4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andre Przywara <[email protected]>

[ Upstream commit 62b06f8f429cd233e4e2e7bbd21081ad60c9018f ]

Our irq_is_pending() helper function accesses multiple members of the
vgic_irq struct, so we need to hold the lock when calling it.
Add that requirement as a comment to the definition and take the lock
around the call in vgic_mmio_read_pending(), where we were missing it
before.

Fixes: 96b298000db4 ("KVM: arm/arm64: vgic-new: Add PENDING registers handlers")
Signed-off-by: Andre Przywara <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 virt/kvm/arm/vgic/vgic-mmio.c |    3 +++
 virt/kvm/arm/vgic/vgic.h      |    1 +
 2 files changed, 4 insertions(+)

--- a/virt/kvm/arm/vgic/vgic-mmio.c
+++ b/virt/kvm/arm/vgic/vgic-mmio.c
@@ -110,9 +110,12 @@ unsigned long vgic_mmio_read_pending(str
        /* Loop over all IRQs affected by this read */
        for (i = 0; i < len * 8; i++) {
                struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+               unsigned long flags;
 
+               spin_lock_irqsave(&irq->irq_lock, flags);
                if (irq_is_pending(irq))
                        value |= (1U << i);
+               spin_unlock_irqrestore(&irq->irq_lock, flags);
 
                vgic_put_irq(vcpu->kvm, irq);
        }
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -96,6 +96,7 @@
 /* we only support 64 kB translation table page size */
 #define KVM_ITS_L1E_ADDR_MASK          GENMASK_ULL(51, 16)
 
+/* Requires the irq_lock to be held by the caller. */
 static inline bool irq_is_pending(struct vgic_irq *irq)
 {
        if (irq->config == VGIC_CONFIG_EDGE)


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