DragonFlyBSD

:Hi,
:
:during my recent work with the installer (add HAMMER support) my
:DragonFly box paniced while unmounting a HAMMER volume:
:
:panic: assertion: RB_EMPTY(&hmp->rb_inos_root) in hammer_free_hmp
:Trace beginning at frame 0xda299bf0
:panic(da299c14,1e,da287000,d270b958,da299c28) at panic+0x8c
:panic(c0532657,c0559b86,c051a96d,0,d270b958) at panic+0x8c
:hammer_free_hmp(d270bb60,d270b958,da299c6c,c032ae0d,d270b958) at
:hammer_free_hmp+0xd8
:hammer_vfs_unmount(d270b958,0,0,d270b978,1) at hammer_vfs_unmount+0x33
:dounmount(d270b958,0,d270b958,0,0) at dounmount+0x1a8
:sys_unmount(da299cf0,6,bd34,0,d270a518) at sys_unmount+0xdf
:syscall2(da299d40) at syscall2+0x1ef
:Xint0x80_syscall() at Xint0x80_syscall+0x36
:Debugger("panic")
:panic: from debugger
:Uptime: 17h54m57s

Here's the dmesg from your crash dump on leaf:

pid 20683 (dfuibe_installer), uid 0: exited on signal 11 (core dumped)
pid 20966 (dfuibe_installer), uid 0: exited on signal 11 (core dumped)
unmount(/mnt): Cannot unmount: 0 namecache references still present
unmount(/mnt): Cannot unmount: 2 process references still present
HAMMER: umount flushing..........................giving up
panic: assertion: RB_EMPTY(&hmp->rb_inos_root) in hammer_free_hmp
Trace beginning at frame 0xda299bf0

For some reason it was having a hard time flushing dirty inodes.

Could you tell if the disk drive was solid on while it was trying
    to umount?  There should have been about a 25-second delay (each
    '.' is one second, theoretically).

-Matt

Hope I got your question right. The disk is an additional VMWare disk
and was only used to test the installer. The procedure was to label the
disk, install DF on the HAMMER partition and let the installer unmount
it. Nothing special and no big load. The disk was idle most of the
time. Strange thing here was that this panic happened after about 10
slice/mount/install/unmount cycles. After a reboot of the VMWare VM it
worked again for about 10 test cycles.

Cheers

Matthias

:Hope I got your question right. The disk is an additional VMWare disk
:and was only used to test the installer. The procedure was to label the
:disk, install DF on the HAMMER partition and let the installer unmount
:it. Nothing special and no big load. The disk was idle most of the
:time. Strange thing here was that this panic happened after about 10
:slice/mount/install/unmount cycles. After a reboot of the VMWare VM it
:worked again for about 10 test cycles.
:
:Cheers
:
: Matthias

Very odd.  Try w/ the lastest master.  It has this patch:

http://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/d40bfeca35caa9f1c470a05381618447b19746c9

Which I hope solves the umount issue.  If not we will have to
    investigate more.

-Matt
                    Matthew Dillon 
                    <dillon@backplane.com>

No luck. VM crashed after the first install cycle. Backtrace stays the
same:

#0 dumpsys () at ./machine/thread.h:83
#1 0xc02e21ee in boot (howto=260) at
/build/src/sys/kern/kern_shutdown.c:376
#2 0xc02e230f in panic (fmt=0xc053c516 "from debugger") at
/build/src/sys/kern/kern_shutdown.c:801
#3 0xc0165705 in db_panic (addr=-1068660116, have_addr=0, count=-1,
modif=0xd9965aa0 "") at /build/src/sys/ddb/db_command.c:447
#4 0xc0165d70 in db_command_loop () at
/build/src/sys/ddb/db_command.c:343
#5 0xc0168344 in db_trap (type=3, code=0) at
/build/src/sys/ddb/db_trap.c:71
#6 0xc04d8bbf in kdb_trap (type=3, code=0, regs=0xd9965b98) at
/build/src/sys/platform/pc32/i386/db_interface.c:148
#7 0xc04ea425 in trap (frame=0xd9965b98) at
/build/src/sys/platform/pc32/i386/trap.c:815
#8 0xc04d98d7 in calltrap () at
/build/src/sys/platform/pc32/i386/exception.s:785
#9 0xc04d8a6c in Debugger (msg=0xc0552b61 "panic") at
./cpu/cpufunc.h:73
#10 0xc02e2306 in panic (fmt=0xc0538b37 "assertion: %s in %s") at
/build/src/sys/kern/kern_shutdown.c:799
#11 0xc0463079 in hammer_free_hmp (mp=0xd270cfd8) at
/build/src/sys/vfs/hammer/hammer_vfsops.c:715
#12 0xc04631a2 in hammer_vfs_unmount (mp=0xd270cfd8, mntflags=0) at
/build/src/sys/vfs/hammer/hammer_vfsops.c:663
#13 0xc033087d in dounmount (mp=0xd270cfd8, flags=0) at
/build/src/sys/kern/vfs_syscalls.c:701
#14 0xc0330ace in sys_unmount (uap=0xd9965cf0) at
/build/src/sys/kern/vfs_syscalls.c:586
#15 0xc04e9dc5 in syscall2 (frame=0xd9965d40) at
/build/src/sys/platform/pc32/i386/trap.c:1357
#16 0xc04d9986 in Xint0x80_syscall () at
/build/src/sys/platform/pc32/i386/exception.s:876

The crash dump is available at:
http://www.mathematik.uni-marburg.de/~schmidtm/crash/ but I'm not sure if it
contains any new information.

Cheers

Matthias

Matthias,
I installed my VM under VMware HAMMER-only without noticing this problem.
How can I reproduce it?