panic: kernel diagnostic assertion "bp->b_data != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/vfs_biomem.c", line 235
Starting stack trace...
panic(ffffffff829555dd) at panic+0x16f sys/kern/subr_prf.c:229
__assert(ffffffff82908f1c,ffffffff828a9220,eb,ffffffff8288ebc2) at __assert+0x29 sys/kern/subr_prf.c:157
buf_unmap(fffffd80659e7c08) at buf_unmap+0x1a8 sys/kern/vfs_biomem.c:235
buf_map(fffffd8074fddd60) at buf_map+0x1e6 sys/kern/vfs_biomem.c:117
buf_get(fffffd805ac2b288,1,4000) at buf_get+0x459 sys/kern/vfs_bio.c:1175
getblk(fffffd805ac2b288,1,4000,0,ffffffffffffffff) at getblk+0xfd sys/kern/vfs_bio.c:1044
ffs2_balloc(fffffd806bb49bb8,4000,4000,fffffd807f7d7410,0,ffff8000357be588) at ffs2_balloc+0x685 sys/ufs/ffs/ffs_balloc.c:539
ffs_write(ffff8000357be610) at ffs_write+0x3c7 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd805ac2b288,ffff8000357be830,1,fffffd807f7d7410) at VOP_WRITE+0xc3 sys/kern/vfs_vops.c:245
vn_write(fffffd8071649850,ffff8000357be830,1) at vn_write+0x1a4 sys/kern/vfs_vnops.c:408
dofilewritev(ffff80002a157760,5,ffff8000357be830,1,ffff8000357be8f0) at dofilewritev+0x1a9 sys/kern/sys_generic.c:375
sys_pwritev(ffff80002a157760,ffff8000357be9a0,ffff8000357be8f0) at sys_pwritev+0xb6 sys/kern/vfs_syscalls.c:3360
syscall(ffff8000357be9a0) at syscall+0x8cf mi_syscall sys/sys/syscall_mi.h:180 [inline]
syscall(ffff8000357be9a0) at syscall+0x8cf sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xb9748ab7310, count: 243
End of stack trace.
syncing disks...34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34  giving up

dump to dev 4,1 not possible
rebooting...
SeaBIOS (version 1.8.2-google)
Total RAM Size = 0x0000000080000000 = 2048 MiB
CPUs found: 2     Max CPUs supported: 2
SeaBIOS (version 1.8.2-google)
Machine UUID 69eb9058-0362-23fd-9d6a-f99e4488aea0
found virtio-scsi at 0:3
virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0
virtio-scsi blksize=512 sectors=4194304 = 2048 MiB
drive 0x000f27f0: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304
Sending Seabios boot VM event.
Booting from Hard Disk 0...
>> OpenBSD/amd64 BOOT 3.65
boot> show malloc
boot: illegal argument malloc
boot> show all pools
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace