uvm_fault: refcnt_rele

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c16771e8b440 repeat less and distinguish beteen format and..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=175847e4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=be9fede29e7b9e3a6d29

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/da9683821bab/disk-c16771e8.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/c0af71b09469/bsd-c16771e8.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4f65547f8837/kernel-c16771e8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+be9fed...@syzkaller.appspotmail.com

uvm_fault(0xffffffff83985b50, 0x588fe028, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at refcnt_rele+0x158: movq 0(%rax,%r12,8),%r12
TID PID UID PRFLAGS PFLAGS CPU COMMAND
509585 13229 0 0x2 0x1 1 syz-executor
*473449 16638 0 0x14000 0x200 0 reaper
refcnt_rele(fffffd807f7d2340) at refcnt_rele+0x158 sys/kern/kern_synch.c:935
crfree(fffffd807f7d2340) at crfree+0x35 sys/kern/kern_prot.c:971
reaper(ffff80002a2f8f68) at reaper+0xba proc_free sys/kern/kern_exit.c:431 [inline]
reaper(ffff80002a2f8f68) at reaper+0xba sys/kern/kern_exit.c:471
end trace frame: 0x0, count: 12
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[syzbot]

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