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    SubjectRe: Linux 2.6.35.2
    From
    On Sat, Aug 14, 2010 at 8:47 PM, Linus Torvalds
    <torvalds@linux-foundation.org> wrote:
    > On Sat, Aug 14, 2010 at 11:27 AM, Ed Tomlinson <edt@aei.ca> wrote:
    >>
    >> It seems to be helping here.  Without it 35.2 would either stall in boot or give lots of tracebacks.  With it things
    >> start normally and my background stuff works as expected.
    >
    > Ok, thanks. I've committed it to the -git tree.
    >
    > Just to verify: you have CONFIG_HIGHPTE enabled on a x86-32 kernel,
    > right? I'd have expected this to not ever show up anywhere else, and
    > I'm just verifying that there isn't anything else going on. I'm
    > appending the commit message, the patch hasn't changed.
    >
    >                            Linus
    > ---
    >
    > Author: Linus Torvalds <torvalds@linux-foundation.org>
    > Date:   Sat Aug 14 11:44:56 2010 -0700
    >
    >    mm: fix page table unmap for stack guard page properly
    >
    >    We do in fact need to unmap the page table _before_ doing the whole
    >    stack guard page logic, because if it is needed (mainly 32-bit x86 with
    >    PAE and CONFIG_HIGHPTE, but other architectures may use it too) then it
    >    will do a kmap_atomic/kunmap_atomic.
    >
    >    And those kmaps will create an atomic region that we cannot do
    >    allocations in.  However, the whole stack expand code will need to do
    >    anon_vma_prepare() and vma_lock_anon_vma() and they cannot do that in an
    >    atomic region.
    >
    >    Now, a better model might actually be to do the anon_vma_prepare() when
    >    _creating_ a VM_GROWSDOWN segment, and not have to worry about any of
    >    this at page fault time.  But in the meantime, this is the
    >    straightforward fix for the issue.
    >
    >    See https://bugzilla.kernel.org/show_bug.cgi?id=16588 for details.
    >
    >    Reported-by: Wylda <wylda@volny.cz>
    >    Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
    >    Reported-by: Mike Pagano <mpagano@gentoo.org>
    >    Reported-by: François Valenduc <francois.valenduc@tvcablenet.be>
    >    Tested-by: Ed Tomlinson <edt@aei.ca>
    >    Cc: Pekka Enberg <penberg@kernel.org>
    >    Cc: Greg KH <gregkh@suse.de>
    >    Cc: stable@kernel.org
    >    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    >
    >  mm/memory.c |   13 ++++++-------
    >  1 files changed, 6 insertions(+), 7 deletions(-)
    >

    Missing: Tested-by: Wylda <wylda@volny.cz>

    I am building now upstream (2.6.35-git15) with that patch to see if it
    fixes the issues there, too. Report later.

    - Sedat -
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