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Florian Westphal and others added 11 commits July 7, 2022 20:55
Kajetan Puchalski reports crash on ARM, with backtrace of:

__nf_ct_delete_from_lists
nf_ct_delete
early_drop
__nf_conntrack_alloc

Unlike atomic_inc_not_zero, refcount_inc_not_zero is not a full barrier.
conntrack uses SLAB_TYPESAFE_BY_RCU, i.e. it is possible that a 'newly'
allocated object is still in use on another CPU:

CPU1						CPU2
						encounter 'ct' during hlist walk
 delete_from_lists
 refcount drops to 0
 kmem_cache_free(ct);
 __nf_conntrack_alloc() // returns same object
						refcount_inc_not_zero(ct); /* might fail */

						/* If set, ct is public/in the hash table */
						test_bit(IPS_CONFIRMED_BIT, &ct->status);

In case CPU1 already set refcount back to 1, refcount_inc_not_zero()
will succeed.

The expected possibilities for a CPU that obtained the object 'ct'
(but no reference so far) are:

1. refcount_inc_not_zero() fails.  CPU2 ignores the object and moves to
   the next entry in the list.  This happens for objects that are about
   to be free'd, that have been free'd, or that have been reallocated
   by __nf_conntrack_alloc(), but where the refcount has not been
   increased back to 1 yet.

2. refcount_inc_not_zero() succeeds. CPU2 checks the CONFIRMED bit
   in ct->status.  If set, the object is public/in the table.

   If not, the object must be skipped; CPU2 calls nf_ct_put() to
   un-do the refcount increment and moves to the next object.

Parallel deletion from the hlists is prevented by a
'test_and_set_bit(IPS_DYING_BIT, &ct->status);' check, i.e. only one
cpu will do the unlink, the other one will only drop its reference count.

Because refcount_inc_not_zero is not a full barrier, CPU2 may try to
delete an object that is not on any list:

1. refcount_inc_not_zero() successful (refcount inited to 1 on other CPU)
2. CONFIRMED test also successful (load was reordered or zeroing
   of ct->status not yet visible)
3. delete_from_lists unlinks entry not on the hlist, because
   IPS_DYING_BIT is 0 (already cleared).

2) is already wrong: CPU2 will handle a partially initited object
that is supposed to be private to CPU1.

Add needed barriers when refcount_inc_not_zero() is successful.

It also inserts a smp_wmb() before the refcount is set to 1 during
allocation.

Because other CPU might still see the object, refcount_set(1)
"resurrects" it, so we need to make sure that other CPUs will also observe
the right content.  In particular, the CONFIRMED bit test must only pass
once the object is fully initialised and either in the hash or about to be
inserted (with locks held to delay possible unlink from early_drop or
gc worker).

I did not change flow_offload_alloc(), as far as I can see it should call
refcount_inc(), not refcount_inc_not_zero(): the ct object is attached to
the skb so its refcount should be >= 1 in all cases.

v2: prefer smp_acquire__after_ctrl_dep to smp_rmb (Will Deacon).
v3: keep smp_acquire__after_ctrl_dep close to refcount_inc_not_zero call
    add comment in nf_conntrack_netlink, no control dependency there
    due to locks.

Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/all/Yr7WTfd6AVTQkLjI@e126311.manchester.arm.com/
Reported-by: Kajetan Puchalski <kajetan.puchalski@arm.com>
Diagnosed-by: Will Deacon <will@kernel.org>
Fixes: 7197743 ("netfilter: conntrack: convert to refcount_t api")
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Will Deacon <will@kernel.org>
NFPROTO_ARP is expecting to find the ARP header at the network offset.

In the particular case of ARP, HTYPE= field shows the initial bytes of
the ethernet header destination MAC address.

 netdev out: IN= OUT=bridge0 MACSRC=c2:76:e5:71:e1:de MACDST=36:b0:4a:e2:72:ea MACPROTO=0806 ARP HTYPE=14000 PTYPE=0x4ae2 OPCODE=49782

NFPROTO_NETDEV egress hook is also expecting to find the IP headers at
the network offset.

Fixes: 35b9395 ("netfilter: add generic ARP packet logger")
Reported-by: Tom Yan <tom.ty89@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
TCP packets will be dropped if the segments number in the tx skb
exceeds limitation when sending iperf3 traffic with --zerocopy option.

we make the following changes:

Get nr_frags in nfp_nfdk_tx_maybe_close_block instead of passing from
outside because it will be changed after skb_linearize operation.

Fill maximum dma_len in first tx descriptor to make sure the whole
head is included in the first descriptor.

Fixes: c10d12e ("nfp: add support for NFDK data path")
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Blamed commit added back a bug I fixed in commit 9bbd917
("vlan: fix memory leak in vlan_dev_set_egress_priority")

If a memory allocation fails in vlan_changelink() after other allocations
succeeded, we need to call vlan_dev_free_egress_priority()
to free all allocated memory because after a failed ->newlink()
we do not call any methods like ndo_uninit() or dev->priv_destructor().

In following example, if the allocation for last element 2000:2001 fails,
we need to free eight prior allocations:

ip link add link dummy0 dummy0.100 type vlan id 100 \
	egress-qos-map 1:2 2:3 3:4 4:5 5:6 6:7 7:8 8:9 2000:2001

syzbot report was:

BUG: memory leak
unreferenced object 0xffff888117bd1060 (size 32):
comm "syz-executor408", pid 3759, jiffies 4294956555 (age 34.090s)
hex dump (first 32 bytes):
09 00 00 00 00 a0 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff83fc60ad>] kmalloc include/linux/slab.h:600 [inline]
[<ffffffff83fc60ad>] vlan_dev_set_egress_priority+0xed/0x170 net/8021q/vlan_dev.c:193
[<ffffffff83fc6628>] vlan_changelink+0x178/0x1d0 net/8021q/vlan_netlink.c:128
[<ffffffff83fc67c8>] vlan_newlink+0x148/0x260 net/8021q/vlan_netlink.c:185
[<ffffffff838b1278>] rtnl_newlink_create net/core/rtnetlink.c:3363 [inline]
[<ffffffff838b1278>] __rtnl_newlink+0xa58/0xdc0 net/core/rtnetlink.c:3580
[<ffffffff838b1629>] rtnl_newlink+0x49/0x70 net/core/rtnetlink.c:3593
[<ffffffff838ac66c>] rtnetlink_rcv_msg+0x21c/0x5c0 net/core/rtnetlink.c:6089
[<ffffffff839f9c37>] netlink_rcv_skb+0x87/0x1d0 net/netlink/af_netlink.c:2501
[<ffffffff839f8da7>] netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
[<ffffffff839f8da7>] netlink_unicast+0x397/0x4c0 net/netlink/af_netlink.c:1345
[<ffffffff839f9266>] netlink_sendmsg+0x396/0x710 net/netlink/af_netlink.c:1921
[<ffffffff8384dbf6>] sock_sendmsg_nosec net/socket.c:714 [inline]
[<ffffffff8384dbf6>] sock_sendmsg+0x56/0x80 net/socket.c:734
[<ffffffff8384e15c>] ____sys_sendmsg+0x36c/0x390 net/socket.c:2488
[<ffffffff838523cb>] ___sys_sendmsg+0x8b/0xd0 net/socket.c:2542
[<ffffffff838525b8>] __sys_sendmsg net/socket.c:2571 [inline]
[<ffffffff838525b8>] __do_sys_sendmsg net/socket.c:2580 [inline]
[<ffffffff838525b8>] __se_sys_sendmsg net/socket.c:2578 [inline]
[<ffffffff838525b8>] __x64_sys_sendmsg+0x78/0xf0 net/socket.c:2578
[<ffffffff845ad8d5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845ad8d5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: 37aa50c ("vlan: introduce vlan_dev_free_egress_priority")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
BUG_ON can be triggered from userspace with an element with a large
userdata area. Replace it by length check and return EINVAL instead.
Over time extensions have been growing in size.

Pick a sufficiently old Fixes: tag to propagate this fix.

Fixes: 7d74026 ("netfilter: nf_tables: variable sized set element keys / data")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
At disconnect time the MPTCP protocol traverse the subflows
list closing each of them. In some circumstances - MPJ subflow,
passive MPTCP socket, the latter operation can remove the
subflow from the list, invalidating the current iterator.

Address the issue using the safe list traversing helper
variant.

Reported-by: van fantasy <g1042620637@gmail.com>
Fixes: b29fcfb ("mptcp: full disconnect implementation")
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new script was not listed in the programs to test.

By consequence, some CIs running MPTCP selftests were not validating
these new tests. Note that MPTCP CI was validating it as it executes all
.sh scripts from 'tools/testing/selftests/net/mptcp' directory.

Fixes: 259a834 ("selftests: mptcp: functional tests for the userspace PM type")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mat Martineau says:

====================
mptcp: Disconnect and selftest fixes

Patch 1 switches to a safe list iterator in the MPTCP disconnect code.

Patch 2 adds the userspace_pm.sh selftest script to the MPTCP selftest
Makefile, resolving the netdev/check_selftest CI failure.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) refcount_inc_not_zero() is not semantically equivalent to
   atomic_int_not_zero(), from Florian Westphal. My understanding was
   that refcount_*() API provides a wrapper to easier debugging of
   reference count leaks, however, there are semantic differences
   between these two APIs, where refcount_inc_not_zero() needs a barrier.
   Reason for this subtle difference to me is unknown.

2) packet logging is not correct for ARP and IP packets, from the
   ARP family and netdev/egress respectively. Use skb_network_offset()
   to reach the headers accordingly.

3) set element extension length have been growing over time, replace
   a BUG_ON by EINVAL which might be triggerable from userspace.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing .gitignore entry.

Fixes: 839b92f ("selftest: tun: add test for NAPI dismantle")
Link: https://lore.kernel.org/r/20220709024141.321683-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add unregister_fib_notifier as rollback of register_fib_notifier.

