This is a note to let you know that I've just added the patch titled

    ARM: 6489/1: thumb2: fix incorrect optimisation in usracc

to the 2.6.32-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-6489-1-thumb2-fix-incorrect-optimisation-in-usracc.patch
and it can be found in the queue-2.6.32 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 1142b71d85894dcff1466dd6c871ea3c89e0352c Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Fri, 19 Nov 2010 13:18:31 +0100
Subject: ARM: 6489/1: thumb2: fix incorrect optimisation in usracc

From: Will Deacon <[email protected]>

commit 1142b71d85894dcff1466dd6c871ea3c89e0352c upstream.

Commit 8b592783 added a Thumb-2 variant of usracc which, when it is
called with \rept=2, calls usraccoff once with an offset of 0 and
secondly with a hard-coded offset of 4 in order to avoid incrementing
the pointer again. If \inc != 4 then we will store the data to the wrong
offset from \ptr. Luckily, the only caller that passes \rept=2 to this
function is __clear_user so we haven't been actively corrupting user data.

This patch fixes usracc to pass \inc instead of #4 to usraccoff
when it is called a second time.

Reported-by: Tony Thompson <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Russell King <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/arm/include/asm/assembler.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -215,7 +215,7 @@
        @ Slightly optimised to avoid incrementing the pointer twice
        usraccoff \instr, \reg, \ptr, \inc, 0, \cond, \abort
        .if     \rept == 2
-       usraccoff \instr, \reg, \ptr, \inc, 4, \cond, \abort
+       usraccoff \instr, \reg, \ptr, \inc, \inc, \cond, \abort
        .endif
 
        add\cond \ptr, #\rept * \inc


Patches currently in stable-queue which might be from [email protected] are

queue-2.6.32/arm-6489-1-thumb2-fix-incorrect-optimisation-in-usracc.patch

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