#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33
#20 [ffff880078417f70] sys_open at ffffffff811fde4e
#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49
    RIP: 00007f29438b0c20  RSP: 00007ffc76624b78  RFLAGS: 00010246
    RAX: 0000000000000002  RBX: ffffffff81698c49  RCX: 0000000000000000
    RDX: 00007f2944a5fa70  RSI: 00000000000a0800  RDI: 00007f2944a5fa70
    RBP: 00007f2944a5f540   R8: 0000000000000000   R9: 0000000000000020
    R10: 00007f2943614c40  R11: 0000000000000246  R12: ffffffff811fde4e
    R13: ffff880078417f78  R14: 000000000000000c  R15: 00007f2944a4b010
    ORIG_RAX: 0000000000000002  CS: 0033  SS: 002b

This task tried to open the cdrom device, the sr_block_open function
acquired the global sr_mutex lock. The call to check_disk_change()
then saw an event flag indicating a possible media change and tried
to flush any cached data for the device.
As part of the flush, it tried to acquire the super_block->s_umount
lock associated with the cdrom device.
This was the same super_block as created and locked by the previous task.

The first task acquires the s_umount lock and then the sr_mutex_lock;
the second task acquires the sr_mutex_lock and then the s_umount lock.

This patch fixes the issue by moving check_disk_change() out of
cdrom_open() and let the caller take care of it.

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 3, 2018
[ Upstream commit d546b67 ]

spin_lock/unlock was used instead of spin_un/lock_irq
in a procedure used in process space, on a spinlock
which can be grabbed in an interrupt.

This caused the stack trace below to be displayed (on kernel
4.17.0-rc1 compiled with Lock Debugging enabled):

[  154.661474] WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
[  154.668909] 4.17.0-rc1-rdma_rc_mlx+ #3 Tainted: G          I
[  154.675856] -----------------------------------------------------
[  154.682706] modprobe/10159 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[  154.690254] 00000000f3b0e495 (&(&qp_table->lock)->rlock){+.+.}, at: mlx4_qp_remove+0x20/0x50 [mlx4_core]
[  154.700927]
and this task is already holding:
[  154.707461] 0000000094373b5d (&(&cq->lock)->rlock/1){....}, at: destroy_qp_common+0x111/0x560 [mlx4_ib]
[  154.718028] which would create a new lock dependency:
[  154.723705]  (&(&cq->lock)->rlock/1){....} -> (&(&qp_table->lock)->rlock){+.+.}
[  154.731922]
but this new dependency connects a SOFTIRQ-irq-safe lock:
[  154.740798]  (&(&cq->lock)->rlock){..-.}
[  154.740800]
... which became SOFTIRQ-irq-safe at:
[  154.752163]   _raw_spin_lock_irqsave+0x3e/0x50
[  154.757163]   mlx4_ib_poll_cq+0x36/0x900 [mlx4_ib]
[  154.762554]   ipoib_tx_poll+0x4a/0xf0 [ib_ipoib]
...
to a SOFTIRQ-irq-unsafe lock:
[  154.815603]  (&(&qp_table->lock)->rlock){+.+.}
[  154.815604]
... which became SOFTIRQ-irq-unsafe at:
[  154.827718] ...
[  154.827720]   _raw_spin_lock+0x35/0x50
[  154.833912]   mlx4_qp_lookup+0x1e/0x50 [mlx4_core]
[  154.839302]   mlx4_flow_attach+0x3f/0x3d0 [mlx4_core]

Since mlx4_qp_lookup() is called only in process space, we can
simply replace the spin_un/lock calls with spin_un/lock_irq calls.

Fixes: 6dc06c0 ("net/mlx4: Fix the check in attaching steering rules")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 3, 2018
commit 89da619 upstream.

Kernel panic when with high memory pressure, calltrace looks like,

PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java"
 #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb
 #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942
 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30
 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8
 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46
 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc
 #6 [ffff881ec7ed7838] __node_set at ffffffff81680300
 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f
 #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5
 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8
    [exception RIP: _raw_spin_lock_irqsave+47]
    RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046
    RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8
    RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008
    RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098
    R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000
    R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018

It happens in the pagefault and results in double pagefault
during compacting pages when memory allocation fails.

Analysed the vmcore, the page leads to second pagefault is corrupted
with _mapcount=-256, but private=0.

It's caused by the race between migration and ballooning, and lock
missing in virtballoon_migratepage() of virtio_balloon driver.
This patch fix the bug.

Fixes: e225042 ("virtio_balloon: introduce migration primitives to balloon pages")
Cc: stable@vger.kernel.org
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Huang Chong <huang.chong@zte.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jnettlet pushed a commit that referenced this pull request Sep 4, 2018
As per changes in include/linux/jbd_common.h for avoiding the
bit_spin_locks on RT ("fs: jbd/jbd2: Make state lock and journal
head lock rt safe") we do the same thing here.

We use the non atomic __set_bit and __clear_bit inside the scope of
the lock to preserve the ability of the existing LIST_DEBUG code to
use the zero'th bit in the sanity checks.

As a bit spinlock, we had no lockdep visibility into the usage
of the list head locking.  Now, if we were to implement it as a
standard non-raw spinlock, we would see:

BUG: sleeping function called from invalid context at kernel/rtmutex.c:658
in_atomic(): 1, irqs_disabled(): 0, pid: 122, name: udevd
5 locks held by udevd/122:
 #0:  (&sb->s_type->i_mutex_key#7/1){+.+.+.}, at: [<ffffffff811967e8>] lock_rename+0xe8/0xf0
 #1:  (rename_lock){+.+...}, at: [<ffffffff811a277c>] d_move+0x2c/0x60
 #2:  (&dentry->d_lock){+.+...}, at: [<ffffffff811a0763>] dentry_lock_for_move+0xf3/0x130
 #3:  (&dentry->d_lock/2){+.+...}, at: [<ffffffff811a0734>] dentry_lock_for_move+0xc4/0x130
 #4:  (&dentry->d_lock/3){+.+...}, at: [<ffffffff811a0747>] dentry_lock_for_move+0xd7/0x130
Pid: 122, comm: udevd Not tainted 3.4.47-rt62 #7
Call Trace:
 [<ffffffff810b9624>] __might_sleep+0x134/0x1f0
 [<ffffffff817a24d4>] rt_spin_lock+0x24/0x60
 [<ffffffff811a0c4c>] __d_shrink+0x5c/0xa0
 [<ffffffff811a1b2d>] __d_drop+0x1d/0x40
 [<ffffffff811a24be>] __d_move+0x8e/0x320
 [<ffffffff811a278e>] d_move+0x3e/0x60
 [<ffffffff81199598>] vfs_rename+0x198/0x4c0
 [<ffffffff8119b093>] sys_renameat+0x213/0x240
 [<ffffffff817a2de5>] ? _raw_spin_unlock+0x35/0x60
 [<ffffffff8107781c>] ? do_page_fault+0x1ec/0x4b0
 [<ffffffff817a32ca>] ? retint_swapgs+0xe/0x13
 [<ffffffff813eb0e6>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff8119b0db>] sys_rename+0x1b/0x20
 [<ffffffff817a3b96>] system_call_fastpath+0x1a/0x1f

Since we are only taking the lock during short lived list operations,
lets assume for now that it being raw won't be a significant latency
concern.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
jnettlet pushed a commit that referenced this pull request Sep 4, 2018
| BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:914
| in_atomic(): 1, irqs_disabled(): 0, pid: 255, name: kworker/u257:6
| 5 locks held by kworker/u257:6/255:
|  #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0
|  #1:  ((&entry->work)){+.+.+.}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0
|  #2:  (&shost->scan_mutex){+.+.+.}, at: [<ffffffffa000faa3>] __scsi_add_device+0xa3/0x130 [scsi_mod]
|  #3:  (&set->tag_list_lock){+.+...}, at: [<ffffffff812f09fa>] blk_mq_init_queue+0x96a/0xa50
|  #4:  (rcu_read_lock_sched){......}, at: [<ffffffff8132887d>] percpu_ref_kill_and_confirm+0x1d/0x120
| Preemption disabled at:[<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70
|
| CPU: 2 PID: 255 Comm: kworker/u257:6 Not tainted 3.18.7-rt0+ #1
| Workqueue: events_unbound async_run_entry_fn
|  0000000000000003 ffff8800bc29f998 ffffffff815b3a12 0000000000000000
|  0000000000000000 ffff8800bc29f9b8 ffffffff8109aa16 ffff8800bc29fa28
|  ffff8800bc5d1bc8 ffff8800bc29f9e8 ffffffff815b8dd4 ffff880000000000
| Call Trace:
|  [<ffffffff815b3a12>] dump_stack+0x4f/0x7c
|  [<ffffffff8109aa16>] __might_sleep+0x116/0x190
|  [<ffffffff815b8dd4>] rt_spin_lock+0x24/0x60
|  [<ffffffff810b6089>] __wake_up+0x29/0x60
|  [<ffffffff812ee06e>] blk_mq_usage_counter_release+0x1e/0x20
|  [<ffffffff81328966>] percpu_ref_kill_and_confirm+0x106/0x120
|  [<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70
|  [<ffffffff812f0000>] blk_mq_update_tag_set_depth+0x40/0xd0
|  [<ffffffff812f0a1c>] blk_mq_init_queue+0x98c/0xa50
|  [<ffffffffa000dcf0>] scsi_mq_alloc_queue+0x20/0x60 [scsi_mod]
|  [<ffffffffa000ea35>] scsi_alloc_sdev+0x2f5/0x370 [scsi_mod]
|  [<ffffffffa000f494>] scsi_probe_and_add_lun+0x9e4/0xdd0 [scsi_mod]
|  [<ffffffffa000fb26>] __scsi_add_device+0x126/0x130 [scsi_mod]
|  [<ffffffffa013033f>] ata_scsi_scan_host+0xaf/0x200 [libata]
|  [<ffffffffa012b5b6>] async_port_probe+0x46/0x60 [libata]
|  [<ffffffff810978fb>] async_run_entry_fn+0x3b/0xf0
|  [<ffffffff8108ee81>] process_one_work+0x201/0x5e0

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
jnettlet pushed a commit that referenced this pull request Sep 4, 2018
do_set_cpus_allowed() is not safe vs ->sched_class change.

crash> bt
PID: 11676  TASK: ffff88026f979da0  CPU: 22  COMMAND: "sync_unplug/22"
 #0 [ffff880274d25bc8] machine_kexec at ffffffff8103b41c
 #1 [ffff880274d25c18] crash_kexec at ffffffff810d881a
 #2 [ffff880274d25cd8] oops_end at ffffffff81525818
 #3 [ffff880274d25cf8] do_invalid_op at ffffffff81003096
 #4 [ffff880274d25d90] invalid_op at ffffffff8152d3de
    [exception RIP: set_cpus_allowed_rt+18]
    RIP: ffffffff8109e012  RSP: ffff880274d25e48  RFLAGS: 00010202
    RAX: ffffffff8109e000  RBX: ffff88026f979da0  RCX: ffff8802770cb6e8
    RDX: 0000000000000000  RSI: ffffffff81add700  RDI: ffff88026f979da0
    RBP: ffff880274d25e78   R8: ffffffff816112e0   R9: 0000000000000001
    R10: 0000000000000001  R11: 0000000000011940  R12: ffff88026f979da0
    R13: ffff8802770cb6d0  R14: ffff880274d25fd8  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffff880274d25e60] do_set_cpus_allowed at ffffffff8108e65f
 #6 [ffff880274d25e80] sync_unplug_thread at ffffffff81058c08
 #7 [ffff880274d25ed8] kthread at ffffffff8107cad6
 #8 [ffff880274d25f50] ret_from_fork at ffffffff8152bbbc
crash> task_struct ffff88026f979da0 | grep class
  sched_class = 0xffffffff816111e0 <fair_sched_class+64>,

