panic: assertion: leaf->base.obj_id == ip->obj_id in hammer_ip_delete_range

[YONETANI Tomokazu]

Hi.
I'm still seeing this panic, although very occasionally, during bulkbuild.
It's a DELL PowerEdge with Core 2 Duo and 2G bytes of RAM, running
an SMP x86_64 kernel built from source as of c652b.  The HAMMER filesystem
is version 4 (originally version 2 but migrated to version 4 later), has
never been filled up, and about 40% is in use.  I have
`daily_clean_hammer_enable="NO"' in /etc/periodic.conf and occasionally run
`hammer cleanup /pfs/*', so no cleanup should be involved at the time of
panic.  I happened to be running two instances of hammer command at that
time, one for iostats and another for bstats, but I'm not sure it's anything
to do with the panic because I remember seeing the panic without those
commands running.

The backtrace looks almost the same as that of i386 version, but I can
upload the dump on leaf tomorrow if you think it's worth looking at it.

Cheers.