Re: [RFC Patch 0/2] Slimdump framework using CRASH_REASON - v2

[Vivek Goyal <vgoyal@redhat.com>]

On Mon, Nov 21, 2011 at 03:24:05PM +0530, K.Prasad wrote:
> Hi All,
> 	In furtherance of the previous discussion regarding 'slimdump'
> (refer: http://article.gmane.org/gmane.linux.kernel/1204967), it was
> decided that,
> 
> - An entry in VMCOREINFO elf-note be added to denote the cause of crash,
>   instead of creating a new elf-note.
> 
> - Upstream tools such as 'makedumpfile' and 'crash' be modified to
>   recognise this string and inform the user accordingly.
> 
> Accordingly, this new version of the patchset makes the following
> changes 
> 
> Changelog - version 2
> -----------------------
> (First version posted here:
> http://article.gmane.org/gmane.linux.kernel/1198435)
> 
> - Append VMCOREINFO elf-note with a new variable CRASH_REASON whose
>   value will be populated using arch_add_crash_reason() function.
> 
> - Define arch_add_crash_reason() in the x86 MCE path to return "PANIC_MCE"
>   in the panic path of MCE.
> 
> - 'makedumpfile' tool is taught to recognise PANIC_MCE string as one
>   value of CRASH_REASON for which 'slimdump' must be captured.

So again, what is slimdump? I mean, what information is now being captured
in the case of slimdump? Are you capturing atleast the kernel message
buffers? I am assuming that any register info emitted on console will
make into kernel buffers and that should be useful to figure out what
MCE happened.

Thanks
Vivek