[Crash-utility] [Patch 1/4][kernel][slimdump] Add new elf-note of type NT_NOCOREDUMP to capture slimdump

[K.Prasad]

On Tue, Oct 04, 2011 at 10:04:37AM -0400, Vivek Goyal wrote:
> On Mon, Oct 03, 2011 at 01:02:03PM +0530, K.Prasad wrote:
> > There are certain types of crashes induced by faulty hardware in which
> > capturing crashing kernel's memory (through kdump) makes no sense (or sometimes
> > dangerous).
> > 
> > A case in point, is unrecoverable memory errors (resulting in fatal machine
> > check exceptions) in which reading from the faulty memory location from the
> > kexec'ed kernel will cause double fault and system reset (leaving no
> > information for the user).
> 
> Prasad,
> 
> I am just trying to remember what was wrong with Andi's approach of
> disable MCE while copying the dump?
>

Hi Vivek,
	The behaviour upon a read operation on an UC memory location is
undefined and so we want to avoid it (previously discussed here:
http://article.gmane.org/gmane.linux.kernel/1146799). When we disable
MCE and copy the dump, we will invariably read the faulty memory
location.

Thanks,
K.Prasad