panic: kernel diagnostic assertion "bp->b_data != NULL" failed: file "/syzkaller/managers/main/kernel/sys/kern/vfs_biomem.c", line 235
Starting stack trace...
panic(ffffffff83379b6e) at panic+0x1ba sys/kern/subr_prf.c:229
__assert(ffffffff833b9cdd,ffffffff833763b6,eb,ffffffff83393421) at __assert+0x29 sys/kern/subr_prf.c:-1
buf_unmap(fffffd806b143e60) at buf_unmap+0x20a
buf_map(fffffd8069ca3d40) at buf_map+0x241 sys/kern/vfs_biomem.c:117
buf_get(fffffd806c7370e0,12e,4000) at buf_get+0x5be sys/kern/vfs_bio.c:1163
getblk(fffffd806c7370e0,12e,4000,0,ffffffffffffffff) at getblk+0x146 sys/kern/vfs_bio.c:-1
ffs2_balloc(fffffd806d0a0b00,4b8000,4000,fffffd8007bfd478,2,ffff80002a884c78) at ffs2_balloc+0x1778 sys/ufs/ffs/ffs_balloc.c:-1
ffs_write(ffff80002a884d00) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd806c7370e0,ffff80002a884eb8,7,fffffd8007bfd478) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806d0b1a60,ffff80002a884eb8,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff80002a84ca98,4,ffff80002a884eb8,0,ffff80002a884f60) at dofilewritev+0x242 sys/kern/sys_generic.c:380
sys_write(ffff80002a84ca98,ffff80002a885010,ffff80002a884f60) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80002a885010) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a885010) at syscall+0x962 sys/arch/amd64/amd64/trap.c:775
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xf9bdc5f1080, 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 e4c28bce-9379-8bb2-f2c8-a7cf484f58e0
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 0x000f26e0: 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 3.67
boot> show all pools
boot: illegal argument all
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace