Description of problem: I compile crash-5.0.1-0.src.rpm and find that "kmem -s list" sub-command in crash utility can't read kmem_cache_s.name string. Version-Release number of selected component (if applicable): crash-5.0.1-0.src.rpm How reproducible: 100% reproducible Steps to Reproduce: 1. ./crash 2. kmem -s list Actual results: Kmem cannot read kmem_cache_s.name string at 1 Expected results: Slab cache name and address should be listed. Additional info: [root@lhc crash-5.0.1]# ./crash crash 5.0.1 Copyright (C) 2002-2010 Red Hat, Inc. Copyright (C) 2004, 2005, 2006 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.0 Copyright (C) 2009 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i686-pc-linux-gnu"... KERNEL: /usr/lib/debug/lib/modules/2.6.18-8.el5/vmlinux DUMPFILE: /dev/crash CPUS: 1 DATE: Thu Apr 8 23:14:25 2010 UPTIME: 04:36:14 LOAD AVERAGE: 1.16, 0.63, 0.47 TASKS: 145 NODENAME: lhc RELEASE: 2.6.18-8.el5 VERSION: #1 SMP Fri Jan 26 14:15:21 EST 2007 MACHINE: i686 (1995 Mhz) MEMORY: 512 MB PID: 10440 COMMAND: "crash" TASK: dc0b6000 [THREAD_INFO: cafcf000] CPU: 0 STATE: TASK_RUNNING (ACTIVE) crash> kmem -s list c066c520 kmem_cache kmem: WARNING: cannot read kmem_cache_s.name string at 1 c0793ed8 (unknown) d9cd8c80 VMBlockInodeCache d9cd8d80 blockInfoCache d9cd8e80 hgfsInodeCache ddcb56c0 hgfsReqCache ddcb55c0 rpc_buffers ddcb54c0 rpc_tasks ddcb53c0 rpc_inode_cache ddcb57c0 ip_conntrack_expect ddcb58c0 ip_conntrack ddcb59c0 iser_descriptors ddcb52c0 ib_mad ddcb51c0 jbd_1k ddcb50c0 dm_mpath ddcb5ac0 fib6_nodes ddcb5bc0 ip6_dst_cache ddcb5cc0 ndisc_cache ddcb5dc0 RAWv6 ddcb5ec0 UDPv6 dfb37480 tw_sock_TCPv6 dfb37380 request_sock_TCPv6 crash> q [root@lhc crash-5.0.1]#
Fixed upstream in version 5.0.2: http://people.redhat.com/anderson/crash.changelog.html - Fix for the "kmem -s list" command option on non-CONFIG_SLUB kernels that contain a "cache_chain" list_head symbol instead of having a "#define cache_chain (cache_cache.next)" construct. Without the patch, the command would incorrectly presume that the "cache_chain" address was that of a kmem_cache structure, may display a warning message "kmem: WARNING: cannot read kmem_cache_s.name string at <address>", and then show the "cache_chain" symbol address followed either by a name of "(unknown)" or by a string of gibberish. (anderson) But it's not a really a problem -- it's trying to read a slab cache name string from the "cache_chain" list_head, which is not a kmem_cache structure. But the remainder of the list of cache slab names are correct, so it's a harmless warning.
Cool! Thanks.
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: When running the "kmem -s list" command, the crash utility was unable to read the "kmem_cache_s.name" string. To resolve this issue, the utility has been adjusted to skip the "list_head", and the above command now displays the actual "kmem_cache" names or addresses only.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-0059.html