Re: [v4 3/6] mm: uninitialized struct page poisoning sanity checking

[Ingo Molnar]

* Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> wrote:

> During boot we poison struct page memory in order to ensure that no one is
> accessing this memory until the struct pages are initialized in
> __init_single_page().
> 
> This patch adds more scrutiny to this checking by making sure that flags
> do not equal the poison pattern when they are accessed.  The pattern is all
> ones.
> 
> Since node id is also stored in struct page, and may be accessed quite
> early, we add this enforcement into page_to_nid() function as well.
> Note, this is applicable only when NODE_NOT_IN_PAGE_FLAGS=n
> 
> Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
> Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>

Please always start patch titles with a verb, i.e.:

 mm: Add uninitialized struct page poisoning sanity check

or so.

Thanks,

	Ingo