uvm_fault: pool_do_put

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 36a555e0 Make udl(4) and uts(4) compile again in debug mod..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=120c51dce00000
kernel config: https://syzkaller.appspot.com/x/.config?x=26ca0a9c07f16a3a
dashboard link: https://syzkaller.appspot.com/bug?extid=720a6d95c22f58b2233a

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+720a6d...@syzkaller.appspotmail.com

uvm_fault(0xffffffff8261f558, 0xffff88513972d29a, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at pool_do_put+0x12e: movq 0x8(%rbx),%rbx


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[Anton Lindqvist]

#syz invalid