Fixes: 4394fbc ("net: marvell: prestera: handle fib notifications")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220710122021.7642-1-yevhen.orlov@plvision.eu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
@pchaigno pchaigno force-pushed the ci-test/fix-anysrc-bpf-set-tunnel-key branch 2 times, most recently from b7cc28a to 7b835aa Compare July 13, 2022 09:37
@pchaigno pchaigno closed this Jul 15, 2022
@pchaigno pchaigno deleted the ci-test/fix-anysrc-bpf-set-tunnel-key branch July 15, 2022 17:47
@pchaigno pchaigno restored the ci-test/fix-anysrc-bpf-set-tunnel-key branch July 16, 2022 08:46
@pchaigno pchaigno reopened this Jul 16, 2022
pchaigno added 7 commits July 16, 2022 10:48
This commit extends the ip_tunnel_key struct with a new field for the
flow flags, to pass them to the route lookups. This new field will be
populated and used in subsequent commits.

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Use the new ip_tunnel_key field with the flow flags in the route lookups
for the encapsulated packet. This will be used by the
bpf_skb_set_tunnel_key helper in a subsequent commit.

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Use the new ip_tunnel_key field with the flow flags in the route lookups
for the encapsulated packet. This will be used by the
bpf_skb_set_tunnel_key helper in the subsequent commit.

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Commit 26101f5 ("bpf: Add source ip in "struct bpf_tunnel_key"")
added support for getting and setting the outer source IP of encapsulated
packets via the bpf_skb_{get,set}_tunnel_key BPF helper. This change
allows BPF programs to set any IP address as the source, including for
example the IP address of a container running on the same host.

In that last case, however, the encapsulated packets are dropped when
looking up the route because the source IP address isn't assigned to any
interface on the host. To avoid this, we need to set the
FLOWI_FLAG_ANYSRC flag.

Fixes: 26101f5 ("bpf: Add source ip in "struct bpf_tunnel_key"")
Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Paul Chaignon <paul@isovalent.com>
@pchaigno pchaigno force-pushed the ci-test/fix-anysrc-bpf-set-tunnel-key branch from 7b835aa to 33f709e Compare July 16, 2022 08:48
@pchaigno pchaigno closed this Jul 16, 2022
@pchaigno pchaigno reopened this Jul 16, 2022
@pchaigno pchaigno closed this Jul 16, 2022
@pchaigno pchaigno deleted the ci-test/fix-anysrc-bpf-set-tunnel-key branch July 16, 2022 08:51
pchaigno pushed a commit that referenced this pull request Jul 25, 2022
…tion

Each cset (css_set) is pinned by its tasks. When we're moving tasks around
across csets for a migration, we need to hold the source and destination
csets to ensure that they don't go away while we're moving tasks about. This
is done by linking cset->mg_preload_node on either the
mgctx->preloaded_src_csets or mgctx->preloaded_dst_csets list. Using the
same cset->mg_preload_node for both the src and dst lists was deemed okay as
a cset can't be both the source and destination at the same time.

Unfortunately, this overloading becomes problematic when multiple tasks are
involved in a migration and some of them are identity noop migrations while
others are actually moving across cgroups. For example, this can happen with
the following sequence on cgroup1:

 #1> mkdir -p /sys/fs/cgroup/misc/a/b
 #2> echo $$ > /sys/fs/cgroup/misc/a/cgroup.procs
 #3> RUN_A_COMMAND_WHICH_CREATES_MULTIPLE_THREADS &
 #4> PID=$!
 #5> echo $PID > /sys/fs/cgroup/misc/a/b/tasks
 #6> echo $PID > /sys/fs/cgroup/misc/a/cgroup.procs

the process including the group leader back into a. In this final migration,
non-leader threads would be doing identity migration while the group leader
is doing an actual one.

After #3, let's say the whole process was in cset A, and that after #4, the
leader moves to cset B. Then, during #6, the following happens:

 1. cgroup_migrate_add_src() is called on B for the leader.

 2. cgroup_migrate_add_src() is called on A for the other threads.

 3. cgroup_migrate_prepare_dst() is called. It scans the src list.

 4. It notices that B wants to migrate to A, so it tries to A to the dst
    list but realizes that its ->mg_preload_node is already busy.

 5. and then it notices A wants to migrate to A as it's an identity
    migration, it culls it by list_del_init()'ing its ->mg_preload_node and
    putting references accordingly.

 6. The rest of migration takes place with B on the src list but nothing on
    the dst list.

This means that A isn't held while migration is in progress. If all tasks
leave A before the migration finishes and the incoming task pins it, the
cset will be destroyed leading to use-after-free.

This is caused by overloading cset->mg_preload_node for both src and dst
preload lists. We wanted to exclude the cset from the src list but ended up
inadvertently excluding it from the dst list too.

This patch fixes the issue by separating out cset->mg_preload_node into
->mg_src_preload_node and ->mg_dst_preload_node, so that the src and dst
preloadings don't interfere with each other.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Mukesh Ojha <quic_mojha@quicinc.com>
Reported-by: shisiyuan <shisiyuan19870131@gmail.com>
Link: http://lkml.kernel.org/r/1654187688-27411-1-git-send-email-shisiyuan@xiaomi.com
Link: https://www.spinics.net/lists/cgroups/msg33313.html
Fixes: f817de9 ("cgroup: prepare migration path for unified hierarchy")
Cc: stable@vger.kernel.org # v3.16+
borkmann pushed a commit that referenced this pull request Sep 24, 2023
To plug these leaks detected with:

  $ make EXTRA_CFLAGS="-fsanitize=address" BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin

  =================================================================
  ==473890==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 112 byte(s) in 1 object(s) allocated from:
    #0 0x7fdf19aba097 in calloc (/lib64/libasan.so.8+0xba097)
    #1 0x987836 in zalloc (/home/acme/bin/perf+0x987836)
    #2 0x5367ae in thread_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:1289
    #3 0x5367ae in thread__trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:1307
    #4 0x5367ae in trace__sys_exit /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:2468
    #5 0x52bf34 in trace__handle_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3177
    #6 0x52bf34 in __trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3685
    #7 0x542927 in trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3712
    #8 0x542927 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:4055
    #9 0x542927 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5141
    #10 0x5ef1a2 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
    #11 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
    #12 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
    torvalds#13 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
    torvalds#14 0x7fdf18a4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Direct leak of 2048 byte(s) in 1 object(s) allocated from:
    #0 0x7f788fcba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
    #1 0x5337c0 in trace__sys_enter /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:2342
    #2 0x52bfb4 in trace__handle_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3191
    #3 0x52bfb4 in __trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3699
    #4 0x542883 in trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3726
    #5 0x542883 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:4069
    #6 0x542883 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5155
    #7 0x5ef232 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
    #8 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
    #9 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
    #10 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
    #11 0x7f788ec4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Indirect leak of 48 byte(s) in 1 object(s) allocated from:
    #0 0x7fdf19aba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
    #1 0x77b335 in intlist__new util/intlist.c:116
    #2 0x5367fd in thread_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:1293
    #3 0x5367fd in thread__trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:1307
    #4 0x5367fd in trace__sys_exit /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:2468
    #5 0x52bf34 in trace__handle_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3177
    #6 0x52bf34 in __trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3685
    #7 0x542927 in trace__deliver_event /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3712
    #8 0x542927 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:4055
    #9 0x542927 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5141
    #10 0x5ef1a2 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
    #11 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
    #12 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
    torvalds#13 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
    torvalds#14 0x7fdf18a4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/20230719202951.534582-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 24, 2023
In 3cb4d5e ("perf trace: Free syscall tp fields in
evsel->priv") it only was freeing if strcmp(evsel->tp_format->system,
"syscalls") returned zero, while the corresponding initialization of
evsel->priv was being performed if it was _not_ zero, i.e. if the tp
system wasn't 'syscalls'.

Just stop looking for that and free it if evsel->priv was set, which
should be equivalent.

Also use the pre-existing evsel_trace__delete() function.

This resolves these leaks, detected with:

  $ make EXTRA_CFLAGS="-fsanitize=address" BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin

  =================================================================
  ==481565==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540e8b in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3212
      #7 0x540e8b in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540e8b in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      torvalds#13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540dd1 in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3205
      #7 0x540dd1 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540dd1 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      torvalds#13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  SUMMARY: AddressSanitizer: 80 byte(s) leaked in 2 allocation(s).
  [root@quaco ~]#

With this we plug all leaks with "perf trace sleep 1".

Fixes: 3cb4d5e ("perf trace: Free syscall tp fields in evsel->priv")
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: https://lore.kernel.org/lkml/20230719202951.534582-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 24, 2023
…failure to add a probe

Building perf with EXTRA_CFLAGS="-fsanitize=address" a leak is detect
when trying to add a probe to a non-existent function:

  # perf probe -x ~/bin/perf dso__neW
  Probe point 'dso__neW' not found.
    Error: Failed to add events.

  =================================================================
  ==296634==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 128 byte(s) in 1 object(s) allocated from:
      #0 0x7f67642ba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x7f67641a76f1 in allocate_cfi (/lib64/libdw.so.1+0x3f6f1)

  Direct leak of 65 byte(s) in 1 object(s) allocated from:
      #0 0x7f67642b95b5 in __interceptor_realloc.part.0 (/lib64/libasan.so.8+0xb95b5)
      #1 0x6cac75 in strbuf_grow util/strbuf.c:64
      #2 0x6ca934 in strbuf_init util/strbuf.c:25
      #3 0x9337d2 in synthesize_perf_probe_point util/probe-event.c:2018
      #4 0x92be51 in try_to_find_probe_trace_events util/probe-event.c:964
      #5 0x93d5c6 in convert_to_probe_trace_events util/probe-event.c:3512
      #6 0x93d6d5 in convert_perf_probe_events util/probe-event.c:3529
      #7 0x56f37f in perf_add_probe_events /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:354
      #8 0x572fbc in __cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:738
      #9 0x5730f2 in cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:766
      #10 0x635d81 in run_builtin /var/home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #11 0x6362c1 in handle_internal_command /var/home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #12 0x63667a in run_argv /var/home/acme/git/perf-tools-next/tools/perf/perf.c:421
      torvalds#13 0x636b8d in main /var/home/acme/git/perf-tools-next/tools/perf/perf.c:537
      torvalds#14 0x7f676302950f in __libc_start_call_main (/lib64/libc.so.6+0x2950f)

  SUMMARY: AddressSanitizer: 193 byte(s) leaked in 2 allocation(s).
  #

synthesize_perf_probe_point() returns a "detachec" strbuf, i.e. a
malloc'ed string that needs to be free'd.

