linux-kernel - Questions and problems regarding kdump

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Date:	Sat, 19 Apr 2014 00:24:01 +0200
From:	GEO <1g2e3o4@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: Questions and problems regarding kdump

Hi,

I have successfully set up kdump to handle oops/panics, however I have a few 
question regarding the whole process. 
First of all, I am currently under linux 3.13.0-24 and my /etc/default/kdump-
tools contains the following options:

USE_KDUMP=1
KDUMP_SYSCTL="kernel.panic_on_oops=1"
KDUMP_FAIL_CMD="reboot -f"
KDUMP_CMDLINE_APPEND="maxcpus=1"

The default for KDUMP_CMDLINE_APPEND= seems to be "irqpoll maxcpus=1 nousb", 
but I removed nousb as I have a system running where the root device is 
connect over a usb port. 
What are the risks of removing irqpoll?
I removed the option from the file because I seemingly got a kernel panic of 
the invoked crash kernel when it was called with irqpoll option. 
The output can be seen in the two attached images (I got to this screen after 
I invoked a panic with "echo c > /proc/sysrqhandler ", screen turned black for 
short time, which indicates the other kernel is starting and then received the 
output as seen). 

When the crash kernel is invoked it boots to the Desktop, which seems very 
unnecessary because it will reboot anyway after dumping the memory. What 
option would you recommend for the kernel to just dump the memory (network not 
needed)?

Thanks

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