Patch "arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one" has been added to the 3.18-stable tree

[<gregkh@linuxfoundation.org>]

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

    arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one

to the 3.18-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-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch
and it can be found in the queue-3.18 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 5553b142be11e794ebc0805950b2e8313f93d718 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Thu, 16 Nov 2017 17:58:21 +0000
Subject: arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one

From: Marc Zyngier <marc.zyngier@arm.com>

commit 5553b142be11e794ebc0805950b2e8313f93d718 upstream.

VTTBR_BADDR_MASK is used to sanity check the size and alignment of the
VTTBR address. It seems to currently be off by one, thereby only
allowing up to 39-bit addresses (instead of 40-bit) and also
insufficiently checking the alignment. This patch fixes it.

This patch is the 32bit pendent of Kristina's arm64 fix, and
she deserves the actual kudos for pinpointing that one.

Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation")
Reported-by: Kristina Martsenko <kristina.martsenko@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm/include/asm/kvm_arm.h |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -161,8 +161,7 @@
 #else
 #define VTTBR_X		(5 - KVM_T0SZ)
 #endif
-#define VTTBR_BADDR_SHIFT (VTTBR_X - 1)
-#define VTTBR_BADDR_MASK  (((1LLU << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT)
+#define VTTBR_BADDR_MASK  (((1LLU << (40 - VTTBR_X)) - 1) << VTTBR_X)
 #define VTTBR_VMID_SHIFT  (48LLU)
 #define VTTBR_VMID_MASK	  (0xffLLU << VTTBR_VMID_SHIFT)
 


Patches currently in stable-queue which might be from marc.zyngier@arm.com are

queue-3.18/arm-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch
queue-3.18/arm-kvm-survive-unknown-traps-from-guests.patch
queue-3.18/arm64-kvm-fix-vttbr_baddr_mask-bug_on-off-by-one.patch
queue-3.18/irqchip-crossbar-fix-incorrect-type-of-register-size.patch