An audit will be performed to find other such cases.

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZM0l1Oxamr4SVjfY@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 24, 2023
While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

The same problem was found in 'perf top' after an audit of all
perf_session__new() failure handling.

Fixes: 6ef81c5 ("perf session: Return error code for perf_session__new() function on failure")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Nageswara R Sastry <rnsastry@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Shawn Landden <shawn@git.icu>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lore.kernel.org/lkml/ZN4Q2rxxsL08A8rd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 24, 2023
While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

Fixes: eef4fee ("perf lock: Dynamically allocate lockhash_table")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Ross Zwisler <zwisler@chromium.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/lkml/ZN4R1AYfsD2J8lRs@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 24, 2023
Except for initial reference, mddev->kobject is referenced by
rdev->kobject, and if the last rdev is freed, there is no guarantee that
mddev is still valid. Hence mddev should not be used anymore after
export_rdev().

This problem can be triggered by following test for mdadm at very
low rate:

New file: mdadm/tests/23rdev-lifetime

devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2

clean_up_test() {
        pill -9 $pid
        echo clear > /sys/block/md0/md/array_state
}

trap 'clean_up_test' EXIT

add_by_sysfs() {
        while true; do
                echo $devt > /sys/block/md0/md/new_dev
        done
}

remove_by_sysfs(){
        while true; do
                echo remove > /sys/block/md0/md/dev-${devname}/state
        done
}

echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"

add_by_sysfs &
pid="$pid $!"

remove_by_sysfs &
pid="$pid $!"

sleep $runtime
exit 0

Test cmd:

./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime

Test result:

general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bcb: 0000 [#4] PREEMPT SMP
CPU: 0 PID: 1292 Comm: test Tainted: G      D W          6.5.0-rc2-00121-g01e55c376936 torvalds#562
RIP: 0010:md_wakeup_thread+0x9e/0x320 [md_mod]
Call Trace:
 <TASK>
 mddev_unlock+0x1b6/0x310 [md_mod]
 rdev_attr_store+0xec/0x190 [md_mod]
 sysfs_kf_write+0x52/0x70
 kernfs_fop_write_iter+0x19a/0x2a0
 vfs_write+0x3b5/0x770
 ksys_write+0x74/0x150
 __x64_sys_write+0x22/0x30
 do_syscall_64+0x40/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fix this problem by don't dereference mddev after export_rdev().

Fixes: 3ce94ce ("md: fix duplicate filename for rdev")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825025532.1523008-2-yukuai1@huaweicloud.com
borkmann pushed a commit that referenced this pull request Sep 24, 2023
Jiri Pirko says:

====================
expose devlink instances relationships

From: Jiri Pirko <jiri@nvidia.com>

Currently, the user can instantiate new SF using "devlink port add"
command. That creates an E-switch representor devlink port.

When user activates this SF, there is an auxiliary device created and
probed for it which leads to SF devlink instance creation.

There is 1:1 relationship between E-switch representor devlink port and
the SF auxiliary device devlink instance.

Also, for example in mlx5, one devlink instance is created for
PCI device and one is created for an auxiliary device that represents
the uplink port. The relation between these is invisible to the user.

Patches #1-#3 and #5 are small preparations.

Patch #4 adds netnsid attribute for nested devlink if that in a
different namespace.

Patch #5 is the main one in this set, introduces the relationship
tracking infrastructure later on used to track SFs, linecards and
devlink instance relationships with nested devlink instances.

Expose the relation to the user by introducing new netlink attribute
DEVLINK_PORT_FN_ATTR_DEVLINK which contains the devlink instance related
to devlink port function. This is done by patch #8.
Patch #9 implements this in mlx5 driver.

Patch #10 converts the linecard nested devlink handling to the newly
introduced rel infrastructure.

Patch #11 benefits from the rel infra and introduces possiblitily to
have relation between devlink instances.
Patch #12 implements this in mlx5 driver.

Examples:
$ devlink dev
pci/0000:08:00.0: nested_devlink auxiliary/mlx5_core.eth.0
pci/0000:08:00.1: nested_devlink auxiliary/mlx5_core.eth.1
auxiliary/mlx5_core.eth.1
auxiliary/mlx5_core.eth.0

$ devlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 106
pci/0000:08:00.0/32768: type eth netdev eth4 flavour pcisf controller 0 pfnum 0 sfnum 106 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
$ devlink port function set pci/0000:08:00.0/32768 state active
$ devlink port show pci/0000:08:00.0/32768
pci/0000:08:00.0/32768: type eth netdev eth4 flavour pcisf controller 0 pfnum 0 sfnum 106 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state active opstate attached roce enable nested_devlink auxiliary/mlx5_core.sf.2

$ devlink port show pci/0000:08:00.0/32768
pci/0000:08:00.0/32768: type eth netdev eth4 flavour pcisf controller 0 pfnum 0 sfnum 106 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state active opstate attached roce enable nested_devlink auxiliary/mlx5_core.sf.2 nested_devlink_netns ns1
====================

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
borkmann pushed a commit that referenced this pull request Oct 6, 2023
Fix an error detected by memory sanitizer:
```
==4033==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6
    #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2
    #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9
    #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32
    #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6
    #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8
    #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8
    #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9
    #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8
    #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15
    #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9
    #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8
    #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5
    torvalds#13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9
    torvalds#14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11
    torvalds#15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8
    torvalds#16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2
    torvalds#17 0x55fb0f941dab in main tools/perf/perf.c:535:3
```

Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230914022425.1489035-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
borkmann pushed a commit that referenced this pull request Oct 6, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

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

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
borkmann pushed a commit that referenced this pull request Oct 6, 2023
Petr Machata says:

====================
mlxsw: Provide enhancements and new feature

Vadim Pasternak writes:

Patch #1 - Optimize transaction size for efficient retrieval of module
           data.
Patch #3 - Enable thermal zone binding with new cooling device.
Patch #4 - Employ standard macros for dividing buffer into the chunks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
borkmann pushed a commit that referenced this pull request Oct 17, 2023
Fix the deadlock by refactoring the MR cache cleanup flow to flush the
workqueue without holding the rb_lock.
This adds a race between cache cleanup and creation of new entries which
we solve by denied creation of new entries after cache cleanup started.

Lockdep:
WARNING: possible circular locking dependency detected
 [ 2785.326074 ] 6.2.0-rc6_for_upstream_debug_2023_01_31_14_02 #1 Not tainted
 [ 2785.339778 ] ------------------------------------------------------
 [ 2785.340848 ] devlink/53872 is trying to acquire lock:
 [ 2785.341701 ] ffff888124f8c0c8 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0xc8/0x900
 [ 2785.343403 ]
 [ 2785.343403 ] but task is already holding lock:
 [ 2785.344464 ] ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib]
 [ 2785.346273 ]
 [ 2785.346273 ] which lock already depends on the new lock.
 [ 2785.346273 ]
 [ 2785.347720 ]
 [ 2785.347720 ] the existing dependency chain (in reverse order) is:
 [ 2785.349003 ]
 [ 2785.349003 ] -> #1 (&dev->cache.rb_lock){+.+.}-{3:3}:
 [ 2785.350160 ]        __mutex_lock+0x14c/0x15c0
 [ 2785.350962 ]        delayed_cache_work_func+0x2d1/0x610 [mlx5_ib]
 [ 2785.352044 ]        process_one_work+0x7c2/0x1310
 [ 2785.352879 ]        worker_thread+0x59d/0xec0
 [ 2785.353636 ]        kthread+0x28f/0x330
 [ 2785.354370 ]        ret_from_fork+0x1f/0x30
 [ 2785.355135 ]
 [ 2785.355135 ] -> #0 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}:
 [ 2785.356515 ]        __lock_acquire+0x2d8a/0x5fe0
 [ 2785.357349 ]        lock_acquire+0x1c1/0x540
 [ 2785.358121 ]        __flush_work+0xe8/0x900
 [ 2785.358852 ]        __cancel_work_timer+0x2c7/0x3f0
 [ 2785.359711 ]        mlx5_mkey_cache_cleanup+0xfb/0x250 [mlx5_ib]
 [ 2785.360781 ]        mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x16/0x30 [mlx5_ib]
 [ 2785.361969 ]        __mlx5_ib_remove+0x68/0x120 [mlx5_ib]
 [ 2785.362960 ]        mlx5r_remove+0x63/0x80 [mlx5_ib]
 [ 2785.363870 ]        auxiliary_bus_remove+0x52/0x70
 [ 2785.364715 ]        device_release_driver_internal+0x3c1/0x600
 [ 2785.365695 ]        bus_remove_device+0x2a5/0x560
 [ 2785.366525 ]        device_del+0x492/0xb80
 [ 2785.367276 ]        mlx5_detach_device+0x1a9/0x360 [mlx5_core]
 [ 2785.368615 ]        mlx5_unload_one_devl_locked+0x5a/0x110 [mlx5_core]
 [ 2785.369934 ]        mlx5_devlink_reload_down+0x292/0x580 [mlx5_core]
 [ 2785.371292 ]        devlink_reload+0x439/0x590
 [ 2785.372075 ]        devlink_nl_cmd_reload+0xaef/0xff0
 [ 2785.372973 ]        genl_family_rcv_msg_doit.isra.0+0x1bd/0x290
 [ 2785.374011 ]        genl_rcv_msg+0x3ca/0x6c0
 [ 2785.374798 ]        netlink_rcv_skb+0x12c/0x360
 [ 2785.375612 ]        genl_rcv+0x24/0x40
 [ 2785.376295 ]        netlink_unicast+0x438/0x710
 [ 2785.377121 ]        netlink_sendmsg+0x7a1/0xca0
 [ 2785.377926 ]        sock_sendmsg+0xc5/0x190
 [ 2785.378668 ]        __sys_sendto+0x1bc/0x290
 [ 2785.379440 ]        __x64_sys_sendto+0xdc/0x1b0
 [ 2785.380255 ]        do_syscall_64+0x3d/0x90
 [ 2785.381031 ]        entry_SYSCALL_64_after_hwframe+0x46/0xb0
 [ 2785.381967 ]
 [ 2785.381967 ] other info that might help us debug this:
 [ 2785.381967 ]
 [ 2785.383448 ]  Possible unsafe locking scenario:
 [ 2785.383448 ]
 [ 2785.384544 ]        CPU0                    CPU1
 [ 2785.385383 ]        ----                    ----
 [ 2785.386193 ]   lock(&dev->cache.rb_lock);
 [ 2785.386940 ]				lock((work_completion)(&(&ent->dwork)->work));
 [ 2785.388327 ]				lock(&dev->cache.rb_lock);
 [ 2785.389425 ]   lock((work_completion)(&(&ent->dwork)->work));
 [ 2785.390414 ]
 [ 2785.390414 ]  *** DEADLOCK ***
 [ 2785.390414 ]
 [ 2785.391579 ] 6 locks held by devlink/53872:
 [ 2785.392341 ]  #0: ffffffff84c17a50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40
 [ 2785.393630 ]  #1: ffff888142280218 (&devlink->lock_key){+.+.}-{3:3}, at: devlink_get_from_attrs_lock+0x12d/0x2d0
 [ 2785.395324 ]  #2: ffff8881422d3c38 (&dev->lock_key){+.+.}-{3:3}, at: mlx5_unload_one_devl_locked+0x4a/0x110 [mlx5_core]
 [ 2785.397322 ]  #3: ffffffffa0e59068 (mlx5_intf_mutex){+.+.}-{3:3}, at: mlx5_detach_device+0x60/0x360 [mlx5_core]
 [ 2785.399231 ]  #4: ffff88810e3cb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x8d/0x600
 [ 2785.400864 ]  #5: ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib]

Fixes: b958451 ("RDMA/mlx5: Change the cache structure to an RB-tree")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Michael Guralnik <michaelgur@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
borkmann pushed a commit that referenced this pull request Oct 17, 2023
Petr Machata says:

====================
mlxsw: Control the order of blocks in ACL region

Amit Cohen writes:

For 12 key blocks in the A-TCAM, rules are split into two records, which
constitute two lookups. The two records are linked using a
"large entry key ID".

Due to a Spectrum-4 hardware issue, KVD entries that correspond to key
blocks 0 to 5 of 12 key blocks will be placed in the same KVD pipe if they
only differ in their "large entry key ID", as it is ignored. This results
in a reduced scale, we can insert less than 20k filters and get an error:

    $ tc -b flower.batch
    RTNETLINK answers: Input/output error
    We have an error talking to the kernel

To reduce the probability of this issue, we can place key blocks with
high entropy in blocks 0 to 5. The idea is to place blocks that are often
changed in blocks 0 to 5, for example, key blocks that match on IPv4
addresses or the LSBs of IPv6 addresses. Such placement will reduce the
probability of these blocks to be same.

Mark several blocks with 'high_entropy' flag and place them in blocks 0
to 5. Note that the list of the blocks is just a suggestion, I will verify
it with architects.

Currently, there is a one loop that chooses which blocks should be used
for a given list of elements and fills the blocks - when a block is
chosen, it fills it in the region. To be able to control the order of
the blocks, separate between searching blocks and filling them. Several
pre-changes are required.

Patch set overview:
Patch #1 marks several blocks with 'high_entropy' flag.
Patches #2-#4 prepare the code for filling blocks at the end of the search.
Patch #5 changes the loop to just choose the blocks and fill the blocks at
the end.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
borkmann pushed a commit that referenced this pull request Oct 17, 2023
Amit Cohen says:

====================
Extend VXLAN driver to support FDB flushing

The merge commit 9271686 ("Merge branch 'br-flush-filtering'") added
support for FDB flushing in bridge driver. Extend VXLAN driver to support
FDB flushing also. Add support for filtering by fields which are relevant
for VXLAN FDBs:
* Source VNI
* Nexthop ID
* 'router' flag
* Destination VNI
* Destination Port
* Destination IP

Without this set, flush for VXLAN device fails:
$ bridge fdb flush dev vx10
RTNETLINK answers: Operation not supported

With this set, such flush works with the relevant arguments, for example:
$ bridge fdb flush dev vx10 vni 5000 dst 193.2.2.1
< flush all vx10 entries with VNI 5000 and destination IP 193.2.2.1>

Some preparations are required, handle them before adding flushing support
in VXLAN driver. See more details in commit messages.

Patch set overview:
Patch #1 prepares flush policy to be used by VXLAN driver
Patches #2-#3 are preparations in VXLAN driver
Patch #4 adds an initial support for flushing in VXLAN driver
Patches #5-#9 add support for filtering by several attributes
Patch #10 adds a test for FDB flush with VXLAN
Patch #11 extends the test to check FDB flush with bridge
====================

Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
borkmann added a commit that referenced this pull request Oct 17, 2023
Andrii Nakryiko says:

====================
This patch set fixes ambiguity in BPF verifier log output of SCALAR register
in the parts that emit umin/umax, smin/smax, etc ranges. See patch #4 for
details.

Also, patch #5 fixes an issue with verifier log missing instruction context
(state) output for conditionals that trigger precision marking. See details in
the patch.

First two patches are just improvements to two selftests that are very flaky
locally when run in parallel mode.

Patch #3 changes 'align' selftest to be less strict about exact verifier log
output (which patch #4 changes, breaking lots of align tests as written). Now
test does more of a register substate checks, mostly around expected var_off()
values. This 'align' selftests is one of the more brittle ones and requires
constant adjustment when verifier log output changes, without really catching
any new issues. So hopefully these changes can minimize future support efforts
for this specific set of tests.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
borkmann pushed a commit that referenced this pull request Oct 20, 2023
Chuyi Zhou says:

====================
Add Open-coded task, css_task and css iters

This is version 6 of task, css_task and css iters support.

--- Changelog ---

v5 -> v6:

Patch #3:
 * In bpf_iter_task_next, return pos rather than goto out. (Andrii)
Patch #2, #3, #4:
 * Add the missing __diag_ignore_all to avoid kernel build warning
Patch #5, #6, #7:
 * Add Andrii's ack

Patch #8:
 * In BPF prog iter_css_task_for_each, return -EPERM rather than 0, and
   ensure stack_mprotect() in iters.c not success. If not, it would cause
   the subsequent 'test_lsm' fail, since the 'is_stack' check in
   test_int_hook(lsm.c) would not be guaranteed.
   (https://github.com/kernel-patches/bpf/actions/runs/6489662214/job/17624665086?pr=5790)

v4 -> v5:https://lore.kernel.org/lkml/20231007124522.34834-1-zhouchuyi@bytedance.com/

Patch 3~4:
 * Relax the BUILD_BUG_ON check in bpf_iter_task_new and bpf_iter_css_new to avoid
   netdev/build_32bit CI error.
   (https://netdev.bots.linux.dev/static/nipa/790929/13412333/build_32bit/stderr)
Patch 8:
 * Initialize skel pointer to fix the LLVM-16 build CI error
   (https://github.com/kernel-patches/bpf/actions/runs/6462875618/job/17545170863)

v3 -> v4:https://lore.kernel.org/all/20230925105552.817513-1-zhouchuyi@bytedance.com/

* Address all the comments from Andrii in patch-3 ~ patch-6
* Collect Tejun's ack
* Add a extra patch to rename bpf_iter_task.c to bpf_iter_tasks.c
* Seperate three BPF program files for selftests (iters_task.c iters_css_task.c iters_css.c)

v2 -> v3:https://lore.kernel.org/lkml/20230912070149.969939-1-zhouchuyi@bytedance.com/

Patch 1 (cgroup: Prepare for using css_task_iter_*() in BPF)
  * Add tj's ack and Alexei's suggest-by.
Patch 2 (bpf: Introduce css_task open-coded iterator kfuncs)
  * Use bpf_mem_alloc/bpf_mem_free rather than kzalloc()
  * Add KF_TRUSTED_ARGS for bpf_iter_css_task_new (Alexei)
  * Move bpf_iter_css_task's definition from uapi/linux/bpf.h to
    kernel/bpf/task_iter.c and we can use it from vmlinux.h
  * Move bpf_iter_css_task_XXX's declaration from bpf_helpers.h to
    bpf_experimental.h
Patch 3 (Introduce task open coded iterator kfuncs)
  * Change th API design keep consistent with SEC("iter/task"), support
    iterating all threads(BPF_TASK_ITERATE_ALL) and threads of a
    specific task (BPF_TASK_ITERATE_THREAD).(Andrii)
  * Move bpf_iter_task's definition from uapi/linux/bpf.h to
    kernel/bpf/task_iter.c and we can use it from vmlinux.h
  * Move bpf_iter_task_XXX's declaration from bpf_helpers.h to
    bpf_experimental.h
Patch 4 (Introduce css open-coded iterator kfuncs)
  * Change th API design keep consistent with cgroup_iters, reuse
    BPF_CGROUP_ITER_DESCENDANTS_PRE/BPF_CGROUP_ITER_DESCENDANTS_POST
    /BPF_CGROUP_ITER_ANCESTORS_UP(Andrii)
  * Add KF_TRUSTED_ARGS for bpf_iter_css_new
  * Move bpf_iter_css's definition from uapi/linux/bpf.h to
    kernel/bpf/task_iter.c and we can use it from vmlinux.h
  * Move bpf_iter_css_XXX's declaration from bpf_helpers.h to
    bpf_experimental.h
Patch 5 (teach the verifier to enforce css_iter and task_iter in RCU CS)
  * Add KF flag KF_RCU_PROTECTED to maintain kfuncs which need RCU CS.(Andrii)
  * Consider STACK_ITER when using bpf_for_each_spilled_reg.
Patch 6 (Let bpf_iter_task_new accept null task ptr)
  * Add this extra patch to let bpf_iter_task_new accept a 'nullable'
  * task pointer(Andrii)
Patch 7 (selftests/bpf: Add tests for open-coded task and css iter)
  * Add failure testcase(Alexei)

