On Sat, Jun 26, 2010 at 4:22 AM, Dave Anderson <[email protected]> wrote:
> > ----- "marc pascual" <[email protected]> wrote: > > > Hello, > > > > I have this issue with compressed RHEL5 vmcore files, I can't get it > > to loaded to the crash utility. I don't have this problem with RHEL4 > vmcores (diskdump). > > The debuginfo kernel exactly matches the kernel version that generated > > the vmcore > > > > [r...@test-fc12 ~]# crash > usr/lib/debug/lib/modules/2.6.18-92.1.10.el5debug/vmlinux > /nas01/cores/2.6.18-92.1.10.el5.vmcore > > > > crash 4.0.9-2.fc12 > > Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 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 6.1 > > Copyright 2004 Free Software Foundation, Inc. > > GDB 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. > > Type "show copying" to see the conditions. > > There is absolutely no warranty for GDB. Type "show warranty" for > details. > > This GDB was configured as "x86_64-unknown-linux-gnu"... > > > > crash: page excluded: kernel virtual address: ffffffff804f1260 type: > "possible" > > WARNING: cannot read cpu_possible_map > > crash: usr/lib/debug/lib/modules/2.6.18-92.1.10.el5debug/vmlinux and > > /nas01/cores/2.6.18-92.1.10.el5.vmcore do not match! > > > > Usage: > > crash [-h [opt]][-v][-s][-i file][-d num] [-S] [mapfile] [namelist] > > [dumpfile] > > > > Enter "crash -h" for details. > > > > [r...@test-fc12 ~]# strings > usr/lib/debug/lib/modules/2.6.18-92.1.10.el5debug/vmlinux | grep 2.6 | head > -2 > > Linux version 2.6.18-92.1.10.el5debug ( > [email protected] ) (gcc version 4.1.2 20071124 > (Red Hat 4.1.2-42)) #1 SMP Wed Jul 23 04:27:38 EDT 2008 > > > > running strings on the rhel5 vmcore file: > > > > [r...@test-fc12 cores]# strings 2.6.18-92.1.10.el5.vmcore | grep 2.6 | > > head -2 > > 2X6 > > 2T6( > > If the diskdump was compressed (and with "makedumpfile -c" it is), then > unfortunately > looking for the "Linux version" string won't help. The utsname data may be > in the > compressed kdump header in more recent versions, so if you entered this: > > # crash -d1 vmlinux vmcore > ... > > then the dumpfile header will be immediately dumped, and the utsname has > most of > the relevant data from the "Linux version" string: > > diskdump_data: > filename: (null) > flags: 6 (KDUMP_CMPRS_LOCAL|ERROR_EXCLUDED) > dfd: 3 > ofp: 0 > machine_type: 62 (EM_X86_64) > > header: 19c42fe0 > signature: "KDUMP " > header_version: 1 > utsname: > sysname: Linux > nodename: hp-dl585g2-01.rhts.bos.redhat.com > release: 2.6.18-164.el5 > version: #1 SMP Tue Aug 18 15:51:48 EDT 2009 > machine: x86_64 > domainname: (none) > > But this was fixed fairly recently in makedumpfile, your dump may show > a bunch of (null) strings for the utsname data. > > One thing I notice is that the vmlinux file is "2.6.18-92.1.10.el5debug", > and although you haven't shown exactly what kernel the crashed kernel > was running, you've named it "2.6.18-92.1.10.el5.vmcore". If the crashed > kernel was running 2.6.18-92.1.10.el5, then you're using the wrong vmlinux > file, and you should be using: > > /usr/lib/debug/lib/modules/2.6.18-92.1.10.el5/vmlinux > > They 2.6.18-92.1.10.el5 and 2.6.18-92.1.10.el5debug kernels are completely > different kernels. > > If we presume that the crashed kernel and the vmlinux are *both* the > "debug" > variety, then if you extend the debug data output by entering -d4, you'll > see > every read attempt made from the dumpfile: > > # crash -d4 vmlinux vmcore > ... [ snip ] ... > 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 "x86_64-unknown-linux-gnu"... > > <readmem: ffffffff80447280, KVADDR, "possible", 32, (ROE), c8fce0> > cpu_possible_map: 0 1 2 3 4 5 6 7 > <readmem: ffffffff803ed5a0, KVADDR, "present", 32, (ROE), c8fce0> > cpu_present_map: 0 1 2 3 4 5 6 7 > <readmem: ffffffff803e8260, KVADDR, "online", 32, (ROE), c8fce0> > cpu_online_map: 0 1 2 3 4 5 6 7 > <readmem: ffffffff803ef200, KVADDR, "xtime", 16, (FOE), b50130> > <readmem: ffffffff80301320, KVADDR, "system_utsname", 390, (ROE), b5071c> > ... > > So, you can see that the very first readmem() is the cpu_possible_map > bitmap. > And in your case: > > > crash: page excluded: kernel virtual address: ffffffff804f1260 type: > "possible" > > WARNING: cannot read cpu_possible_map > > That first readmem() attempt failed because the page was explicitly > excluded by makedumpfile. But if makedumpfile's page exclusion mechanism > excluded the page containing that kernel data, I'd be very surprised. > > Dave > > > > does makedumpconfig's compression have something to do with this? from > > kdump.conf on the machine where i got that vmcore: > > ... > > core_collector makedumpfile -c -d31 > > ... > > > > Thank you in advace! > > > > Regards, > > Marc > > > > -- > Crash-utility mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/crash-utility > Dave, Thank you for your reply. However I'm slightly confused. the kernel version where I got the vmcore file is 2.6.18-92.1.10.el5 (x86_64). From my previous understanding, I should download and install kernel-debug-debuginfo-2.6.18-92.1.10.el5.x86_64.rpm. This package gives me 2.6.18-92.1.10.el5debug. However you mentioned that: "They 2.6.18-92.1.10.el5 and 2.6.18-92.1.10.el5debug kernels are completely different kernels." If this is the case, which package can I get 2.6.18-92.1.10.el5/vmlinux from? Assuming this is not the same kernel under /boot Thanks, Marc
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