kernel oops 817 Unable to handle kernel NULL pointer dereference at virtual address 00000000

[rgrish]

Hi Team,

Would like to know if the crash utility can be used to understand and debug kernel crashes and panics. I am facing one issue with armv GNU Linux and seeing kernel crash with sysrq trigger(-c) but not sure what is causing it. I can not configure kdump or vmcore and depenent on RAMOOPS file which gets generated with this crash to debug further. The kernel version for this armvl GNU Linux machine is 3.10.84.

I tried to install the crash utility in RHEL 5 and RHEL 6 but in both system I am facing different issues. Both are not LIVE system.

RHEL 5 -

checking dependency style of gcc... (cached) gcc3 checking whether g++ supports C++11 features by default... no checking whether g++ supports C++11 features with -std=gnu++11... no checking whether g++ supports C++11 features with -std=gnu++0x... no checking whether g++ supports C++11 features with -std=c++11... no checking whether g++ supports C++11 features with +std=c++11... no checking whether g++ supports C++11 features with -h std=c++11... no checking whether g++ supports C++11 features with -std=c++0x... no checking whether g++ supports C++11 features with +std=c++0x... no checking whether g++ supports C++11 features with -h std=c++0x... no configure: error: *** A compiler with support for C++11 language features is required. make[3]: *** [configure-gdbsupport] Error 1 make[2]: *** [all] Error 2

crash build failed

make[1]: *** [gdb_merge] Error 1 make: *** [all] Error 2

RHEL 6 -

/bin/sh ./../../move-if-change mmo.tmp mmo.texi touch mmo.stamp creating bfdver.texi restore=: && backupdir=".am$$" &&
rm -rf $backupdir && mkdir $backupdir &&
if (/home/roshang/crash-8.0.0/gdb-10.2/missing makeinfo --split-size=5000000 --split-size=5000000 --version) >/dev/null 2>&1; then
for f in bfd.info bfd.info-[0-9] bfd.info-[0-9][0-9] bfd.i[0-9] bfd.i[0-9][0-9]; do
if test -f $f; then mv $f $backupdir; restore=mv; else :; fi;
done;
else :; fi &&
if /home/roshang/crash-8.0.0/gdb-10.2/missing makeinfo --split-size=5000000 --split-size=5000000 -I .
-o bfd.info test -f 'bfd.texi' || echo './'bfd.texi;
then
rc=0;
else
rc=$?;
$restore $backupdir/* echo "./bfd.info" | sed 's|[^/]*$||';
fi;
rm -rf $backupdir; exit $rc /home/roshang/crash-8.0.0/gdb-10.2/missing: line 81: makeinfo: command not found WARNING: 'makeinfo' is missing on your system. You should only need it if you modified a '.texi' file, or any other file indirectly affecting the aspect of the manual. You might want to install the Texinfo package: http://www.gnu.org/software/texinfo/ The spurious makeinfo call might also be the consequence of using a buggy 'make' (AIX, DU, IRIX), in which case you might want to install GNU make: http://www.gnu.org/software/make/ make[5]: *** [bfd.info] Error 127 make[4]: *** [info-recursive] Error 1 make[3]: *** [all-bfd] Error 2 make[2]: *** [all] Error 2

crash build failed

make[1]: *** [gdb_merge] Error 1 make: *** [all] Error 2

Can someone provide any pointer how can I proceed here ? Also whether this crash utility can be used for debugging the OOPS file ?

[k-hagio]

Would like to know if the crash utility can be used to understand and debug kernel crashes and panics. I am facing one issue with armv GNU Linux and seeing kernel crash with sysrq trigger(-c) but not sure what is causing it. I can not configure kdump or vmcore and depenent on RAMOOPS file which gets generated with this crash to debug further. The kernel version for this armvl GNU Linux machine is 3.10.84.

Can someone provide any pointer how can I proceed here ? Also whether this crash utility can be used for debugging the OOPS file ?

The crash-utility is a tool to analyze vmcore and dumpfiles, you need to get it to use crash for such issues. I'm not sure what we can get with RAMOOPS, but I think at least crash cannot be used directly for it.

so fwiw, probably building crash-8 will need GCC 4.8.1 or later, according to [1]. [1] https://gcc.gnu.org/projects/cxx-status.html#cxx11