[ 1911.8599914] panic: kernel diagnostic assertion "mutex_owned(pipe->pipe_lock)" failed: file "/syzkaller/managers/netbsd/kernel/sys/kern/sys_pipe.c", line 371 
[[ 1 9119111..8784794393919]1 ]W AcpRuNI0N: G:B eSgPinL  NtOrTa ceLObaWEcRkE.D. .O
[
 1911.8749391] N SYSCALL 0 -1542256 EXIT fvp71a1n7ic07(0)  7at
[ [1 9191111..88774949339911]]   WARNING: SnPLet NbOsTd :LvOpWaEnRiEc+D0 OxN2 SYSC1A4L
[
 1911.8749391] L 0 -9920576 EXIT c00106b0 7
[ 1911.8749391] _GLOBAL__sub_D_65535_0_cpu_configure() at netbsd:_GLOBAL__sub_D_65535_0_cpu_configure
[ 1911.8749391] pipelock() at netbsd:pipelock+0xb0
[ 1911.8749391] pipe_write() at netbsd:pipe_write+0x99
[ 1911.8749391] dofilewrite() at netbsd:dofilewrite+0x1b7
[ 1[ 911911.18.784794399319]1 s] yWsA_wRNrIiNtGe(: )S PaLt  NOT LOWERneEDt bsONd :SsYySsC_wArLLi t6e+0 0x3 7E8
X[
 1911.8749391] IT 0 7
[ 1911.8749391] WARNING: SPL NOT LOWERED sOyNs cTRaAllP( E) XaItT  6 0
[ 1911.8749391] [W A19R1NI1.NG87: 4S9PL3 91NO] T nLetObWsERd:EsDy sONc alTRlA+0Px E3X2Ie
T
[ [1 9191111..8784749933919]1]   -6- -0 
[
 1[ 911911.18.748974399139] 1]sy sWAcaRNlIlN G(:nu mSbPLer N 4OT)  L--OW-
E[
 1911.8749391] RED ON 7T2RAe0Pa E7cXI3Te0 2a6: [
 [1 91191.118.7847493939911] ] 0c
[ [1 1919111.8.7874499339911] ] pWuA0R:N EInNdG :t SrPacLe bNaOcT kL..OW.
[ 1
911
.
87[4 91931911]. 8E74R9ED39 O1N]  TduRmApP iEngXI tTo 6  d0e
v
[ 1911.8749391]  4,1 (offset=0, size=0): not possible
[ 1911.8749391] rebooting...
SeaBIOS (version 1.8.2-20190322_093631-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 0x000f29c0: 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