assert "swap" failed in uvm_pager.c

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4f07d5022fc4 ASSERT_DOUBLE_* test helpers
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=13e1c41a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=0cdd13d29306be482c62

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6b2447364c3d/disk-4f07d502.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/9d801fb8ab36/bsd-4f07d502.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0ccb2db31caa/kernel-4f07d502.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0cdd13...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "swap" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_pager.c", line 735
Starting stack trace...
panic(ffffffff833b07ef) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff833edb94,ffffffff83431872,2df,ffffffff83364bfa) at __assert+0x29 sys/kern/subr_prf.c:-1
uvm_aio_aiodone_pages(ffff80002a2463e0,0,1,0) at uvm_aio_aiodone_pages+0x4c4 sys/uvm/uvm_pager.c:745
uvm_aio_aiodone(fffffd806da36c28) at uvm_aio_aiodone+0x2c7 sys/uvm/uvm_pager.c:826
uvm_aiodone_daemon(ffff8000ffffc008) at uvm_aiodone_daemon+0x242 sys/uvm/uvm_pdaemon.c:371
end trace frame: 0x0, count: 252
End of stack trace.
syncing disks...45 40
done


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