DragonFlyBSD

I got the following panic on a recent master:

DragonFly rama 2.9-DEVELOPMENT DragonFly v2.9.1.1083.g90d6d7-DEVELOPMENT #35: Sun Apr 10 21:13:25 HST 2011 root@rama:/usr/obj/usr/src/sys/RAMA i386

fs = ?i?K??S?7| {?v????px]2?
?W?L
???|)?)
panic: ffs_sync: rofs mod

(kgdb) bt
#0 _get_mycpu (di=0xc072e780) at ./machine/thread.h:79
#1 md_dumpsys (di=0xc072e780) at /usr/src/sys/platform/pc32/i386/dump_machdep.c:264
#2 0xc01bbf28 in dumpsys () at /usr/src/sys/kern/kern_shutdown.c:893
#3 0xc01bc535 in boot (howto=<value optimized out>) at /usr/src/sys/kern/kern_shutdown.c:388
#4 0xc01bc79a in panic (fmt=0xc045621c "ffs_sync: rofs mod") at /usr/src/sys/kern/kern_shutdown.c:799
#5 0xc02e8a6b in ffs_sync (mp=0xdd74b460, waitfor=6) at /usr/src/sys/vfs/ufs/ffs_vfsops.c:977
#6 0xc022fdf1 in vfs_sync (mp=0xdd74b460, waitfor=6) at /usr/src/sys/kern/vfs_vfsops.c:196
#7 0xc02250fc in sync_fsync (ap=0xd9c6bd2c) at /usr/src/sys/kern/vfs_sync.c:439
#8 0xc022f187 in vop_fsync (ops=0xc06b8300, vp=0xd9cbfab8, waitfor=4, flags=0) at /usr/src/sys/kern/vfs_vopops.c:540
#9 0xc0224fef in syncer_thread () at /usr/src/sys/kern/vfs_sync.c:234
#10 0xc01acbe1 in suspend_kproc (td=Cannot access memory at address 0x8
) at /usr/src/sys/kern/kern_kthread.c:187
Backtrace stopped: previous frame inner to this frame (corrupt stack?)

kernel and vmcore available at:
http://www.theshell.com/~pavalos/crash/crash16.tar.xz

--Peter