Re: [PATCH RESEND] mm: don't zero ballooned pages
From: David Hildenbrand
Date: Mon Aug 07 2017 - 05:37:37 EST
> Maybe it is my absolute lack of familiarity with what the host actually
> does with balloon pages but I fail to see why the above matters at all.
> ksm will not try to merge sub page units (4k for hugetlb or a large base
> page). And if you need to hide the guest contents then the host can
> clear the respective subpage just fine. So could you be more explicit
> why MADV_DONTNEED matters at all? Also does any host actually share sub
> pages between different guests? This sounds like a bad idea to me in
> general.
>
Okay, I think I got the issue wrong. I thought that the original patch
tried to also fix a corner case where the guest would assume that it
would get supplied zero pages afterwards. Please ignore the noise. :)
--
Thanks,
David