Changes from v1(https://lore.kernel.org/lkml/20230827072057.1591929-1-zhouchuyi@bytedance.com/):
- Add a pre-patch to make some preparations before supporting css_task
  iters.(Alexei)
- Add an allowlist for css_task iters(Alexei)
- Let bpf progs do explicit bpf_rcu_read_lock() when using process
  iters and css_descendant iters.(Alexei)
---------------------

In some BPF usage scenarios, it will be useful to iterate the process and
css directly in the BPF program. One of the expected scenarios is
customizable OOM victim selection via BPF[1].

Inspired by Dave's task_vma iter[2], this patchset adds three types of
open-coded iterator kfuncs:

1. bpf_task_iters. It can be used to
1) iterate all process in the system, like for_each_forcess() in kernel.
2) iterate all threads in the system.
3) iterate all threads of a specific task

2. bpf_css_iters. It works like css_task_iter_{start, next, end} and would
be used to iterating tasks/threads under a css.

3. css_iters. It works like css_next_descendant_{pre, post} to iterating all
descendant css.

BPF programs can use these kfuncs directly or through bpf_for_each macro.

link[1]: https://lore.kernel.org/lkml/20230810081319.65668-1-zhouchuyi@bytedance.com/
link[2]: https://lore.kernel.org/all/20230810183513.684836-1-davemarchevsky@fb.com/
====================

Link: https://lore.kernel.org/r/20231018061746.111364-1-zhouchuyi@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
borkmann pushed a commit that referenced this pull request Oct 23, 2023
Hou Tao says:

====================
bpf: Fixes for per-cpu kptr

From: Hou Tao <houtao1@huawei.com>

Hi,

The patchset aims to fix the problems found in the review of per-cpu
kptr patch-set [0]. Patch #1 moves pcpu_lock after the invocation of
pcpu_chunk_addr_search() and it is a micro-optimization for
free_percpu(). The reason includes it in the patch is that the same
logic is used in newly-added API pcpu_alloc_size(). Patch #2 introduces
pcpu_alloc_size() for dynamic per-cpu area. Patch #2 and #3 use
pcpu_alloc_size() to check whether or not unit_size matches with the
size of underlying per-cpu area and to select a matching bpf_mem_cache.
Patch #4 fixes the freeing of per-cpu kptr when these kptrs are freed by
map destruction. The last patch adds test cases for these problems.

Please see individual patches for details. And comments are always
welcome.

Change Log:
v3:
 * rebased on bpf-next
 * patch 2: update API document to note that pcpu_alloc_size() doesn't
            support statically allocated per-cpu area. (Dennis)
 * patch 1 & 2: add Acked-by from Dennis

v2: https://lore.kernel.org/bpf/20231018113343.2446300-1-houtao@huaweicloud.com/
  * add a new patch "don't acquire pcpu_lock for pcpu_chunk_addr_search()"
  * patch 2: change type of bit_off and end to unsigned long (Andrew)
  * patch 2: rename the new API as pcpu_alloc_size and follow 80-column convention (Dennis)
  * patch 5: move the common declaration into bpf.h (Stanislav, Alxei)

v1: https://lore.kernel.org/bpf/20231007135106.3031284-1-houtao@huaweicloud.com/

[0]: https://lore.kernel.org/bpf/20230827152729.1995219-1-yonghong.song@linux.dev
====================

Link: https://lore.kernel.org/r/20231020133202.4043247-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
borkmann pushed a commit that referenced this pull request Oct 24, 2023
Eduard Zingerman says:

====================
exact states comparison for iterator convergence checks

Iterator convergence logic in is_state_visited() uses state_equals()
for states with branches counter > 0 to check if iterator based loop
converges. This is not fully correct because state_equals() relies on
presence of read and precision marks on registers. These marks are not
guaranteed to be finalized while state has branches.
Commit message for patch #3 describes a program that exhibits such
behavior.

This patch-set aims to fix iterator convergence logic by adding notion
of exact states comparison. Exact comparison does not rely on presence
of read or precision marks and thus is more strict.
As explained in commit message for patch #3 exact comparisons require
addition of speculative register bounds widening. The end result for
BPF verifier users could be summarized as follows:

(!) After this update verifier would reject programs that conjure an
    imprecise value on the first loop iteration and use it as precise
    on the second (for iterator based loops).

I urge people to at least skim over the commit message for patch #3.

Patches are organized as follows:
- patches #1,2: moving/extracting utility functions;
- patch #3: introduces exact mode for states comparison and adds
  widening heuristic;
- patch #4: adds test-cases that demonstrate why the series is
  necessary;
- patch #5: extends patch #3 with a notion of state loop entries,
  these entries have to be tracked to correctly identify that
  different verifier states belong to the same states loop;
- patch #6: adds a test-case that demonstrates a program
  which requires loop entry tracking for correct verification;
- patch #7: just adds a few debug prints.

The following actions are planned as a followup for this patch-set:
- implementation has to be adapted for callbacks handling logic as a
  part of a fix for [1];
- it is necessary to explore ways to improve widening heuristic to
  handle iters_task_vma test w/o need to insert barrier_var() calls;
- explored states eviction logic on cache miss has to be extended
  to either:
  - allow eviction of checkpoint states -or-
  - be sped up in case if there are many active checkpoints associated
    with the same instruction.

The patch-set is a followup for mailing list discussion [1].

Changelog:
- V2 [3] -> V3:
  - correct check for stack spills in widen_imprecise_scalars(),
    added test case progs/iters.c:widen_spill to check the behavior
    (suggested by Andrii);
  - allow eviction of checkpoint states in is_state_visited() to avoid
    pathological verifier performance when iterator based loop does not
    converge (discussion with Alexei).
- V1 [2] -> V2, applied changes suggested by Alexei offlist:
  - __explored_state() function removed;
  - same_callsites() function is now used in clean_live_states();
  - patches #1,2 are added as preparatory code movement;
  - in process_iter_next_call() a safeguard is added to verify that
    cur_st->parent exists and has expected insn index / call sites.

[1] https://lore.kernel.org/bpf/97a90da09404c65c8e810cf83c94ac703705dc0e.camel@gmail.com/
[2] https://lore.kernel.org/bpf/20231021005939.1041-1-eddyz87@gmail.com/
[3] https://lore.kernel.org/bpf/20231022010812.9201-1-eddyz87@gmail.com/
====================

Link: https://lore.kernel.org/r/20231024000917.12153-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
borkmann pushed a commit that referenced this pull request Oct 27, 2023
Sachin reported a warning when running the inject-ra-err selftest:

  # selftests: powerpc/mce: inject-ra-err
  Disabling lock debugging due to kernel taint
  MCE: CPU19: machine check (Severe)  Real address Load/Store (foreign/control memory) [Not recovered]
  MCE: CPU19: PID: 5254 Comm: inject-ra-err NIP: [0000000010000e48]
  MCE: CPU19: Initiator CPU
  MCE: CPU19: Unknown
  ------------[ cut here ]------------
  WARNING: CPU: 19 PID: 5254 at arch/powerpc/mm/book3s64/radix_tlb.c:1221 radix__tlb_flush+0x160/0x180
  CPU: 19 PID: 5254 Comm: inject-ra-err Kdump: loaded Tainted: G   M        E      6.6.0-rc3-00055-g9ed22ae6be81 #4
  Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1030.20 (NH1030_058) hv:phyp pSeries
  ...
  NIP radix__tlb_flush+0x160/0x180
  LR  radix__tlb_flush+0x104/0x180
  Call Trace:
    radix__tlb_flush+0xf4/0x180 (unreliable)
    tlb_finish_mmu+0x15c/0x1e0
    exit_mmap+0x1a0/0x510
    __mmput+0x60/0x1e0
    exit_mm+0xdc/0x170
    do_exit+0x2bc/0x5a0
    do_group_exit+0x4c/0xc0
    sys_exit_group+0x28/0x30
    system_call_exception+0x138/0x330
    system_call_vectored_common+0x15c/0x2ec

And bisected it to commit e43c0a0 ("powerpc/64s/radix: combine
final TLB flush and lazy tlb mm shootdown IPIs"), which added a warning
in radix__tlb_flush() if mm->context.copros is still elevated.

However it's possible for the copros count to be elevated if a process
exits without first closing file descriptors that are associated with a
copro, eg. VAS.

If the process exits with a VAS file still open, the release callback
is queued up for exit_task_work() via:
  exit_files()
    put_files_struct()
      close_files()
        filp_close()
          fput()

And called via:
  exit_task_work()
    ____fput()
      __fput()
        file->f_op->release(inode, file)
          coproc_release()
            vas_user_win_ops->close_win()
              vas_deallocate_window()
                mm_context_remove_vas_window()
                  mm_context_remove_copro()

But that is after exit_mm() has been called from do_exit() and triggered
the warning.

Fix it by dropping the warning, and always calling __flush_all_mm().

In the normal case of no copros, that will result in a call to
_tlbiel_pid(mm->context.id, RIC_FLUSH_ALL) just as the current code
does.

If the copros count is elevated then it will cause a global flush, which
should flush translations from any copros. Note that the process table
entry was cleared in arch_exit_mmap(), so copros should not be able to
fetch any new translations.

Fixes: e43c0a0 ("powerpc/64s/radix: combine final TLB flush and lazy tlb mm shootdown IPIs")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Closes: https://lore.kernel.org/all/A8E52547-4BF1-47CE-8AEA-BC5A9D7E3567@linux.ibm.com/
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Link: https://msgid.link/20231017121527.1574104-1-mpe@ellerman.id.au
borkmann pushed a commit that referenced this pull request Oct 27, 2023
Jiri Pirko says:

====================
devlink: fix a deadlock when taking devlink instance lock while holding RTNL lock

devlink_port_fill() may be called sometimes with RTNL lock held.
When putting the nested port function devlink instance attrs,
current code takes nested devlink instance lock. In that case lock
ordering is wrong.

Patch #1 is a dependency of patch #2.
Patch #2 converts the peernet2id_alloc() call to rely in RCU so it could
         called without devlink instance lock.
Patch #3 takes device reference for devlink instance making sure that
         device does not disappear before devlink_release() is called.
Patch #4 benefits from the preparations done in patches #2 and #3 and
         removes the problematic nested devlink lock aquisition.
Patched #5-#7 improve documentation to reflect this issue so it is
              avoided in the future.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
borkmann pushed a commit that referenced this pull request May 19, 2025
When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
borkmann pushed a commit that referenced this pull request May 19, 2025
A warning on driver removal started occurring after commit 9dd05df
("net: warn if NAPI instance wasn't shut down"). Disable tx napi before
deleting it in mt76_dma_cleanup().

 WARNING: CPU: 4 PID: 18828 at net/core/dev.c:7288 __netif_napi_del_locked+0xf0/0x100
 CPU: 4 UID: 0 PID: 18828 Comm: modprobe Not tainted 6.15.0-rc4 #4 PREEMPT(lazy)
 Hardware name: ASUS System Product Name/PRIME X670E-PRO WIFI, BIOS 3035 09/05/2024
 RIP: 0010:__netif_napi_del_locked+0xf0/0x100
 Call Trace:
 <TASK>
 mt76_dma_cleanup+0x54/0x2f0 [mt76]
 mt7921_pci_remove+0xd5/0x190 [mt7921e]
 pci_device_remove+0x47/0xc0
 device_release_driver_internal+0x19e/0x200
 driver_detach+0x48/0x90
 bus_remove_driver+0x6d/0xf0
 pci_unregister_driver+0x2e/0xb0
 __do_sys_delete_module.isra.0+0x197/0x2e0
 do_syscall_64+0x7b/0x160
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Tested with mt7921e but the same pattern can be actually applied to other
mt76 drivers calling mt76_dma_cleanup() during removal. Tx napi is enabled
in their *_dma_init() functions and only toggled off and on again inside
their suspend/resume/reset paths. So it should be okay to disable tx
napi in such a generic way.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 2ac515a ("mt76: mt76x02: use napi polling for tx cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Tested-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250506115540.19045-1-pchelkin@ispras.ru
Signed-off-by: Felix Fietkau <nbd@nbd.name>
borkmann pushed a commit that referenced this pull request Aug 27, 2025
BPF CI testing report a UAF issue:

  [   16.446633] BUG: kernel NULL pointer dereference, address: 000000000000003  0
  [   16.447134] #PF: supervisor read access in kernel mod  e
  [   16.447516] #PF: error_code(0x0000) - not-present pag  e
  [   16.447878] PGD 0 P4D   0
  [   16.448063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPT  I
  [   16.448409] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Tainted: G           OE      6.13.0-rc3-g89e8a75fda73-dirty #4  2
  [   16.449124] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODUL  E
  [   16.449502] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/201  4
  [   16.450201] Workqueue: smc_hs_wq smc_listen_wor  k
  [   16.450531] RIP: 0010:smc_listen_work+0xc02/0x159  0
  [   16.452158] RSP: 0018:ffffb5ab40053d98 EFLAGS: 0001024  6
  [   16.452526] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000030  0
  [   16.452994] RDX: 0000000000000280 RSI: 00003513840053f0 RDI: 000000000000000  0
  [   16.453492] RBP: ffffa097808e3800 R08: ffffa09782dba1e0 R09: 000000000000000  5
  [   16.453987] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa0978274640  0
  [   16.454497] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa09782d4092  0
  [   16.454996] FS:  0000000000000000(0000) GS:ffffa097bbc00000(0000) knlGS:000000000000000  0
  [   16.455557] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003  3
  [   16.455961] CR2: 0000000000000030 CR3: 0000000102788004 CR4: 0000000000770ef  0
  [   16.456459] PKRU: 5555555  4
  [   16.456654] Call Trace  :
  [   16.456832]  <TASK  >
  [   16.456989]  ? __die+0x23/0x7  0
  [   16.457215]  ? page_fault_oops+0x180/0x4c  0
  [   16.457508]  ? __lock_acquire+0x3e6/0x249  0
  [   16.457801]  ? exc_page_fault+0x68/0x20  0
  [   16.458080]  ? asm_exc_page_fault+0x26/0x3  0
  [   16.458389]  ? smc_listen_work+0xc02/0x159  0
  [   16.458689]  ? smc_listen_work+0xc02/0x159  0
  [   16.458987]  ? lock_is_held_type+0x8f/0x10  0
  [   16.459284]  process_one_work+0x1ea/0x6d  0
  [   16.459570]  worker_thread+0x1c3/0x38  0
  [   16.459839]  ? __pfx_worker_thread+0x10/0x1  0
  [   16.460144]  kthread+0xe0/0x11  0
  [   16.460372]  ? __pfx_kthread+0x10/0x1  0
  [   16.460640]  ret_from_fork+0x31/0x5  0
  [   16.460896]  ? __pfx_kthread+0x10/0x1  0
  [   16.461166]  ret_from_fork_asm+0x1a/0x3  0
  [   16.461453]  </TASK  >
  [   16.461616] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE)  ]
  [   16.462134] CR2: 000000000000003  0
  [   16.462380] ---[ end trace 0000000000000000 ]---
  [   16.462710] RIP: 0010:smc_listen_work+0xc02/0x1590

The direct cause of this issue is that after smc_listen_out_connected(),
newclcsock->sk may be NULL since it will releases the smcsk. Therefore,
if the application closes the socket immediately after accept,
newclcsock->sk can be NULL. A possible execution order could be as
follows:

smc_listen_work                                 | userspace
-----------------------------------------------------------------
lock_sock(sk)                                   |
smc_listen_out_connected()                      |
| \- smc_listen_out                             |
|    | \- release_sock                          |
     | |- sk->sk_data_ready()                   |
                                                | fd = accept();
                                                | close(fd);
                                                |  \- socket->sk = NULL;
/* newclcsock->sk is NULL now */
SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk))

Since smc_listen_out_connected() will not fail, simply swapping the order
of the code can easily fix this issue.

Fixes: 3b2dec2 ("net/smc: restructure client and server code in af_smc")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/20250818054618.41615-1-alibuda@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
borkmann pushed a commit that referenced this pull request Sep 18, 2025
These iterations require the read lock, otherwise RCU
lockdep will splat:

=============================
WARNING: suspicious RCU usage
6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G           O
-----------------------------
drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
5 locks held by rtcwake/547:
 #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a
 #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b
 #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b
 #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b
 #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98

stack backtrace:
CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G           O        6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY
Tainted: [O]=OOT_MODULE
Stack:
 223721b3a80 6089eac6 00000001 00000001
 ffffff00 6089eac6 00000535 6086e528
 721b3ac0 6003c294 00000000 60031fc0
Call Trace:
 [<600407ed>] show_stack+0x10e/0x127
 [<6003c294>] dump_stack_lvl+0x77/0xc6
 [<6003c2fd>] dump_stack+0x1a/0x20
 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e
 [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e
 [<603d980f>] device_suspend+0x528/0x541
 [<603da24b>] dpm_suspend+0x1a2/0x267
 [<603da837>] dpm_suspend_start+0x5d/0x72
 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736
 [...]

Add the fourth argument to the iteration to annotate
this and avoid the splat.

Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents")
Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
borkmann pushed a commit that referenced this pull request Sep 18, 2025
Ido Schimmel says:

====================
ipv4: icmp: Fix source IP derivation in presence of VRFs

Align IPv4 with IPv6 and in the presence of VRFs generate ICMP error
messages with a source IP that is derived from the receiving interface
and not from its VRF master. This is especially important when the error
messages are "Time Exceeded" messages as it means that utilities like
traceroute will show an incorrect packet path.

Patches #1-#2 are preparations.

Patch #3 is the actual change.

Patches #4-#7 make small improvements in the existing traceroute test.

Patch #8 extends the traceroute test with VRF test cases for both IPv4
and IPv6.

Changes since v1 [1]:
* Rebase.

[1] https://lore.kernel.org/netdev/20250901083027.183468-1-idosch@nvidia.com/
====================

Link: https://patch.msgid.link/20250908073238.119240-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
borkmann pushed a commit that referenced this pull request Sep 19, 2025
Michael Chan says:

====================
bnxt_en: Updates for net-next

This series includes some code clean-ups and optimizations.  New features
include 2 new backing store memory types to collect FW logs for core
dumps, dynamic SRIOV resource allocations for RoCE, and ethtool tunable
for PFC watchdog.

v2: Drop patch #4.  The patch makes the code different from the original
bnxt_hwrm_func_backing_store_cfg_v2() that allows instance_bmap to have
bits that are not contiguous.  It is safer to keep the original code.

v1: https://lore.kernel.org/netdev/20250915030505.1803478-1-michael.chan@broadcom.com/
====================

Link: https://patch.msgid.link/20250917040839.1924698-1-michael.chan@broadcom.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
borkmann pushed a commit that referenced this pull request Oct 20, 2025
Since blamed commit, unregister_netdevice_many_notify() takes the netdev
mutex if the device needs it.

