Red Hat Bugzilla – Bug 450155
/sbin/dump causes a kernel panic in map_bio() /
Last modified: 2014-06-18 04:01:45 EDT
Description of problem:
this applies to kernels 2.6.19-92.el5 and 2.6.18-53
assign to kernel MD component.
I installed a linux server and run a backup using dump.
The effect was the the kernel panic'ed in map_bio() with 2.6.18-53.1.4.el5.
After I upgraded to 2.6.18-92 the system seem to hang.
Always after some time, ie. when 17% of the dump is done, sometime earlier.
I do a dump level 0 (-b64) from a RAID 1 array mounted on /data to a
file in root fs in /backup. It's called /dev/mapper/nvidia_bcacfdbgp1
The system is in normal user mode, but also in single user mode.
Steps to reproduce:
/sbin/dump -0u -b64 -f /backup/data.0 /data
either in single or multiuser mode.
Maybe it has something todo with the -b option? I've created a few backups
before I introduced the -b64 option to improve the speed.
-b64 seems to panic always. Right now I start over to test with -b16, but this
EIP was pointing to map_bio().
Callstack which I could read of the console:
Please, try to reproduce this problem and attach the whole debug message, you've
got. That will provide us detailed information to work.
I had reconfigured the machine in order to get it stable running, so I cannot
reproduce it anymore. The output on the console is the same as I wrote.
It a HP Proliant ML115. I've had / on a 160GB disk and two 500GB discs for the
RAID array mounted on /data. All fileststems with ext3.
So dump was reading from /data and storing data on /backup.
The size of used space in /data about 40GB. / had enough space to store the
backup. I played with the blocksizes, but got also problems at 32. 16 or lower
takes too much time to do the backup.
Hope you can reproduce it.
It would be _very_ helpful to have mentioned backtrace with the
I'm trying to reproduce it but have no luck so far ...
Tried to reproduce it in many ways, even on the same configuration: raid1(using
dm),... played with blocksize variable. Every backup were successful.
No similar complaints were found in lkml and internet. I need detailed backtrace
for further investigation.
So that putting bug into NEEDINFO state.