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

    ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling MMU

to the 3.4-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-7953-1-mm-ensure-tlb-invalidation-is-complete-before-enabling-mmu.patch
and it can be found in the queue-3.4 subdirectory.

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


>From bae0ca2bc550d1ec6a118fb8f2696f18c4da3d8e Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Fri, 7 Feb 2014 19:12:20 +0100
Subject: ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling 
MMU

From: Will Deacon <[email protected]>

commit bae0ca2bc550d1ec6a118fb8f2696f18c4da3d8e upstream.

During __v{6,7}_setup, we invalidate the TLBs since we are about to
enable the MMU on return to head.S. Unfortunately, without a subsequent
dsb instruction, the invalidation is not guaranteed to have completed by
the time we write to the sctlr, potentially exposing us to junk/stale
translations cached in the TLB.

This patch reworks the init functions so that the dsb used to ensure
completion of cache/predictor maintenance is also used to ensure
completion of the TLB invalidation.

Reported-by: Albin Tonnerre <[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/mm/proc-v6.S |    3 ++-
 arch/arm/mm/proc-v7.S |    2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -202,7 +202,6 @@ __v6_setup:
        mcr     p15, 0, r0, c7, c14, 0          @ clean+invalidate D cache
        mcr     p15, 0, r0, c7, c5, 0           @ invalidate I cache
        mcr     p15, 0, r0, c7, c15, 0          @ clean+invalidate cache
-       mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
 #ifdef CONFIG_MMU
        mcr     p15, 0, r0, c8, c7, 0           @ invalidate I + D TLBs
        mcr     p15, 0, r0, c2, c0, 2           @ TTB control register
@@ -212,6 +211,8 @@ __v6_setup:
        ALT_UP(orr      r8, r8, #TTB_FLAGS_UP)
        mcr     p15, 0, r8, c2, c0, 1           @ load TTB1
 #endif /* CONFIG_MMU */
+       mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer and
+                                               @ complete invalidations
        adr     r5, v6_crval
        ldmia   r5, {r5, r6}
 #ifdef CONFIG_CPU_ENDIAN_BE8
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -246,7 +246,6 @@ __v7_setup:
 
 3:     mov     r10, #0
        mcr     p15, 0, r10, c7, c5, 0          @ I+BTB cache invalidate
-       dsb
 #ifdef CONFIG_MMU
        mcr     p15, 0, r10, c8, c7, 0          @ invalidate I + D TLBs
        v7_ttb_setup r10, r4, r8, r5            @ TTBCR, TTBRx setup
@@ -255,6 +254,7 @@ __v7_setup:
        mcr     p15, 0, r5, c10, c2, 0          @ write PRRR
        mcr     p15, 0, r6, c10, c2, 1          @ write NMRR
 #endif
+       dsb                                     @ Complete invalidations
 #ifndef CONFIG_ARM_THUMBEE
        mrc     p15, 0, r0, c0, c1, 0           @ read ID_PFR0 for ThumbEE
        and     r0, r0, #(0xf << 12)            @ ThumbEE enabled field


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

queue-3.4/arm-7953-1-mm-ensure-tlb-invalidation-is-complete-before-enabling-mmu.patch
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