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
jnettlet pushed a commit that referenced this pull request Sep 4, 2018
…ntext

| BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:914
| in_atomic(): 1, irqs_disabled(): 0, pid: 255, name: kworker/u257:6
| 5 locks held by kworker/u257:6/255:
|  #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0
|  #1:  ((&entry->work)){+.+.+.}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0
|  #2:  (&shost->scan_mutex){+.+.+.}, at: [<ffffffffa000faa3>] __scsi_add_device+0xa3/0x130 [scsi_mod]
|  #3:  (&set->tag_list_lock){+.+...}, at: [<ffffffff812f09fa>] blk_mq_init_queue+0x96a/0xa50
|  #4:  (rcu_read_lock_sched){......}, at: [<ffffffff8132887d>] percpu_ref_kill_and_confirm+0x1d/0x120
| Preemption disabled at:[<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70
|
| CPU: 2 PID: 255 Comm: kworker/u257:6 Not tainted 3.18.7-rt0+ #1
| Workqueue: events_unbound async_run_entry_fn
|  0000000000000003 ffff8800bc29f998 ffffffff815b3a12 0000000000000000
|  0000000000000000 ffff8800bc29f9b8 ffffffff8109aa16 ffff8800bc29fa28
|  ffff8800bc5d1bc8 ffff8800bc29f9e8 ffffffff815b8dd4 ffff880000000000
| Call Trace:
|  [<ffffffff815b3a12>] dump_stack+0x4f/0x7c
|  [<ffffffff8109aa16>] __might_sleep+0x116/0x190
|  [<ffffffff815b8dd4>] rt_spin_lock+0x24/0x60
|  [<ffffffff810b6089>] __wake_up+0x29/0x60
|  [<ffffffff812ee06e>] blk_mq_usage_counter_release+0x1e/0x20
|  [<ffffffff81328966>] percpu_ref_kill_and_confirm+0x106/0x120
|  [<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70
|  [<ffffffff812f0000>] blk_mq_update_tag_set_depth+0x40/0xd0
|  [<ffffffff812f0a1c>] blk_mq_init_queue+0x98c/0xa50
|  [<ffffffffa000dcf0>] scsi_mq_alloc_queue+0x20/0x60 [scsi_mod]
|  [<ffffffffa000ea35>] scsi_alloc_sdev+0x2f5/0x370 [scsi_mod]
|  [<ffffffffa000f494>] scsi_probe_and_add_lun+0x9e4/0xdd0 [scsi_mod]
|  [<ffffffffa000fb26>] __scsi_add_device+0x126/0x130 [scsi_mod]
|  [<ffffffffa013033f>] ata_scsi_scan_host+0xaf/0x200 [libata]
|  [<ffffffffa012b5b6>] async_port_probe+0x46/0x60 [libata]
|  [<ffffffff810978fb>] async_run_entry_fn+0x3b/0xf0
|  [<ffffffff8108ee81>] process_one_work+0x201/0x5e0

percpu_ref_kill_and_confirm() invokes blk_mq_usage_counter_release() in
a rcu-sched region. swait based wake queue can't be used due to
wake_up_all() usage and disabled interrupts in !RT configs (as reported
by Corey Minyard).
The wq_has_sleeper() check has been suggested by Peter Zijlstra.

Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
(cherry picked from commit 2d70105)
Signed-off-by: Julia Cartwright <julia@ni.com>
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