panic: trap type NUM, code=NUM, pc=NUM (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8db72fe4e92e Enable acpiac(4) and acpibat(4).
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=157aa59f080000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=7179cdce79209678649c

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+7179cd...@syzkaller.appspotmail.com

panic: trap type 6, code=10, pc=0
Starting stack trace...
panic(ffffffff8256feb0) at panic+0x155 sys/kern/subr_prf.c:229
kerntrap(ffff8000298b6570) at kerntrap+0x1b7 sys/arch/amd64/amd64/trap.c:313
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
0(fffffd8075541f00,fffffd8075541f00,80004c00,fffffd8075541f00,0,0) at 0
softclock_process_tick_timeout(fffffd8075541f00,0) at softclock_process_tick_timeout+0x1ac sys/kern/kern_timeout.c:725
softclock(0) at softclock+0x11a sys/kern/kern_timeout.c:756
softintr_dispatch(0) at softintr_dispatch+0xd1 sys/arch/amd64/amd64/softintr.c:90
Xsoftclock() at Xsoftclock+0x1f
x2apic_readreg(390) at x2apic_readreg+0x2a sys/arch/amd64/amd64/lapic.c:141
lapic_delay(3e8) at lapic_delay+0xb1 lapic_gettick sys/arch/amd64/amd64/lapic.c:398 [inline]
lapic_delay(3e8) at lapic_delay+0xb1 sys/arch/amd64/amd64/lapic.c:617
pckbc_poll_cmd1(ffff800000024300,0,ffff8000298b6920) at pckbc_poll_cmd1+0x285 pckbc_poll_data1 sys/dev/ic/pckbc.c:148 [inline]
pckbc_poll_cmd1(ffff800000024300,0,ffff8000298b6920) at pckbc_poll_cmd1+0x285 sys/dev/ic/pckbc.c:612
pckbc_poll_cmd(ffff800000024300,0,ffff8000298b69df,1,0,0,cbfda1cebb257089) at pckbc_poll_cmd+0xf6 sys/dev/ic/pckbc.c:684
pckbd_enable(ffff800000683780,1) at pckbd_enable+0xc0 sys/dev/pckbc/pckbd.c:463
wskbdopen(4300,21,2000,ffff80002172c550) at wskbdopen+0x1fa wskbd_enable sys/dev/wscons/wskbd.c:785 [inline]
wskbdopen(4300,21,2000,ffff80002172c550) at wskbdopen+0x1fa wskbd_do_open sys/dev/wscons/wskbd.c:861 [inline]
wskbdopen(4300,21,2000,ffff80002172c550) at wskbdopen+0x1fa sys/dev/wscons/wskbd.c:843
spec_open(ffff8000298b6af8) at spec_open+0x3df sys/kern/spec_vnops.c:150
VOP_OPEN(fffffd80677cccc8,21,fffffd807f7d79c0,ffff80002172c550) at VOP_OPEN+0x6c sys/kern/vfs_vops.c:138
vn_open(ffff8000298b6d48,21,0) at vn_open+0x467 sys/kern/vfs_vnops.c:177
doopenat(ffff80002172c550,ffffff9c,20000000,20,0,ffff8000298b6f30) at doopenat+0x26a sys/kern/vfs_syscalls.c:1127
syscall(ffff8000298b6fa0) at syscall+0x447 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xc27ae9401e0, count: 237
End of stack trace.

dump to dev 4,1 not possible
rebooting...
SeaBIOS (version 1.8.2-google)
Total RAM Size = 0x0000000080000000 = 2048 MiB
CPUs found: 2 Max CPUs supported: 2
SeaBIOS (version 1.8.2-google)
Machine UUID 7bbb59a4-3b4e-2ed3-58f8-154d5cc405f8
found virtio-scsi at 0:3
virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0
virtio-scsi blksize=512 sectors=4194304 = 2048 MiB
drive 0x000f24c0: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304
Sending Seabios boot VM event.
Booting from Hard Disk 0...
>> OpenBSD/amd64 BOOT 3.55
boot> set $maxwidth = 0
set: syntax error
boot> show panic
boot: illegal argument panic
boot> trace
boot> show registers
boot> show proc
boot> ps
boot> show all locks
boot> show malloc
boot> show all pools
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace


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[syzbot]

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