lkml.org 
[lkml]   [2009]   [Jan]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch] x86: fix PTE corruption issue while mapping RAM using /dev/mem

* Suresh Siddha <suresh.b.siddha@intel.com> wrote:

> From: Suresh Siddha <suresh.b.siddha@intel.com>
> Subject: x86: fix PTE corruption issue while mapping RAM using /dev/mem
>
> Beschorner Daniel reported:
> > hwinfo problem since 2.6.28, showing this in the oops:
> > Corrupted page table at address 7fd04de3ec00
>
> PaX Team reported a regression with this commit:
>
> > commit 9542ada803198e6eba29d3289abb39ea82047b92
> > Author: Suresh Siddha <suresh.b.siddha@intel.com>
> > Date: Wed Sep 24 08:53:33 2008 -0700
> >
> > x86: track memtype for RAM in page struct
>
> This commit breaks mapping any RAM page through /dev/mem, as the
> reserve_memtype() was not initializing the return attribute type and as such
> corrupting the PTE entry that was setup with the return attribute type.
>
> Because of this bug, application mapping this RAM page through /dev/mem
> will die with "Corrupted page table at address xxxx" message in the kernel
> log and also the kernel identity mapping which maps the underlying RAM
> page gets converted to UC.
>
> Fix this by initializing the return attribute type before calling
> reserve_ram_pages_type()
>
> Reported-by: PaX Team <pageexec@freemail.hu>
> Reported-and-tested-by: Beschorner Daniel <Daniel.Beschorner@facton.com>
> Tested-and-Acked-by: PaX Team <pageexec@freemail.hu>
> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
> Cc: <stable@kernel.org>
> ---

applied to tip/x86/urgent, thanks Suresh!

note that the patch caused some conflicts (there were other changes in
pat.c) - i merged it up manually but could you please check the final
commit in tip/master whether it's all OK?

Ingo


\
 
 \ /
  Last update: 2009-01-13 00:55    [W:0.047 / U:0.628 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site