On Fri 2016-09-09 10:43:32, Anisse Astier wrote:
> PAGE_POISONING_ZERO disables zeroing new pages on alloc, they are
> poisoned (zeroed) as they become available.
> In the hibernate use case, free pages will appear in the system without
> being cleared, left there by the loading kernel.
>
> This patch will make sure free pages are cleared on resume when
> PAGE_POISONING_ZERO is enabled. We free the pages just after resume
> because we can't do it later: going through any device resume code might
> allocate some memory and invalidate the free pages bitmap.
>
> Thus we don't need to disable hibernation when PAGE_POISONING_ZERO is
> enabled.
>
> Signed-off-by: Anisse Astier <ani...@astier.eu>
> Cc: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
> Cc: Laura Abbott <labb...@fedoraproject.org>
> Cc: Mel Gorman <mgor...@suse.de>
> Cc: Rafael J. Wysocki <r...@rjwysocki.net>
Looks reasonable to me.
Acked-by: Pavel Machek <pa...@ucw.cz>
Actually.... this takes basically zero time come. Do we want to do it
unconditionally?
(Yes, it is free memory, but for sake of debugging, I guess zeros are
preffered to random content that changed during hibernation.)
(But that does not change the Ack.)
Best regards,
Pavel
--
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