Re: [Crash-utility] crash bug on 2.6.27.8
----- "Jun Koi" <junkoi2004(a)gmail.com> wrote:
On Mon, Feb 9, 2009 at 11:51 PM, Dave Anderson
<anderson(a)redhat.com>
wrote:
>
> ----- "Jun Koi" <junkoi2004(a)gmail.com> wrote:
>
>> Hi,
>>
>> When using the latest crash on 2.6.27.14 to analyze live memory
>> (running crash without any option), I got a bug like below. How can
I
>> fix that?
>>
>> (A similar problem is also seen on 2.6.27.8)
>>
>> Thanks,
>> Jun
>
> The "read error" indications are most likely due to your kernel
> being configured with CONFIG_STRICT_DEVMEM, which restricts
> /dev/mem access to the first 256 pages of physical memory,
> which makes it useless for the crash utility.
Thanks a lot for the information - I can fix the kernel here.
But perhaps it is better to give some hints when we have such a error
report, so users know that they should turn off the above
configuration? I am sure that many people will have this problem, as
the option may be ON by default.
Thanks,
Jun
Good idea -- I'll put something in place for the next release.
I'll also look into creating a web page with a "canned answer"
for this issue, including directions for going the crash-module-build
or kprobe routes for those who cannot rebuild their kernels.
Thanks,
Dave