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

From: Pavel Machek
Date: Fri Jan 29 2016 - 05:46:02 EST


Hi!

> 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.

So... this makes kernel harder to debug for performance advantage...?
If so.. how big is the performance advantage?
Pavel
--
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