[CRIU] [PATCH] mm: don't lose the SOFT_DIRTY flag on mprotect

[Andrew Morton]

On Thu, 30 Jan 2014 00:04:59 +0400 Andrey Vagin <avagin at openvz.org> wrote:

> The SOFT_DIRTY bit shows that the content of memory was changed
> after a defined point in the past. mprotect() doesn't change the
> content of memory, so it must not change the SOFT_DIRTY bit.
> 
> This patch does nothing with _PAGE_SWP_SOFT_DIRTY, becase pte_modify()
> is called only for present pages.

Standard complaint: when fixing a bug, please describe the end-user
visible effects of that bug.

afaict the effects are minor: snapshotting will save/copy more pages
than it needs to, but there will be no malfunction.  Hence a -stable
backport is unneeded.  Agree?