panic: pmap_remove_ptes: unmanaged page marked PG_PVLIST: va ADDR, opte 0x2401

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 73556a19205d Use %b to format cpu flag info in dmesg, so w..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10678fbc980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=ab2c92eb8bae9c8ba938

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6103872e3732/disk-73556a19.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/9ec226c523d8/bsd-73556a19.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0f8b44d7f4ad/kernel-73556a19.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ab2c92...@syzkaller.appspotmail.com

panic: pmap_remove_ptes: unmanaged page marked PG_PVLIST: va 0x1b2ca37000, opte 0x2401
Starting stack trace...
panic(ffffffff828f7f44) at panic+0x16f sys/kern/subr_prf.c:229
pmap_remove_ptes(fffffd807eff41f0,fffffd80076346a0,7f800d965100,1b2ca20000,1b2ca60000,0,262dcbab5921cab) at pmap_remove_ptes+0x33e
pmap_do_remove(fffffd807eff41f0,1b2ca20000,1b2ca60000,0) at pmap_do_remove+0x410 sys/arch/amd64/amd64/pmap.c:1896
uvm_unmap_kill_entry_withlock(fffffd8008b96dc0,fffffd8068a93600,0) at uvm_unmap_kill_entry_withlock+0x1b1 sys/uvm/uvm_map.c:1897
uvm_map_teardown(fffffd8008b96dc0) at uvm_map_teardown+0x1c7 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:176 [inline]
uvm_map_teardown(fffffd8008b96dc0) at uvm_map_teardown+0x1c7 sys/uvm/uvm_map.c:2534
uvmspace_free(fffffd8008b96dc0) at uvmspace_free+0xa6 sys/uvm/uvm_map.c:3461
reaper(ffff80002a148cd8) at reaper+0x197 sys/kern/kern_exit.c:463
end trace frame: 0x0, count: 250
End of stack trace.


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