lkml.org 
[lkml]   [2015]   [Apr]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] mm/hugetlb: use pmd_page() in follow_huge_pmd()
On Fri, 10 Apr 2015 10:08:49 +0200 Gerald Schaefer <gerald.schaefer@de.ibm.com> wrote:

> On Thu, 9 Apr 2015 12:41:47 -0700 (PDT)
> David Rientjes <rientjes@google.com> wrote:
>
> > On Thu, 9 Apr 2015, Gerald Schaefer wrote:
> >
> > > commit 61f77eda "mm/hugetlb: reduce arch dependent code around
> > > follow_huge_*" broke follow_huge_pmd() on s390, where pmd and pte
> > > layout differ and using pte_page() on a huge pmd will return wrong
> > > results. Using pmd_page() instead fixes this.
> > >
> > > All architectures that were touched by commit 61f77eda have
> > > pmd_page() defined, so this should not break anything on other
> > > architectures.
> > >
> > > Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
> > > Cc: stable@vger.kernel.org # v3.12
> >
> > Acked-by: David Rientjes <rientjes@google.com>
> >
> > I'm not sure where the stable cc came from, though: commit 61f77eda
> > makes s390 use a generic version of follow_huge_pmd() and that
> > generic version is buggy for s930 because of commit e66f17ff7177
> > ("mm/hugetlb: take page table lock in follow_huge_pmd()"). Both of
> > those are 4.0 material, though, so why is this needed for stable 3.12?
>
> Both commits 61f77eda and e66f17ff already made it into the 3.12 stable
> tree, probably because of SLES 12 (actually that's how I noticed them).
>
> But I guess I screwed up the stable CC, stable@vger.kernel.org.#.v3.12
> somehow doesn't look right, not sure if the CC in the patch header
> suffices. Looks like Jiri Slaby added the patches to 3.12, putting him
> on CC now.

hm. I think I'll make it

Fixes: 61f77eda "mm/hugetlb: reduce arch dependent code around follow_huge_*"
...
Cc: <stable@vger.kernel.org>

There's enough info here for the various tree maintainers to work out
whether their kernel needs this fix.



\
 
 \ /
  Last update: 2015-04-10 23:01    [W:0.276 / U:0.092 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site