[  95.6899179] panic: tcp_output
[  95.7014879] cpu0: Begin traceback...
[  95.7014879] vpanic() at netbsd:vpanic+0x214
[  95.7121758] snprintf() at netbsd:snprintf
[  95.7121758] tcp_output() at netbsd:tcp_output+0x4114
[  95.7233053] tcp_sendoob_wrapper() at netbsd:tcp_sendoob_wrapper+0x21e
[  95.7344327] sosend() at netbsd:sosend+0xa23
[  95.7455607] do_sys_sendmsg_so() at netbsd:do_sys_sendmsg_so+0x3c7
[  95.7567292] do_sys_sendmsg() at netbsd:do_sys_sendmsg+0x181
[  95.7691550] sys_sendmsg() at netbsd:sys_sendmsg+0xc4
[  95.7809925] sys___syscall() at netbsd:sys___syscall+0xe2
[  95.8012045] syscall() at netbsd:syscall+0x30e
[  95.8012045] --- syscall (number 198) ---
[  95.8145259] 6fe5e923f4aa:
[  95.8145259] cpu0: End traceback...

[  95.8234601] dumping to dev 4,1 (offset=0, size=0): not possible
[  95.8234601] rebooting...
SeaBIOS (version 1.8.2-20181029_212248-google)
Total RAM Size = 0x00000001e0000000 = 7680 MiB
CPUs found: 2     Max CPUs supported: 2
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 0x000f2a00: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304
Booting from Hard Disk 0...

>> NetBSD/x86 BIOS Boot, Revision 5.10 (Tue Jul 17 14:59:51 UTC 2018) (from NetBSD 8.0)
>> Memory: 639/3144640 k

     1. Boot normally
     2. Boot single user
     3. Disable ACPI
     4. Disable ACPI and SMP
     5. Drop to boot prompt