panic: thread NUM p_stat is NUM (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4cd34baf9f06 add more AMD "Krackan Point" device ids
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=17c8142e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=39fb0d2c2137c688a8f4

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/afc04160cc28/disk-4cd34baf.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/c16b14a6eec2/bsd-4cd34baf.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/344f12b47c6e/kernel-4cd34baf.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+39fb0d...@syzkaller.appspotmail.com

panic: thread 0 p_stat is 48
Starting stack trace...
panic(ffffffff83508288) at panic+0x1ba sys/kern/subr_prf.c:229
wakeup_n(ffffffff839b0730,ffffffff) at wakeup_n+0x3af
softintr_dispatch(0) at softintr_dispatch+0xf9 sys/kern/kern_softintr.c:87
dosoftint(0) at dosoftint+0x48 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
end of kernel
end trace frame: 0x7e7738f328d0, count: 252
End of stack trace.
syncing disks...panic: thread 1869903203 p_stat is 101
Starting stack trace...
panic(ffffffff83508288) at panic+0x1ba sys/kern/subr_prf.c:229
wakeup_n(ffff80000002c000,1) at wakeup_n+0x3af
task_add(ffff80000002c000,ffff8000002a24d8) at task_add+0x15a sys/kern/kern_task.c:372
ifiq_input(ffff8000002a2490,ffff80003c8fef50) at ifiq_input+0x4af sys/net/ifq.c:784
vio_rxeof(ffff80000002fc00) at vio_rxeof+0x429 sys/dev/pv/if_vio.c:1626
vio_rx_intr(ffff8000002a3000) at vio_rx_intr+0x98 sys/dev/pv/if_vio.c:1642
intr_handler(ffff80003c8ff090,ffff8000002a1600) at intr_handler+0xcb sys/arch/amd64/amd64/intr.c:-1
Xintr_ioapic_edge25_untramp() at Xintr_ioapic_edge25_untramp+0x18f
Xspllower() at Xspllower+0x1d
tsleep_nsec(ffffffff83a5f2c0,4,ffffffff8350ab13,ffffffffffffffff) at tsleep_nsec+0x197 sys/kern/kern_synch.c:148
uvn_io(fffffd806f5444b8,ffff80003c8ff400,1,31,1) at uvn_io+0x765 sys/uvm/uvm_vnode.c:1281
uvn_put(fffffd806f5444b8,ffff80003c8ff400,1,31) at uvn_put+0x125 sys/uvm/uvm_vnode.c:891
uvm_pager_put(fffffd806f5444b8,fffffd80072c3000,ffff80003c8ff4a0,ffff80003c8ff4c4,31,0,633f1129479fe3e4) at uvm_pager_put+0x10a sys/uvm/uvm_pager.c:505
uvn_flush(fffffd806f5444b8,0,0,31) at uvn_flush+0x68d sys/uvm/uvm_vnode.c:705
uvm_vnp_sync(ffff800000c68400) at uvm_vnp_sync+0x1e7 sys/uvm/uvm_vnode.c:1501
sys_sync(ffff80002a7d2d28,0,0) at sys_sync+0xd4 sys/kern/vfs_syscalls.c:534
vfs_syncwait(ffff80002a7d2d28,1) at vfs_syncwait+0x44 sys/kern/vfs_subr.c:-1
vfs_shutdown(ffff80002a7d2d28) at vfs_shutdown+0x97 sys/kern/vfs_subr.c:1803
boot(100) at boot+0x166 sys/arch/amd64/amd64/machdep.c:931
reboot(100) at reboot+0xa8
panic(ffffffff83508288) at panic+0x1e3
wakeup_n(ffffffff839b0730,ffffffff) at wakeup_n+0x3af
softintr_dispatch(0) at softintr_dispatch+0xf9 sys/kern/kern_softintr.c:87
dosoftint(0) at dosoftint+0x48 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
end of kernel
end trace frame: 0x7e7738f328d0, count: 232
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 e4c28bce-9379-8bb2-f2c8-a7cf484f58e0
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 0x000f2600: 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 3.67
boot> set $lines = 0
set: syntax error
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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