assertion failed: spin_locked(lock)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 9196d29ad275 qio: Fix Qmsg panic in read_all_blocks()
git tree: https://github.com/akaros/akaros.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=12757a58400000
kernel config: https://syzkaller.appspot.com/x/.config?x=efef8cf2939304d3
dashboard link: https://syzkaller.appspot.com/bug?extid=c67193809ee7bd973732
compiler:

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+c67193...@syzkaller.appspotmail.com

kernel panic at kern/src/atomic.c:98, from core 3: assertion failed:
spin_locked(lock)
Stack Backtrace on Core 3:
#01 [<0xffffffffc200a2bc>] in backtrace at src/kdebug.c:220
#02 [<0xffffffffc2009afd>] in _panic at src/init.c:268
#03 [<0xffffffffc2003a55>] in spin_unlock at src/atomic.c:98
#04 [< [inline] >] in spin_unlock_irqsave at include/atomic.h:302
#04 [< [inline] >] in __set_alarm_rkm at src/alarm.c:261
#04 [<0xffffffffc2000670>] in set_alarm at src/alarm.c:271
#05 [< [inline] >] in set_proc_alarm at drivers/dev/alarm.c:447
#05 [<0xffffffffc207235f>] in alarmwrite at drivers/dev/alarm.c:468
#06 [<0xffffffffc2040221>] in rwrite at src/ns/sysfile.c:1123
#07 [<0xffffffffc204043b>] in syswrite at src/ns/sysfile.c:1141
#08 [<0xffffffffc2055f61>] in sys_write at src/syscall.c:1785
#09 [<0xffffffffc2059439>] in syscall at src/syscall.c:2528
#10 [<0xffffffffc2059604>] in run_local_syscall at src/syscall.c:2563
#11 [<0xffffffffc2059b39>] in prep_syscalls at src/syscall.c:2583
#12 [<0xffffffffc20ab38a>] in sysenter_callwrapper at arch/x86/trap.c:854
kernel panic at kern/src/rcu.c:323, from core 2: assertion failed:
rpi->gp_acked + 1 == READ_ONCE(rsp->gpnum)
Stack Backtrace on Core 2:
#01 [<0xffffffffc200a2bc>] in backtrace at src/kdebug.c:220
#02 [<0xffffffffc2009afd>] in _panic at src/init.c:268
#03 [<0xffffffffc20504fb>] in rcu_report_qs_rpi at src/rcu.c:323
#04 [<0xffffffffc2050edc>] in rcu_report_qs at src/rcu.c:338
#05 [<0xffffffffc2054633>] in __smp_idle at src/smp.c:75


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[syzbot]

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