DragonFlyBSD

On an i386 SMP system (b373db6a1) I got this panic:

#0 _get_mycpu () at ./machine/thread.h:79
#1 md_dumpsys (di=0xc0755700)
at /usr/src/sys/platform/pc32/i386/dump_machdep.c:266
#2 0xc01accde in dumpsys () at /usr/src/sys/kern/kern_shutdown.c:913
#3 0xc01ad2f4 in boot (howto=<optimized out>)
at /usr/src/sys/kern/kern_shutdown.c:373
#4 0xc01ad564 in panic (
fmt=0xc03b923c "assertion \"%s\" failed in %s at %s:%u")
at /usr/src/sys/kern/kern_shutdown.c:819
#5 0xc01b8374 in dfly_schedulerclock (lp=<unavailable>, period=286364,
cpstamp=2464609796) at /usr/src/sys/kern/usched_dfly.c:720
#6 0xc01b427b in usched_schedulerclock (lp=0xd59ec500, periodic=286364,
time=2464609796) at /usr/src/sys/kern/kern_usched.c:158
#7 0xc018c0c7 in schedclock (info=0xff80ad18, in_ipi=1, frame=0x0)
at /usr/src/sys/kern/kern_clock.c:778
#8 0xc01ab882 in systimer_intr (timep=0xc0888db8, in_ipi=1, frame=0x0)
at /usr/src/sys/kern/kern_systimer.c:100
---Type <return> to continue, or q <return> to quit---
#9 0xc01bdc1c in lwkt_process_ipiq_core (sgd=<optimized out>,
ip=0xc461a40c, frame=<optimized out>)
at /usr/src/sys/kern/lwkt_ipiq.c:668
#10 0xc01bddec in lwkt_process_ipiq ()
at /usr/src/sys/kern/lwkt_ipiq.c:494
#11 0xc01bdf33 in lwkt_wait_ipiq (target=0xff800000, seq=869270)
at /usr/src/sys/kern/lwkt_ipiq.c:427
#12 0xc01ca1fe in callout_stop (c=0xc0888dd0)
at /usr/src/sys/kern/kern_timeout.c:488
#13 0xc01ca46f in callout_reset (c=0xc0888dd0, to_ticks=10,
ftn=0xc03a42c7 <sysbeepstop>, arg=0x0)
at /usr/src/sys/kern/kern_timeout.c:361
#14 0xc03a4b1a in sysbeep (pitch=2982, period=10)
at /usr/src/sys/platform/pc32/isa/clock.c:483
#15 0xc0360a40 in sc_bell (scp=<unavailable>, pitch=<unavailable>,
duration=10) at /usr/src/sys/dev/misc/syscons/syscons.c:3792
#16 0xc03626bb in scioctl (ap=0xd96f6b54)
---Type <return> to continue, or q <return> to quit---
at /usr/src/sys/dev/misc/syscons/syscons.c:1228
#17 0xc018dfc2 in dev_dioctl (dev=0xd5b12420, cmd=536890120,
data=0xd96f6c08 <error reading variable>, fflag=7, cred=0xd688ae60,
msg=0xd96f6cf0) at /usr/src/sys/kern/kern_device.c:243
#18 0xc02b9a90 in devfs_fo_ioctl (fp=0xd90177c8, com=536890120,
data=0xd96f6c08 <error reading variable>, ucred=0xd688ae60,
msg=0xd96f6cf0) at /usr/src/sys/vfs/devfs/devfs_vnops.c:1446
#19 0xc01de9f8 in fo_ioctl (fp=0xd90177c8, com=536890120,
data=0xd96f6c08 <error reading variable>, cred=0xd688ae60,
msg=0xd96f6cf0) at /usr/src/sys/sys/file2.h:88
#20 0xc01deed3 in mapped_ioctl (fd=5, com=536890120,
uspc_data=0x640ba6 <Address 0x640ba6 out of bounds>, map=0x0,
msg=0xd96f6cf0) at /usr/src/sys/kern/sys_generic.c:733
#21 0xc01def82 in sys_ioctl (uap=0xd96f6cf0)
at /usr/src/sys/kern/sys_generic.c:552
#22 0xc039d99c in syscall2 (frame=0xd96f6d40)
at /usr/src/sys/platform/pc32/i386/trap.c:1321
---Type <return> to continue, or q <return> to quit---
#23 0xc036c4f6 in Xint0x80_syscall ()
at /usr/src/sys/platform/pc32/i386/exception.s:878
#24 0x0000001f in ?? ()