netbsd boot error: panic: out of memory before the pagedaemon thread exists

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 31b70387 make this compile without bio(4)
git tree: netbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=11e2ec3c900000
kernel config: https://syzkaller.appspot.com/x/.config?x=fab579639ba4bf0a
dashboard link: https://syzkaller.appspot.com/bug?extid=32e7d15376573d229960
compiler: g++ (Ubuntu 5.4.0-6ubuntu1~16.04.12) 5.4.0 20160609

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+32e7d1...@syzkaller.appspotmail.com

[ 2.7348621] panic: out of memory before the pagedaemon thread exists
[ 2.7348621] cpu0: Begin traceback...
[ 2.7463933] vpanic() at netbsd:vpanic+0x26f sys/kern/subr_prf.c:290
[ 2.7648572] snprintf() at netbsd:snprintf
[ 2.7848599] uvm_kick_pdaemon() at netbsd:uvm_kick_pdaemon
[ 2.8048581] uao_get() at netbsd:uao_get+0x8e5 sys/uvm/uvm_aobj.c:961
[ 2.8248595] uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c uvm_fault_lower_io sys/uvm/uvm_fault.c:2150 [inline]
[ 2.8248595] uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c uvm_fault_lower sys/uvm/uvm_fault.c:1927 [inline]
[ 2.8248595] uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c sys/uvm/uvm_fault.c:942
[ 2.8348563] uvm_fault_wire() at netbsd:uvm_fault_wire+0xaa sys/uvm/uvm_fault.c:2629
[ 2.8548558] uvm_map_pageable() at netbsd:uvm_map_pageable+0x91b sys/uvm/uvm_map.c:3481
[ 2.8748560] kcov_allocbuf.part.2() at netbsd:kcov_allocbuf.part.2+0x80
[ 2.8948566] kcov_remote_register() at netbsd:kcov_remote_register+0xa8 sys/kern/subr_kcov.c:265
[ 2.9248587] vhci_attach() at netbsd:vhci_attach+0x1b9 sys/dev/usb/vhci.c:1311
[ 2.9348560] config_attach_pseudo() at netbsd:config_attach_pseudo+0xc3 sys/kern/subr_autoconf.c:1670
[ 2.9548550] vhciattach() at netbsd:vhciattach+0xaf sys/dev/usb/vhci.c:1261
[ 2.9748557] config_finalize() at netbsd:config_finalize+0xb3 sys/kern/subr_autoconf.c:2175
[ 2.9948570] main() at netbsd:main+0x617 sys/kern/init_main.c:650
[ 3.0055374] cpu0: End traceback...
[ 3.0055374] fatal breakpoint trap in supervisor mode
[ 3.0055374] trap type 1 code 0 rip 0xffffffff80220a1d cs 0x8 rflags 0x286 cr2 0 ilevel 0 rsp 0xffffffff83473460
[ 3.0245934] curlwp 0xffffffff82efd180 pid 0.0 lowest kstack 0xffffffff8346c2c0
Stopped in pid 0.0 (system) at netbsd:breakpoint+0x5: leave
breakpoint() at netbsd:breakpoint+0x5
db_panic() at netbsd:db_panic+0x105 sys/ddb/db_panic.c:67
vpanic() at netbsd:vpanic+0x26f sys/kern/subr_prf.c:290
snprintf() at netbsd:snprintf
uvm_kick_pdaemon() at netbsd:uvm_kick_pdaemon
uao_get() at netbsd:uao_get+0x8e5 sys/uvm/uvm_aobj.c:961
uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c uvm_fault_lower_io sys/uvm/uvm_fault.c:2150 [inline]
uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c uvm_fault_lower sys/uvm/uvm_fault.c:1927 [inline]
uvm_fault_internal() at netbsd:uvm_fault_internal+0x2d9c sys/uvm/uvm_fault.c:942
uvm_fault_wire() at netbsd:uvm_fault_wire+0xaa sys/uvm/uvm_fault.c:2629
uvm_map_pageable() at netbsd:uvm_map_pageable+0x91b sys/uvm/uvm_map.c:3481
kcov_allocbuf.part.2() at netbsd:kcov_allocbuf.part.2+0x80
kcov_remote_register() at netbsd:kcov_remote_register+0xa8 sys/kern/subr_kcov.c:265
vhci_attach() at netbsd:vhci_attach+0x1b9 sys/dev/usb/vhci.c:1311
config_attach_pseudo() at netbsd:config_attach_pseudo+0xc3 sys/kern/subr_autoconf.c:1670
vhciattach() at netbsd:vhciattach+0xaf sys/dev/usb/vhci.c:1261
config_finalize() at netbsd:config_finalize+0xb3 sys/kern/subr_autoconf.c:2175
main() at netbsd:main+0x617 sys/kern/init_main.c:650
ds 4680
es 4680
fs 3440
gs 3490
rdi 5
rsi 0
--db_more--


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.