linux-next boot error: BUG: Invalid wait context ]

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: fb57b1fa Add linux-next specific files for 20200519
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17c9196e100000
kernel config: https://syzkaller.appspot.com/x/.config?x=2522f758a3588c2d
dashboard link: https://syzkaller.appspot.com/bug?extid=08003d278f04ed0944e0
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+08003d...@syzkaller.appspotmail.com

=============================
[ BUG: Invalid wait context ]
5.7.0-rc6-next-20200519-syzkaller #0 Not tainted
-----------------------------
swapper/1/0 is trying to lock:
ffff8880ae737518 (&pool->lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:353 [inline]
ffff8880ae737518 (&pool->lock){..-.}-{3:3}, at: __queue_work+0x2bf/0x1350 kernel/workqueue.c:1448
other info that might help us debug this:
context-{2:2}
1 lock held by swapper/1/0:
#0: ffffffff89bc0040 (rcu_read_lock){....}-{1:3}, at: __queue_work+0x175/0x1350 kernel/workqueue.c:1411
stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.7.0-rc6-next-20200519-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x18f/0x20d lib/dump_stack.c:118
print_lock_invalid_wait_context kernel/locking/lockdep.c:3988 [inline]
check_wait_context kernel/locking/lockdep.c:4049 [inline]
__lock_acquire.cold+0x26c/0x458 kernel/locking/lockdep.c:4286
lock_acquire+0x20e/0x960 kernel/locking/lockdep.c:4915
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
spin_lock include/linux/spinlock.h:353 [inline]
__queue_work+0x2bf/0x1350 kernel/workqueue.c:1448
queue_work_on+0x18b/0x200 kernel/workqueue.c:1517
tick_nohz_activate kernel/time/tick-sched.c:1244 [inline]
tick_nohz_activate kernel/time/tick-sched.c:1237 [inline]
tick_setup_sched_timer+0x20e/0x380 kernel/time/tick-sched.c:1378
hrtimer_switch_to_hres kernel/time/hrtimer.c:739 [inline]
hrtimer_run_queues+0x327/0x3e0 kernel/time/hrtimer.c:1746
run_local_timers+0x49/0x130 kernel/time/timer.c:1798
update_process_times+0x1e/0x60 kernel/time/timer.c:1725
tick_periodic+0x79/0x170 kernel/time/tick-common.c:99
tick_handle_periodic+0x41/0x130 kernel/time/tick-common.c:111
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
smp_apic_timer_interrupt+0x1ad/0x6a0 arch/x86/kernel/apic/apic.c:1105
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
</IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: cc cc cc cc cc cc cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 74 91 59 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 64 91 59 00 fb f4 <c3> cc 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 41 55 41 54 55 53
RSP: 0000:ffffc90000d3fd50 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1369a43 RBX: 1ffff920001a7fab RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a95f0c0c
RBP: dffffc0000000000 R08: ffff8880a95f0340 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffed10152be068
R13: 0000000000000001 R14: ffffffff8aabeb08 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline]
default_idle+0x91/0x3d0 arch/x86/kernel/process.c:708
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x393/0x690 kernel/sched/idle.c:269
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361
start_secondary+0x2f8/0x410 arch/x86/kernel/smpboot.c:268
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
random: fast init done
random: 7 urandom warning(s) missed due to ratelimiting


---
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[Thomas Gleixner]

syzbot <syzbot+08003d...@syzkaller.appspotmail.com> writes:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: fb57b1fa Add linux-next specific files for 20200519
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=17c9196e100000
> kernel config: https://syzkaller.appspot.com/x/.config?x=2522f758a3588c2d
> dashboard link: https://syzkaller.appspot.com/bug?extid=08003d278f04ed0944e0
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+08003d...@syzkaller.appspotmail.com
>
> =============================
> [ BUG: Invalid wait context ]
> 5.7.0-rc6-next-20200519-syzkaller #0 Not tainted
> -----------------------------
> swapper/1/0 is trying to lock:
> ffff8880ae737518 (&pool->lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:353 [inline]
> ffff8880ae737518 (&pool->lock){..-.}-{3:3}, at: __queue_work+0x2bf/0x1350 kernel/workqueue.c:1448

Can you please disable CONFIG_PROVE_RAW_LOCK_NESTING for now?

From the help text:

NOTE:
There are known nesting problems. So if you enable this option expect
lockdep splats until these problems have been fully addressed which is
work in progress. This config switch allows to identify and analyze
these problems. It will be removed and the check permanentely enabled
once the main issues have been fixed.

Thanks,

tglx

[Dmitry Vyukov]

Hi Thomas,

Done:
https://github.com/google/syzkaller/commit/4afdfa205b55633e7eb9db03a9d099d7aa324801

We can obsolete this then:

#syz invalid