Re: [PATCHv2 2/2] mm/page_poisoning.c: Allow for zero poisoning

From: Rafael J. Wysocki
Date: Thu Jan 28 2016 - 22:54:53 EST


On Thursday, January 28, 2016 06:38:19 PM Laura Abbott wrote:
> By default, page poisoning uses a poison value (0xaa) on free. If this
> is changed to 0, the page is not only sanitized but zeroing on alloc
> with __GFP_ZERO can be skipped as well. The tradeoff is that detecting
> corruption from the poisoning is harder to detect. This feature also
> cannot be used with hibernation since pages are not guaranteed to be
> zeroed after hibernation.
>
> Credit to Grsecurity/PaX team for inspiring this work
>
> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxxxxxxxxx>

The hibernation disabling part is fine by me.

Please feel free to add an ACK from me to this if that helps.

Thanks,
Rafael