panic: pmap_remove_ptes: unmanaged page marked PG_PVLIST: va ADDR, opte 0x3edff

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a6de02d933e6 spelling
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=144b11a5980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=3d909086edcb6137cf06

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e4ec44b4ec4/disk-a6de02d9.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/44d7af2f215d/bsd-a6de02d9.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/39d6dea1b4e4/kernel-a6de02d9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3d9090...@syzkaller.appspotmail.com

panic: pmap_remove_ptes: unmanaged page marked PG_PVLIST: va 0x1b2de60000, opte 0x3edff
Starting stack trace...
panic(ffffffff8306b6fa) at panic+0x1d0 sys/kern/subr_prf.c:229
pmap_remove_pte(fffffd8069d9a5e0,fffffd800818af60,7f800d96f300,1b2de60000,1b2e000000,0) at pmap_remove_pte
pmap_do_remove(fffffd8069d9a5e0,1b2de60000,1b2e220000,0) at pmap_do_remove+0x533 sys/arch/amd64/amd64/pmap.c:1909
uvm_unmap_kill_entry_withlock(fffffd80749bd6f0,fffffd8062ba6400,0) at uvm_unmap_kill_entry_withlock+0x274 sys/uvm/uvm_map.c:1883
uvm_map_teardown(fffffd80749bd6f0) at uvm_map_teardown+0x267 sys/uvm/uvm_map.c:2520
uvmspace_free(fffffd80749bd6f0) at uvmspace_free+0xe8 sys/uvm/uvm_map.c:3447
reaper(ffff800029fd91c0) at reaper+0x25b sys/kern/kern_exit.c:480
end trace frame: 0x0, count: 250
End of stack trace.


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