Re: [PATCH RFC] mm: Rework virtual memory accounting

From: Andrew Morton
Date: Fri Jan 22 2016 - 15:21:13 EST

On Fri, 22 Jan 2016 20:42:11 +0100 Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote:

> On 12/28/2015 11:22 PM, Linus Torvalds wrote:
> > On Mon, Dec 28, 2015 at 1:10 PM, Cyrill Gorcunov <gorcunov@xxxxxxxxx> wrote:
> >> Really sorry for delays. Konstantin, I slightly updated the
> >> changelog (to point where problem came from). Linus are you
> >> fine with accounting not only anonymous memory in VmData?
> >
> > The patch looks ok to me. I guess if somebody relies on old behavior
> > we may have to tweak it a bit, but on the whole this looks sane and
> > I'd be happy to merge it in the 4.5 merge window (and maybe even have
> > it marked for stable if it works out)
> >
> Just want to mention that this patch breaks older versions of valgrind
> (including the current release)
> It is fixed in trunk (and even triggered some good cleanups, so the valgrind
> developers do NOT want it to get reverted). Rawhide already has the valgrind
> fix, others might not, so if we consider this for stable, things might break
> here and there, but in general this looks like a good cleanup.

OK, thanks - that sounds reasonable, although a bit worrisome - what
other userspace was affected? In some cases people won't find out for

84638335900f199 ("mm: rework virtual memory accounting") did not have
the cc:stable tag so it should avoid the -stable dragnet.