How to store kernel pranic/oops

How to store kernel pranic/oops

[Marco Stornelli]

Hi,

I know the open project proposal 2010 is closed, but it's just to start
a discussion. It would be nice to save oops/panic automatically in a
structure/file in ram. At the moment there are two way to save
information: mtdoops (save the information in flash), with kdump/kexec
(we can extract the dmesg from vmcore file). With these tools there are
some drawbacks:

1) There are embedded systems without a flash where to save the information;
2) we could consider this kind of logs too volatile for a flash, I mean
there's no reason to store it for a long time, it's important to recover
and read them as soon as possible, at next boot for example.
3) kdump requires a lot of ram and resources for embedded systems.
4) kexec is available only for some archs.

It would be nice to have a "ramoops" to save in a circular buffer in a
persistent ram this kind of information. Any comments? Is there already
anything similar out-of-tree?

Marco

Re: How to store kernel pranic/oops

[David Woodhouse]

On Mon, 2009-12-28 at 12:43 +0100, Marco Stornelli wrote:
> It would be nice to have a "ramoops" to save in a circular buffer in a
> persistent ram this kind of information. Any comments? Is there already
> anything similar out-of-tree? 

Can't it be done with what's in the tree already? Just create an MTD
device using phram or something else, then point mtdoops at it.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse@intel.com                              Intel Corporation