Development/Howto/Report Kernel Bugs
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Reporting Kernel bugs
This document describes how to provide useful information in kernel bug reports.
Contents |
Introduction
The form below is the suggested way to make kernel bugs reports on bugzilla, or even by e-mail. Note that you aren't obliged to use the bug reporting format, it is provided as a guide to the kind of information that can be useful to developers.
Kernel bug report format
- One line summary of the problem (on bugzilla, this is the 'summary' field):
- Full description of the problem/report:
- Keywords (i.e., modules, networking, kernel):
- Mandriva kernel version (from /proc/version ):
- Most recent Mandriva kernel version which did not have the bug:
- Output of Oops.. message (if applicable)
- Steps to reproduce (you can append shell scripts or little programs which triggers the bug)
- Environment
- Mandriva distribution version (from /etc/mandriva-release)
- Processor information (from /proc/cpuinfo ):
- /etc/modprobe.conf
- Module information ( lsmod ):
- Loaded driver and hardware information ( /proc/ioports, /proc/iomem )
- PCI information ( lspci -vvv as root)
- SCSI information (from /proc/scsi/scsi )
- Other information that might be relevant to the problem (please look in /proc, /sys and include all information that you think to be relevant):
- Other notes, patches, fixes, workarounds:
In case of a boot time panic
A boot time panic is an error at boot that ends with messages similar to:
mounting root filesystem /dev/root with flags noatime mount:error 19 mounting ext3 flags noatime switching to new root error opening /dev/console!!!:2 umounting old /proc umounting old /sys switchroot mount failed:22 initrd failed kernel panic - not syning
In this case we will need:
- Screen capture until the panic (use a camera, a SerialConsole, or a pencil).
Be sure to include anything from line Red Hat nash version 4.2.17mdk starting
up to the line Kernel Panic - notsyncing : Attempted to kill init!
Unfortunately since the machine panicked in graphic mode you will probably not be able to scroll up using Shift-PgUp
so you will have to edit the bootloader command line and add the words vga=ask,
then choose a suitable text mode (the one with the more lines available)
- stdout and stderr from mkinitrd invocation, use the following command:
sh -x /sbin/mkinitrd -v -f /boot/initrd-X.Y.Z-Wmdv.img X.Y.Z-Wmdv > /tmp/mkinitrd.log 2>/tmp/mkinitrd.err where X.Y.Z-Wmdv is the version of the kernel you are installing. To do the above you will need to boot from an older kernel, if you have a working one, or from the rescue CD.
References
- This document is based on http://www.kernel.org/pub/linux/docs/lkml/reporting-bugs.html
- SerialConsole
- Linux's sysrq: http://www.linux-m32r.org/lxr/http/source/Documentation/sysrq.txt

