[PATCH] kexec: crash: don't save swapper_pg_dir for !CONFIG_MMU configurations

[Will Deacon]

On Sat, Feb 25, 2012 at 02:37:49AM +0000, Simon Horman wrote:
> On Fri, Feb 24, 2012 at 02:40:47PM +0000, Will Deacon wrote:
> > nommu platforms don't have very interesting swapper_pg_dir pointers and
> > usually just #define them to NULL, meaning that we can't include them in
> > the vmcoreinfo on the kexec crash path.
> > 
> > This patch only saves the swapper_pg_dir if we have an MMU.
> 
> Hi Will,

Hi Simon,

> might this cover cases where swapper_pg_dir is interesting?

The only case where it's interesting is when you have CONFIG_MMU enabled -
otherwise it's always NULL. If it's #defined as NULL, the current code will
fail at build time so simply omitting it from the dump seems like the best
bet to me (the alternative being to add a NULL entry explicitly, but I don't
see what the gains us).

Cheers,

Will