Patch "KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interrupt" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interrupt

to the 4.9-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:
     kvm-arm-arm64-vgic-v2-do-not-use-active-pending-state-for-a-hw-interrupt.patch
and it can be found in the queue-4.9 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 ddf42d068f8802de122bb7efdfcb3179336053f1 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Tue, 2 May 2017 14:30:39 +0100
Subject: KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interrupt

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

commit ddf42d068f8802de122bb7efdfcb3179336053f1 upstream.

When an interrupt is injected with the HW bit set (indicating that
deactivation should be propagated to the physical distributor),
special care must be taken so that we never mark the corresponding
LR with the Active+Pending state (as the pending state is kept in
the physycal distributor).

Fixes: 140b086dd197 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 virt/kvm/arm/vgic/vgic-v2.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -168,6 +168,13 @@ void vgic_v2_populate_lr(struct kvm_vcpu
 	if (irq->hw) {
 		val |= GICH_LR_HW;
 		val |= irq->hwintid << GICH_LR_PHYSID_CPUID_SHIFT;
+		/*
+		 * Never set pending+active on a HW interrupt, as the
+		 * pending state is kept at the physical distributor
+		 * level.
+		 */
+		if (irq->active && irq_is_pending(irq))
+			val &= ~GICH_LR_PENDING_BIT;
 	} else {
 		if (irq->config == VGIC_CONFIG_LEVEL)
 			val |= GICH_LR_EOI;


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

queue-4.9/arm64-kvm-do-not-use-stack-protector-to-compile-el2-code.patch
queue-4.9/arm-kvm-do-not-use-stack-protector-to-compile-hyp-code.patch
queue-4.9/kvm-arm-arm64-vgic-v3-do-not-use-active-pending-state-for-a-hw-interrupt.patch
queue-4.9/kvm-arm-arm64-vgic-v2-do-not-use-active-pending-state-for-a-hw-interrupt.patch