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 <anisse@xxxxxxxxx> > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: Laura Abbott <labbott@xxxxxxxxxxxxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxx> > Cc: Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> Looks reasonable to me. Acked-by: Pavel Machek <pavel@xxxxxx> 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 -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>