panic: uvm_fault(ADDR, 0x47, NUM, NUM) -> e

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1175e773e1a3 sadly attach functions cannot indicate failur..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=11865e7a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=c145506efa0417d8751d

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5e07d397ffe8/disk-1175e773.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/07fdf85110c0/bsd-1175e773.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/79091c6c65a6/kernel-1175e773.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c14550...@syzkaller.appspotmail.com

panic: init died (signal 0, exit 10)
Starting stack trace...
panic(ffffffff834d35c6) at panic+0x1d0 sys/kern/subr_prf.c:229
exit1(ffff8000fffffc88,a,0,1) at exit1+0x128 sys/kern/kern_exit.c:135
sys_exit(ffff8000fffffc88,ffff80002a1acbc0,ffff80002a1acb10) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80002a1acbc0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a1acbc0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x772accd0aff0, count: 252
End of stack trace.
syncing disks...WARNING: SPvLm_ NultLOxffEDe ON 800SYbSCAL3L5 88,3 9x4985504 2E)X -> 0 e
3
faStopped at savectx+0xae: movl $0,%gs:0x688
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*334553 79677 0 0 0x4000000 1 syz-executor
363429 1 0 0x30080002 0x2000 0K init
savectx() at savectx+0xae
end of kernel
end trace frame: 0x46320f0bef0, count: 14
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports. Insufficient info makes it difficult to find and fix bugs.
ddb{1}>
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
*cpu0: uvm_fault(0xffffef800b063d58, 0x47, 0, 2) -> e
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0x46320f0bef0, count: -1
ddb{1}>


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