8.0RC2 amd64 - kernel panic running make buildworld

Hi.

I installed 8.0RC2-amd64 on an 8-core opteron server a few days ago.

When I try to do a make buildworld or make buildkernel the server
reboots without any message left in the logs. The same happens
when building bigger ports (for example ruby18 or perl58)

With 8.0-RC2 debug flags and witness seem to be disabled in the
standard GENERIC kernel, so unfortunately it is not possible for me to
build a debug kernel without my server crashing..

Now my idea was to install the old 8.0-BETA4 and upgrade to RC2 through
makeworld + buildkernel (gdb+witness). But no luck. When trying to
upgrade to RC2 the 8.0-BETA4 also crashes. At least 8.0-BETA4 has debug
+ witness active in the GENERIC kernel..

So below some debug output of 8.0-BETA4 crashing. Has a vfs/ffs LOR
problem with the BETA4 already been fixed?

Does it make sense to send in a pr with the old 8.0-BETA4? 

BTW. I installed 7.2-STABLE on this same server and did a "make
buildworld" and "make buildkernel" which completed without any problem.

Cheers,
--Kai


----- make buildworld -j7 crash, freebsd 8.0-amd64-beta4 -----

lock order reversal:
 1st 0xffffff00073d5ba8 ufs (ufs)
_at_ /usr/src/sys/ufs/ffs/ffs_snapshot.c:423 2nd 0xffffff819d921558
bufwait (bufwait) _at_ /usr/src/sys/kern/vfs_bio.c:2559 3rd
0xffffff00070c19d0 ufs (ufs) _at_ /usr/src/sys/ufs/ffs/ffs_snapshot.c:544
KDB: stack backtrace: db_trace_self_wrapper() at
db_trace_self_wrapper+0x2a _witness_debugger() at _witness_debugger+0x2e
witness_checkorder() at witness_checkorder+0x81e
__lockmgr_args() at __lockmgr_args+0xcf3
ffs_lock() at ffs_lock+0x8c
VOP_LOCK1_APV() at VOP_LOCK1_APV+0x9b
_vn_lock() at _vn_lock+0x47
ffs_snapshot() at ffs_snapshot+0x1b9d
ffs_mount() at ffs_mount+0x666
vfs_donmount() at vfs_donmount+0xcde
nmount() at nmount+0x63
syscall() at syscall+0x1af
Xfast_syscall() at Xfast_syscall+0xe1
--- syscall (378, FreeBSD ELF64, nmount), rip = 0x8007b14fc, rsp =
0x7fffffffe9b8, rbp = 0x800902530 --- lock order reversal:
 1st 0xffffff819d921558 bufwait (bufwait)
_at_ /usr/src/sys/kern/vfs_bio.c:2559 2nd 0xffffff0007d9fa30 snaplk
(snaplk) _at_ /usr/src/sys/ufs/ffs/ffs_snapshot.c:793 KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
_witness_debugger() at _witness_debugger+0x2e
witness_checkorder() at witness_checkorder+0x81e
__lockmgr_args() at __lockmgr_args+0xcf3
ffs_lock() at ffs_lock+0x8c
VOP_LOCK1_APV() at VOP_LOCK1_APV+0x9b
_vn_lock() at _vn_lock+0x47
ffs_snapshot() at ffs_snapshot+0x1a6a
ffs_mount() at ffs_mount+0x666
vfs_donmount() at vfs_donmount+0xcde
nmount() at nmount+0x63
syscall() at syscall+0x1af
Xfast_syscall() at Xfast_syscall+0xe1
--- syscall (378, FreeBSD ELF64, nmount), rip = 0x8007b14fc, rsp =
0x7fffffffe9b8, rbp = 0x800902530 --- lock order reversal:
 1st 0xffffff0007d9fa30 snaplk (snaplk)
_at_ /usr/src/sys/kern/vfs_vnops.c:296 2nd 0xffffff00073d5ba8 ufs (ufs)
_at_ /usr/src/sys/ufs/ffs/ffs_snapshot.c:1587 KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
_witness_debugger() at _witness_debugger+0x2e
witness_checkorder() at witness_checkorder+0x81e
__lockmgr_args() at __lockmgr_args+0xcf3
ffs_snapremove() at ffs_snapremove+0xe7
softdep_releasefile() at softdep_releasefile+0x139
ufs_inactive() at ufs_inactive+0x1a5
vinactive() at vinactive+0x72
vput() at vput+0x230
vn_close() at vn_close+0x118
vn_closefile() at vn_closefile+0x5a
_fdrop() at _fdrop+0x23
closef() at closef+0x5b
kern_close() at kern_close+0x110
syscall() at syscall+0x1af
Xfast_syscall() at Xfast_syscall+0xe1
--- syscall (6, FreeBSD ELF64, close), rip = 0x80084cf9c, rsp =
0x7fffffffe9b8, rbp = 0 ---