BUG: soft lockup in mrp_join_timer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cb83ddcd Linux 4.14.226
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=101e90bed00000
kernel config: https://syzkaller.appspot.com/x/.config?x=124f4e6b89b71fac
dashboard link: https://syzkaller.appspot.com/bug?extid=03d2396b54bdd36ea523

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+03d239...@syzkaller.appspotmail.com

netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'.
hid-generic 0000:0000:0000.0001: hidraw0: <UNKNOWN> HID v0.00 Device [syz0] on syz1
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz-executor.0:28342]
Modules linked in:
irq event stamp: 5150687
hardirqs last enabled at (5150686): [<ffffffff87400976>] restore_regs_and_return_to_kernel+0x0/0x2a
hardirqs last disabled at (5150687): [<ffffffff874018ae>] apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:793
softirqs last enabled at (486): [<ffffffff8760068b>] __do_softirq+0x68b/0x9ff kernel/softirq.c:314
softirqs last disabled at (1677): [<ffffffff81320ae3>] invoke_softirq kernel/softirq.c:368 [inline]
softirqs last disabled at (1677): [<ffffffff81320ae3>] irq_exit+0x193/0x240 kernel/softirq.c:409
CPU: 0 PID: 28342 Comm: syz-executor.0 Not tainted 4.14.226-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880991c2300 task.stack: ffff8882221e8000
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
RIP: 0010:do_raw_spin_lock+0x3e/0x200 kernel/locking/spinlock_debug.c:112
RSP: 0018:ffff8880ba407d00 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 00000000dead4ead RBX: ffff888096a0d090 RCX: 000000000000008b
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888096a0d134
RBP: ffff888096a0d130 R08: ffffffff8b989f18 R09: 00000000000425ef
R10: ffff8880991c2bd8 R11: ffff8880991c2300 R12: ffff888096a0d080
R13: 1ffff11017480fae R14: ffff888096a0d130 R15: 0000000000000000
FS: 00007fdc7a16a700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e4a62 CR3: 000000022d61a000 CR4: 00000000001426f0
DR0: 0000000000000101 DR1: 0000000000000000 DR2: 0000000000000005
DR3: 00000000000006a5 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
spin_lock include/linux/spinlock.h:317 [inline]
mrp_join_timer+0x1f/0xc0 net/802/mrp.c:593
call_timer_fn+0x14a/0x650 kernel/time/timer.c:1280
expire_timers+0x232/0x4d0 kernel/time/timer.c:1319
__run_timers kernel/time/timer.c:1637 [inline]
run_timer_softirq+0x1d5/0x5a0 kernel/time/timer.c:1650
__do_softirq+0x24d/0x9ff kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x193/0x240 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:638 [inline]
smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1106
apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
</IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:27 [inline]
RIP: 0010:queued_spin_is_locked include/asm-generic/qspinlock.h:36 [inline]
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:98 [inline]
RIP: 0010:do_raw_spin_unlock+0x65/0x220 kernel/locking/spinlock_debug.c:134
RSP: 0018:ffff8882221efc18 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000003 RBX: dffffc0000000000 RCX: 1ffff11013238576
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff88804e92c73c
RBP: ffff88804e92c738 R08: ffffffff8b9b03d8 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8880991c2300 R12: 00007fc149c2a000
R13: ffff88801381ec68 R14: ffff88801381ec60 R15: ffff88804e92c738
__raw_spin_unlock include/linux/spinlock_api_smp.h:151 [inline]
_raw_spin_unlock+0x1f/0x40 kernel/locking/spinlock.c:184
spin_unlock include/linux/spinlock.h:357 [inline]
browse_rb mm/mmap.c:318 [inline]
validate_mm+0x32a/0x580 mm/mmap.c:378
mmap_region+0xa95/0x1220 mm/mmap.c:1738
do_mmap+0x5b3/0xcb0 mm/mmap.c:1495
do_mmap_pgoff include/linux/mm.h:2185 [inline]
vm_mmap_pgoff+0x14e/0x1a0 mm/util.c:333
SYSC_mmap_pgoff mm/mmap.c:1545 [inline]
SyS_mmap_pgoff+0x249/0x510 mm/mmap.c:1503
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007fdc7a16a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000466459
RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffc000
RBP: 00000000004bf9fb R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 000000000056c008
R13: 00007ffd67e53e2f R14: 00007fdc7a16a300 R15: 0000000000022000
Code: 83 c7 04 48 89 fa 53 48 c1 ea 03 48 83 ec 08 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 86 01 00 00 8b 45 04 <3d> ad 4e ad de 0f 85 36 01 00 00 4c 8d 6d 10 48 b8 00 00 00 00
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff872134ae


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[syzbot]

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