If the device list is too long, this will lock more device mutexes than
lockdep can handle:

unshare -n \
 bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done'

BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48  max: 48!
48 locks held by kworker/u16:1/69:
 #0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work
 #1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work
 #2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net
 #3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch
 #4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify
[..]

Add a helper to close and then unlock a list of net_devices.
Devices that are not up have to be skipped - netif_close_many always
removes them from the list without any other actions taken, so they'd
remain in locked state.

Close devices whenever we've used up half of the tracking slots or we
processed entire list without hitting the limit.

Fixes: 7e4d784 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20251013185052.14021-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
borkmann pushed a commit that referenced this pull request Oct 24, 2025
…ked_roots()

If fs_info->super_copy or fs_info->super_for_commit allocated failed in
btrfs_get_tree_subvol(), then no need to call btrfs_free_fs_info().
Otherwise btrfs_check_leaked_roots() would access NULL pointer because
fs_info->allocated_roots had not been initialised.

syzkaller reported the following information:
  ------------[ cut here ]------------
  BUG: unable to handle page fault for address: fffffffffffffbb0
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 64c9067 P4D 64c9067 PUD 64cb067 PMD 0
  Oops: Oops: 0000 [#1] SMP KASAN PTI
  CPU: 0 UID: 0 PID: 1402 Comm: syz.1.35 Not tainted 6.15.8 #4 PREEMPT(lazy)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), (...)
  RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
  RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
  RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
  RIP: 0010:refcount_read include/linux/refcount.h:170 [inline]
  RIP: 0010:btrfs_check_leaked_roots+0x18f/0x2c0 fs/btrfs/disk-io.c:1230
  [...]
  Call Trace:
   <TASK>
   btrfs_free_fs_info+0x310/0x410 fs/btrfs/disk-io.c:1280
   btrfs_get_tree_subvol+0x592/0x6b0 fs/btrfs/super.c:2029
   btrfs_get_tree+0x63/0x80 fs/btrfs/super.c:2097
   vfs_get_tree+0x98/0x320 fs/super.c:1759
   do_new_mount+0x357/0x660 fs/namespace.c:3899
   path_mount+0x716/0x19c0 fs/namespace.c:4226
   do_mount fs/namespace.c:4239 [inline]
   __do_sys_mount fs/namespace.c:4450 [inline]
   __se_sys_mount fs/namespace.c:4427 [inline]
   __x64_sys_mount+0x28c/0x310 fs/namespace.c:4427
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0x92/0x180 arch/x86/entry/syscall_64.c:94
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f032eaffa8d
  [...]

Fixes: 3bb17a2 ("btrfs: add get_tree callback for new mount API")
CC: stable@vger.kernel.org # 6.12+
Reviewed-by: Daniel Vacek <neelx@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Dewei Meng <mengdewei@cqsoftware.com.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
borkmann pushed a commit that referenced this pull request Oct 31, 2025
The original code causes a circular locking dependency found by lockdep.

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S   U
------------------------------------------------------
xe_fault_inject/5091 is trying to acquire lock:
ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660

but task is already holding lock:

ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&devcd->mutex){+.+.}-{3:3}:
       mutex_lock_nested+0x4e/0xc0
       devcd_data_write+0x27/0x90
       sysfs_kf_bin_write+0x80/0xf0
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (kn->active#236){++++}-{0:0}:
       kernfs_drain+0x1e2/0x200
       __kernfs_remove+0xae/0x400
       kernfs_remove_by_name_ns+0x5d/0xc0
       remove_files+0x54/0x70
       sysfs_remove_group+0x3d/0xa0
       sysfs_remove_groups+0x2e/0x60
       device_remove_attrs+0xc7/0x100
       device_del+0x15d/0x3b0
       devcd_del+0x19/0x30
       process_one_work+0x22b/0x6f0
       worker_thread+0x1e8/0x3d0
       kthread+0x11c/0x250
       ret_from_fork+0x26c/0x2e0
       ret_from_fork_asm+0x1a/0x30
-> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}:
       __lock_acquire+0x1661/0x2860
       lock_acquire+0xc4/0x2f0
       __flush_work+0x27a/0x660
       flush_delayed_work+0x5d/0xa0
       dev_coredump_put+0x63/0xa0
       xe_driver_devcoredump_fini+0x12/0x20 [xe]
       devm_action_release+0x12/0x30
       release_nodes+0x3a/0x120
       devres_release_all+0x8a/0xd0
       device_unbind_cleanup+0x12/0x80
       device_release_driver_internal+0x23a/0x280
       device_driver_detach+0x14/0x20
       unbind_store+0xaf/0xc0
       drv_attr_store+0x21/0x50
       sysfs_kf_write+0x4a/0x80
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
other info that might help us debug this:
Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&devcd->mutex);
                               lock(kn->active#236);
                               lock(&devcd->mutex);
  lock((work_completion)(&(&devcd->del_wk)->work));
 *** DEADLOCK ***
5 locks held by xe_fault_inject/5091:
 #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0
 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220
 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280
 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660
stack backtrace:
CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S   U              6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)}
Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 dump_stack+0x10/0x20
 print_circular_bug+0x285/0x360
 check_noncircular+0x135/0x150
 ? register_lock_class+0x48/0x4a0
 __lock_acquire+0x1661/0x2860
 lock_acquire+0xc4/0x2f0
 ? __flush_work+0x25d/0x660
 ? mark_held_locks+0x46/0x90
 ? __flush_work+0x25d/0x660
 __flush_work+0x27a/0x660
 ? __flush_work+0x25d/0x660
 ? trace_hardirqs_on+0x1e/0xd0
 ? __pfx_wq_barrier_func+0x10/0x10
 flush_delayed_work+0x5d/0xa0
 dev_coredump_put+0x63/0xa0
 xe_driver_devcoredump_fini+0x12/0x20 [xe]
 devm_action_release+0x12/0x30
 release_nodes+0x3a/0x120
 devres_release_all+0x8a/0xd0
 device_unbind_cleanup+0x12/0x80
 device_release_driver_internal+0x23a/0x280
 ? bus_find_device+0xa8/0xe0
 device_driver_detach+0x14/0x20
 unbind_store+0xaf/0xc0
 drv_attr_store+0x21/0x50
 sysfs_kf_write+0x4a/0x80
 kernfs_fop_write_iter+0x169/0x220
 vfs_write+0x293/0x560
 ksys_write+0x72/0xf0
 __x64_sys_write+0x19/0x30
 x64_sys_call+0x2bf/0x2660
 do_syscall_64+0x93/0xb60
 ? __f_unlock_pos+0x15/0x20
 ? __x64_sys_getdents64+0x9b/0x130
 ? __pfx_filldir64+0x10/0x10
 ? do_syscall_64+0x1a2/0xb60
 ? clear_bhb_loop+0x30/0x80
 ? clear_bhb_loop+0x30/0x80
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x76e292edd574
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574
RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b
RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063
R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000
 </TASK>
xe 0000:03:00.0: [drm] Xe device coredump has been deleted.

Fixes: 01daccf ("devcoredump : Serialize devcd_del work")
Cc: Mukesh Ojha <quic_mojha@quicinc.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
Cc: Matthew Brost <matthew.brost@intel.com>
Acked-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250723142416.1020423-1-dev@lankhorst.se
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
borkmann pushed a commit that referenced this pull request Nov 18, 2025
Michael Chan says:

====================
bnxt_en: Bug fixes

Patches 1, 3, and 4 are bug fixes related to the FW log tracing driver
coredump feature recently added in 6.13.  Patch #1 adds the necessary
call to shutdown the FW logging DMA during PCI shutdown.  Patch #3 fixes
a possible null pointer derefernce when using early versions of the FW
with this feature.  Patch #4 adds the coredump header information
unconditionally to make it more robust.

Patch #2 fixes a possible memory leak during PTP shutdown.  Patch #5
eliminates a dmesg warning when doing devlink reload.
====================

Link: https://patch.msgid.link/20251104005700.542174-1-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
borkmann pushed a commit that referenced this pull request Nov 18, 2025
On completion of i915_vma_pin_ww(), a synchronous variant of
dma_fence_work_commit() is called.  When pinning a VMA to GGTT address
space on a Cherry View family processor, or on a Broxton generation SoC
with VTD enabled, i.e., when stop_machine() is then called from
intel_ggtt_bind_vma(), that can potentially lead to lock inversion among
reservation_ww and cpu_hotplug locks.

