kern/57281: panic wscons vcons_intr ?

[prlw1%cam.ac.uk@localhost]

>Number:         57281
>Category:       kern
>Synopsis:       panic wscons vcons_intr ?
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Mar 21 19:55:01 +0000 2023
>Originator:     Patrick Welche
>Release:        17 March 2023 -current src
>Organization:
>Environment:
NetBSD-10.99.2/amd64
>Description:
Laptop suddenly panicked. The only non idle processes were

PID    LID S CPU     FLAGS       STRUCT LWP *               NAME WAIT
0    > 189 7   0       240   ffff960cce24c040            ioflush
0    >  27 7   1       200   ffff960ccd156680          softclk/1

dmesg:
[ 10466.4348600] fatal page fault in supervisor mode
[ 10466.4348600] trap type 6 code 0x2 rip 0xffffffff80814d19 cs 0x8 rflags 0x102
82 cr2 0xffffa30031307be0 ilevel 0x8 rsp 0xffffa30433b6af20
[ 10466.4348600] curlwp 0xffff960ccd156680 pid 0.27 lowest kstack 0xffffa30433b662c0
[ 10466.4348600] panic: trap
[ 10466.4348600] cpu1: Begin traceback...
[ 10466.4348600] vpanic() at netbsd:vpanic+0x177
[ 10466.4348600] panic() at netbsd:panic+0x3c
[ 10466.4348600] trap() at netbsd:trap+0xa9f
[ 10466.4348600] --- trap (number 6) ---
[ 10466.4348600] callout_softclock() at netbsd:callout_softclock+0x149
[ 10466.4348600] softint_dispatch() at netbsd:softint_dispatch+0x8f
[ 10466.4348600] DDB lost frame for netbsd:Xsoftintr+0x4c, trying 0xffffa30433b6aff0
[ 10466.4348600] Xsoftintr() at netbsd:Xsoftintr+0x4c
[ 10466.4348600] --- interrupt ---
[ 10466.4348600] ?() at ffffa30433b6b000
[ 10466.4348600] ostype() at ffffffff80c19a88
[ 10466.4348600] cpu1: End traceback...

(gdb) thread apply all bt

Thread 2.1 (<kvm>):
#0  0xffffffff80233855 in cpu_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at ../../../../arch/amd64/amd64/machdep.c:717
#1  0xffffffff807fd3bb in kern_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at ../../../../kern/kern_reboot.c:73
#2  0xffffffff80832f27 in vpanic (fmt=fmt@entry=0xffffffff80b92330 "trap", ap=ap@entry=0xffffa30433b6ace8) at ../../../../kern/subr_prf.c:291
#3  0xffffffff80832ffc in panic (fmt=fmt@entry=0xffffffff80b92330 "trap") at ../../../../kern/subr_prf.c:208
#4  0xffffffff80235ed5 in trap (frame=0xffffa30433b6ae30) at ../../../../arch/amd64/amd64/trap.c:326
#5  0xffffffff8022ed35 in alltraps ()
#6  0xffff9610284d0340 in ?? ()
#7  0xffffa30031307be0 in ?? ()
#8  0xffffa30031307be0 in ?? ()
#9  0x00007f7ff76ad000 in ?? ()
#10 0x0500000000000000 in ?? ()
#11 0x0500000000000000 in ?? ()
#12 0xffff960ccd4fcb40 in ?? ()
#13 0xffff960ccdec2ec8 in ?? ()
#14 0xffffffff80e691c0 in sleepq_locks ()
#15 0xffffffff80800d3a in sched_resched_cpu (ci=0xffffffff807083e2 <vcons_intr>, pri=<optimized out>, unlock=<optimized out>) at ../../../../kern/kern_runq.c:387
#16 0xffffffff808083de in softint_execute (s=2, l=0xffff960ccd156680) at ../../../../kern/kern_softint.c:595
#17 softint_dispatch (pinned=<optimized out>, s=2) at ../../../../kern/kern_softint.c:840
#18 0xffffffff8022ea8c in Xsoftintr ()
#19 0x604d51c132dbf4e8 in ?? ()
#20 0x600d51813299f4a8 in ?? ()
Backtrace stopped: Cannot access memory at address 0xffffa30433b6b000




>How-To-Repeat:
Nothing in particular was happening. Laptop has been perfectly stable.
>Fix: