Patch "arm64: fix midr range for Cortex-A57 erratum 832075" has been added to the 3.19-stable tree

Patch "arm64: fix midr range for Cortex-A57 erratum 832075" has been added to the 3.19-stable tree

[gregkh]

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

    arm64: fix midr range for Cortex-A57 erratum 832075

to the 3.19-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:
     arm64-fix-midr-range-for-cortex-a57-erratum-832075.patch
and it can be found in the queue-3.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 6d1966dfd6e0ad2f8aa4b664ae1a62e33abe1998 Mon Sep 17 00:00:00 2001
From: Bo Yan <byan@nvidia.com>
Date: Tue, 31 Mar 2015 21:30:48 +0100
Subject: arm64: fix midr range for Cortex-A57 erratum 832075

From: Bo Yan <byan@nvidia.com>

commit 6d1966dfd6e0ad2f8aa4b664ae1a62e33abe1998 upstream.

Register MIDR_EL1 is masked to get variant and revision fields, then
compared against midr_range_min and midr_range_max when checking
whether CPU is affected by any particular erratum. However, variant
and revision fields in MIDR_EL1 are separated by 16 bits, so the min
and max of midr range should be constructed accordingly, otherwise
the patch will not be applied when variant field is non-0.

Acked-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Bo Yan <byan@nvidia.com>
[will: use MIDR_VARIANT_SHIFT to construct upper bound]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm64/kernel/cpu_errata.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -88,7 +88,8 @@ struct arm64_cpu_capabilities arm64_erra
 	/* Cortex-A57 r0p0 - r1p2 */
 		.desc = "ARM erratum 832075",
 		.capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
-		MIDR_RANGE(MIDR_CORTEX_A57, 0x00, 0x12),
+		MIDR_RANGE(MIDR_CORTEX_A57, 0x00,
+			   (1 << MIDR_VARIANT_SHIFT) | 2),
 	},
 #endif
 	{


Patches currently in stable-queue which might be from byan@nvidia.com are

queue-3.19/arm64-fix-midr-range-for-cortex-a57-erratum-832075.patch