[86.861179] ======================================================
[86.861193] WARNING: possible circular locking dependency detected
[86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G     U
[86.861226] ------------------------------------------------------
[86.861238] i915_module_loa/1432 is trying to acquire lock:
[86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50
[86.861290]
but task is already holding lock:
[86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.862233]
which lock already depends on the new lock.
[86.862251]
the existing dependency chain (in reverse order) is:
[86.862265]
-> #5 (reservation_ww_class_mutex){+.+.}-{3:3}:
[86.862292]        dma_resv_lockdep+0x19a/0x390
[86.862315]        do_one_initcall+0x60/0x3f0
[86.862334]        kernel_init_freeable+0x3cd/0x680
[86.862353]        kernel_init+0x1b/0x200
[86.862369]        ret_from_fork+0x47/0x70
[86.862383]        ret_from_fork_asm+0x1a/0x30
[86.862399]
-> #4 (reservation_ww_class_acquire){+.+.}-{0:0}:
[86.862425]        dma_resv_lockdep+0x178/0x390
[86.862440]        do_one_initcall+0x60/0x3f0
[86.862454]        kernel_init_freeable+0x3cd/0x680
[86.862470]        kernel_init+0x1b/0x200
[86.862482]        ret_from_fork+0x47/0x70
[86.862495]        ret_from_fork_asm+0x1a/0x30
[86.862509]
-> #3 (&mm->mmap_lock){++++}-{3:3}:
[86.862531]        down_read_killable+0x46/0x1e0
[86.862546]        lock_mm_and_find_vma+0xa2/0x280
[86.862561]        do_user_addr_fault+0x266/0x8e0
[86.862578]        exc_page_fault+0x8a/0x2f0
[86.862593]        asm_exc_page_fault+0x27/0x30
[86.862607]        filldir64+0xeb/0x180
[86.862620]        kernfs_fop_readdir+0x118/0x480
[86.862635]        iterate_dir+0xcf/0x2b0
[86.862648]        __x64_sys_getdents64+0x84/0x140
[86.862661]        x64_sys_call+0x1058/0x2660
[86.862675]        do_syscall_64+0x91/0xe90
[86.862689]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.862703]
-> #2 (&root->kernfs_rwsem){++++}-{3:3}:
[86.862725]        down_write+0x3e/0xf0
[86.862738]        kernfs_add_one+0x30/0x3c0
[86.862751]        kernfs_create_dir_ns+0x53/0xb0
[86.862765]        internal_create_group+0x134/0x4c0
[86.862779]        sysfs_create_group+0x13/0x20
[86.862792]        topology_add_dev+0x1d/0x30
[86.862806]        cpuhp_invoke_callback+0x4b5/0x850
[86.862822]        cpuhp_issue_call+0xbf/0x1f0
[86.862836]        __cpuhp_setup_state_cpuslocked+0x111/0x320
[86.862852]        __cpuhp_setup_state+0xb0/0x220
[86.862866]        topology_sysfs_init+0x30/0x50
[86.862879]        do_one_initcall+0x60/0x3f0
[86.862893]        kernel_init_freeable+0x3cd/0x680
[86.862908]        kernel_init+0x1b/0x200
[86.862921]        ret_from_fork+0x47/0x70
[86.862934]        ret_from_fork_asm+0x1a/0x30
[86.862947]
-> #1 (cpuhp_state_mutex){+.+.}-{3:3}:
[86.862969]        __mutex_lock+0xaa/0xed0
[86.862982]        mutex_lock_nested+0x1b/0x30
[86.862995]        __cpuhp_setup_state_cpuslocked+0x67/0x320
[86.863012]        __cpuhp_setup_state+0xb0/0x220
[86.863026]        page_alloc_init_cpuhp+0x2d/0x60
[86.863041]        mm_core_init+0x22/0x2d0
[86.863054]        start_kernel+0x576/0xbd0
[86.863068]        x86_64_start_reservations+0x18/0x30
[86.863084]        x86_64_start_kernel+0xbf/0x110
[86.863098]        common_startup_64+0x13e/0x141
[86.863114]
-> #0 (cpu_hotplug_lock){++++}-{0:0}:
[86.863135]        __lock_acquire+0x1635/0x2810
[86.863152]        lock_acquire+0xc4/0x2f0
[86.863166]        cpus_read_lock+0x41/0x100
[86.863180]        stop_machine+0x1c/0x50
[86.863194]        bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.863987]        intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.864735]        __vma_bind+0x55/0x70 [i915]
[86.865510]        fence_work+0x26/0xa0 [i915]
[86.866248]        fence_notify+0xa1/0x140 [i915]
[86.866983]        __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.867719]        i915_sw_fence_commit+0x39/0x60 [i915]
[86.868453]        i915_vma_pin_ww+0x462/0x1360 [i915]
[86.869228]        i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.870001]        initial_plane_vma+0x307/0x840 [i915]
[86.870774]        intel_initial_plane_config+0x33f/0x670 [i915]
[86.871546]        intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.872330]        i915_driver_probe+0x7fa/0xe80 [i915]
[86.873057]        i915_pci_probe+0xe6/0x220 [i915]
[86.873782]        local_pci_probe+0x47/0xb0
[86.873802]        pci_device_probe+0xf3/0x260
[86.873817]        really_probe+0xf1/0x3c0
[86.873833]        __driver_probe_device+0x8c/0x180
[86.873848]        driver_probe_device+0x24/0xd0
[86.873862]        __driver_attach+0x10f/0x220
[86.873876]        bus_for_each_dev+0x7f/0xe0
[86.873892]        driver_attach+0x1e/0x30
[86.873904]        bus_add_driver+0x151/0x290
[86.873917]        driver_register+0x5e/0x130
[86.873931]        __pci_register_driver+0x7d/0x90
[86.873945]        i915_pci_register_driver+0x23/0x30 [i915]
[86.874678]        i915_init+0x37/0x120 [i915]
[86.875347]        do_one_initcall+0x60/0x3f0
[86.875369]        do_init_module+0x97/0x2a0
[86.875385]        load_module+0x2c54/0x2d80
[86.875398]        init_module_from_file+0x96/0xe0
[86.875413]        idempotent_init_module+0x117/0x330
[86.875426]        __x64_sys_finit_module+0x77/0x100
[86.875440]        x64_sys_call+0x24de/0x2660
[86.875454]        do_syscall_64+0x91/0xe90
[86.875470]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.875486]
other info that might help us debug this:
[86.875502] Chain exists of:
  cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex
[86.875539]  Possible unsafe locking scenario:
[86.875552]        CPU0                    CPU1
[86.875563]        ----                    ----
[86.875573]   lock(reservation_ww_class_mutex);
[86.875588]                                lock(reservation_ww_class_acquire);
[86.875606]                                lock(reservation_ww_class_mutex);
[86.875624]   rlock(cpu_hotplug_lock);
[86.875637]
 *** DEADLOCK ***
[86.875650] 3 locks held by i915_module_loa/1432:
[86.875663]  #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220
[86.875699]  #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.876512]  #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.877305]
stack backtrace:
[86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G     U              6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary)
[86.877334] Tainted: [U]=USER
[86.877336] Hardware name:  /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020
[86.877339] Call Trace:
[86.877344]  <TASK>
[86.877353]  dump_stack_lvl+0x91/0xf0
[86.877364]  dump_stack+0x10/0x20
[86.877369]  print_circular_bug+0x285/0x360
[86.877379]  check_noncircular+0x135/0x150
[86.877390]  __lock_acquire+0x1635/0x2810
[86.877403]  lock_acquire+0xc4/0x2f0
[86.877408]  ? stop_machine+0x1c/0x50
[86.877422]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878173]  cpus_read_lock+0x41/0x100
[86.878182]  ? stop_machine+0x1c/0x50
[86.878191]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878916]  stop_machine+0x1c/0x50
[86.878927]  bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.879652]  intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.880375]  __vma_bind+0x55/0x70 [i915]
[86.881133]  fence_work+0x26/0xa0 [i915]
[86.881851]  fence_notify+0xa1/0x140 [i915]
[86.882566]  __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.883286]  i915_sw_fence_commit+0x39/0x60 [i915]
[86.884003]  i915_vma_pin_ww+0x462/0x1360 [i915]
[86.884756]  ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915]
[86.885513]  i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.886281]  initial_plane_vma+0x307/0x840 [i915]
[86.887049]  intel_initial_plane_config+0x33f/0x670 [i915]
[86.887819]  intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.888587]  i915_driver_probe+0x7fa/0xe80 [i915]
[86.889293]  ? mutex_unlock+0x12/0x20
[86.889301]  ? drm_privacy_screen_get+0x171/0x190
[86.889308]  ? acpi_dev_found+0x66/0x80
[86.889321]  i915_pci_probe+0xe6/0x220 [i915]
[86.890038]  local_pci_probe+0x47/0xb0
[86.890049]  pci_device_probe+0xf3/0x260
[86.890058]  really_probe+0xf1/0x3c0
[86.890067]  __driver_probe_device+0x8c/0x180
[86.890072]  driver_probe_device+0x24/0xd0
[86.890078]  __driver_attach+0x10f/0x220
[86.890083]  ? __pfx___driver_attach+0x10/0x10
[86.890088]  bus_for_each_dev+0x7f/0xe0
[86.890097]  driver_attach+0x1e/0x30
[86.890101]  bus_add_driver+0x151/0x290
[86.890107]  driver_register+0x5e/0x130
[86.890113]  __pci_register_driver+0x7d/0x90
[86.890119]  i915_pci_register_driver+0x23/0x30 [i915]
[86.890833]  i915_init+0x37/0x120 [i915]
[86.891482]  ? __pfx_i915_init+0x10/0x10 [i915]
[86.892135]  do_one_initcall+0x60/0x3f0
[86.892145]  ? __kmalloc_cache_noprof+0x33f/0x470
[86.892157]  do_init_module+0x97/0x2a0
[86.892164]  load_module+0x2c54/0x2d80
[86.892168]  ? __kernel_read+0x15c/0x300
[86.892185]  ? kernel_read_file+0x2b1/0x320
[86.892195]  init_module_from_file+0x96/0xe0
[86.892199]  ? init_module_from_file+0x96/0xe0
[86.892211]  idempotent_init_module+0x117/0x330
[86.892224]  __x64_sys_finit_module+0x77/0x100
[86.892230]  x64_sys_call+0x24de/0x2660
[86.892236]  do_syscall_64+0x91/0xe90
[86.892243]  ? irqentry_exit+0x77/0xb0
[86.892249]  ? sysvec_apic_timer_interrupt+0x57/0xc0
[86.892256]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.892261] RIP: 0033:0x7303e1b2725d
[86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48
[86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d
[86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c
[86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80
[86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0
[86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710
[86.892304]  </TASK>

Call asynchronous variant of dma_fence_work_commit() in that case.

v3: Provide more verbose in-line comment (Andi),
  - mention target environments in commit message.

Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985
Cc: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com>
Acked-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://lore.kernel.org/r/20251023082925.351307-6-janusz.krzysztofik@linux.intel.com
(cherry picked from commit 648ef13)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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