[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: (ITS#6021) slapo-pcache/back-ldap slapd crashes



toby@inf.ed.ac.uk wrote:
> OK, this is my first crash since moving to 2.4.16:
>
> Slightly different from the previous ones, but is coming through
> pcache.c:remove_from_template and, according to slapd log, was
> removing queries from cache when crash occurred:
>
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 5
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 26
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 4
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 25
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 3
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 24
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 2
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 23
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 1
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 22
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: TEMPLATE 0x94e70f0 QUERIES-- 0
> Apr  9 05:05:18 rockingham slapd[6662]: Unlock CR index = 0x94e70f0
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, SIZE=0
> Apr  9 05:05:18 rockingham slapd[6662]: STORED QUERIES = 21
> Apr  9 05:05:18 rockingham slapd[6662]: STALE QUERY REMOVED, CACHE =17
> entries
> Apr  9 05:05:18 rockingham slapd[6662]: Lock CR index = 0x94e6eb0
>
>
> Here's the backtrace:
>
> Program terminated with signal 11, Segmentation fault.
> #0  0x081764ed in pcache_query_cmp (v1=0xb1f0e900, v2=0x83e58955)
>       at pcache.c:694
> 694    return pcache_filter_cmp( q1->first, q2->first );
> (gdb) bt
> #0  0x081764ed in pcache_query_cmp (v1=0xb1f0e900, v2=0x83e58955)
>       at pcache.c:694
> #1  0x08199b6d in tavl_delete (root=0x825d7d0, data=0xb1f0e900,
>       fcmp=0x81764d8<pcache_query_cmp>) at tavl.c:202
> #2  0x08177ab4 in remove_from_template (qc=0xb1f0e900,
> template=0x94e6eb0)
>       at pcache.c:1302
> #3  0x0817b57d in consistency_check (ctx=0xb44201d0, arg=0x9537c50)
>       at pcache.c:2597
> #4  0x0819fd01 in ldap_int_thread_pool_wrapper (xpool=0x94a8fa0) at
> tpool.c:663
> #5  0x009c546b in start_thread () from /lib/libpthread.so.0
> #6  0x0091cdbe in clone () from /lib/libc.so.6
> (gdb)
> (gdb) p q1->first
> $3 = (Filter *) 0xb1f0d4c0
> (gdb) p q2->first
> Cannot access memory at address 0x83e58959
>
> Let me know what else would be useful from this backtrace.

Nothing obvious is jumping out here. Can you run a few of these slapds with 
libefence or valgrind?

-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/