Messages in this thread Patch in this message | | | From | Luis Henriques <> | Subject | [PATCH 3.5 03/62] ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling MMU | Date | Wed, 5 Mar 2014 14:36:07 +0000 |
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3.5.7.32 -stable review patch. If anyone has any objections, please let me know.
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From: Will Deacon <will.deacon@arm.com>
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 <Albin.Tonnerre@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/arm/mm/proc-v6.S | 3 ++- arch/arm/mm/proc-v7.S | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S index 897486c..4d2e447 100644 --- 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 diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index c2e2b66..fb489cc 100644 --- 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 -- 1.9.0
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