INFO: trying to register non-static key in cpuset_change_task_nodemask

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 56b697c6 Add linux-next specific files for 20190604
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=163b554aa00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4248d6bc70076f7d
dashboard link: https://syzkaller.appspot.com/bug?extid=e7d5c8b48baf817bc820
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [cgr...@vger.kernel.org han...@cmpxchg.org
linux-...@vger.kernel.org liz...@huawei.com t...@kernel.org]

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+e7d5c8...@syzkaller.appspotmail.com

INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 30774 Comm: syz-executor.5 Not tainted 5.2.0-rc3-next-20190604
#8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
assign_lock_key kernel/locking/lockdep.c:776 [inline]
register_lock_class+0x176c/0x1820 kernel/locking/lockdep.c:1085
__lock_acquire+0x116/0x5490 kernel/locking/lockdep.c:3671
lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4300
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
spin_lock include/linux/spinlock.h:338 [inline]
task_lock include/linux/sched/task.h:148 [inline]
cpuset_change_task_nodemask+0x2b/0x290 kernel/cgroup/cpuset.c:1599
update_tasks_nodemask+0xf6/0x210 kernel/cgroup/cpuset.c:1649
update_nodemasks_hier kernel/cgroup/cpuset.c:1722 [inline]
update_nodemask kernel/cgroup/cpuset.c:1790 [inline]
cpuset_write_resmask+0x7b3/0x2030 kernel/cgroup/cpuset.c:2353
cgroup_file_write+0x241/0x790 kernel/cgroup/cgroup.c:3711
kernfs_fop_write+0x2b8/0x480 fs/kernfs/file.c:316
__vfs_write+0x8a/0x110 fs/read_write.c:494
vfs_write+0x268/0x5d0 fs/read_write.c:558
ksys_write+0x14f/0x290 fs/read_write.c:611
__do_sys_write fs/read_write.c:623 [inline]
__se_sys_write fs/read_write.c:620 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:620
do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459279
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007efd8250bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279
RDX: 00000000000001e4 RSI: 0000000020000080 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007efd8250c6d4
R13: 00000000004c8ed3 R14: 00000000004dfb98 R15: 00000000ffffffff


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.