Assert on shutdown

[coypu%SDF.ORG@localhost]

In case this is interesting.
I'm not sure if I can reproduce it yet

acpibut0: power button pressed, shutting down!
syncing disks... 4 done
unmounted /dev/sd2a on /mnt type msdos
unmounted tmpfs on /var/shm type tmpfs
unmounted procfs on /proc type procfs
unmounted kernfs on /kern type kernfs
sd0: detached
scsibus0: detached
cd0: detached
atapibus0: detached
audio0: detached
atabus1: detached
pci6: detached
pci5: detached
pci2: detached
sysbeep0: detached
midi0: detached
ppb5: detached
ppb4: detached
ppb1: detached
audio1: detached
forcefully unmounted ptyfs on /dev/pts type ptyfs
forcefully unmounted tmpfs on /tmp type tmpfs
Skipping crash dump on recursive panic
panic: kernel diagnostic assertion "offset != 0 && offset < softint_bytes" failed: file "/usr/src/sys/kern/kern_softint.c", line 484 0 8192
cpu0: Begin traceback...
vpanic() at netbsd:vpanic+0x140
cd_play_msf() at netbsd:cd_play_msf
softint_schedule() at netbsd:softint_schedule+0x7e
audio_pint() at netbsd:audio_pint+0x39e
hdafg_stream_intr() at netbsd:hdafg_stream_intr+0xc2
hdaudio_intr() at netbsd:hdaudio_intr+0x9e
Xintr_ioapic_level4() at netbsd:Xintr_ioapic_level4+0xf2
--- interrupt ---
x86_pause() at netbsd:x86_pause+0x2
sleepq_block() at netbsd:sleepq_block+0x1c5
cv_timedwait_sig() at netbsd:cv_timedwait_sig+0x107
ttysleep() at netbsd:ttysleep+0x7c
ttread() at netbsd:ttread+0x296
cdev_read() at netbsd:cdev_read+0x70
spec_read() at netbsd:spec_read+0xc3
VOP_READ() at netbsd:VOP_READ+0x37
vn_read() at netbsd:vn_read+0x94
dofileread() at netbsd:dofileread+0x8f
sys_read() at netbsd:sys_read+0x5f
syscall() at netbsd:syscall+0x15b
--- syscall (number 3) ---
7db7c203da7a:
cpu0: End traceback...
rebooting...
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