From: Marc Zyngier maz@kernel.org
commit 82e40f558de566fdee214bec68096bbd5e64a6a4 upstream.
A guest is not allowed to inject a SGI (or clear its pending state) by writing to GICD_ISPENDR0 (resp. GICD_ICPENDR0), as these bits are defined as WI (as per ARM IHI 0048B 4.3.7 and 4.3.8).
Make sure we correctly emulate the architecture.
Fixes: 96b298000db4 ("KVM: arm/arm64: vgic-new: Add PENDING registers handlers") Cc: stable@vger.kernel.org # 4.7+ Reported-by: Andre Przywara andre.przywara@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- virt/kvm/arm/vgic/vgic-mmio.c | 18 ++++++++++++++++++ virt/kvm/arm/vgic/vgic-v2.c | 5 ++++- virt/kvm/arm/vgic/vgic-v3.c | 5 ++++- 3 files changed, 26 insertions(+), 2 deletions(-)
--- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -195,6 +195,12 @@ static void vgic_hw_irq_spending(struct vgic_irq_set_phys_active(irq, true); }
+static bool is_vgic_v2_sgi(struct kvm_vcpu *vcpu, struct vgic_irq *irq) +{ + return (vgic_irq_is_sgi(irq->intid) && + vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2); +} + void vgic_mmio_write_spending(struct kvm_vcpu *vcpu, gpa_t addr, unsigned int len, unsigned long val) @@ -207,6 +213,12 @@ void vgic_mmio_write_spending(struct kvm for_each_set_bit(i, &val, len * 8) { struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+ /* GICD_ISPENDR0 SGI bits are WI */ + if (is_vgic_v2_sgi(vcpu, irq)) { + vgic_put_irq(vcpu->kvm, irq); + continue; + } + raw_spin_lock_irqsave(&irq->irq_lock, flags); if (irq->hw) vgic_hw_irq_spending(vcpu, irq, is_uaccess); @@ -254,6 +266,12 @@ void vgic_mmio_write_cpending(struct kvm for_each_set_bit(i, &val, len * 8) { struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+ /* GICD_ICPENDR0 SGI bits are WI */ + if (is_vgic_v2_sgi(vcpu, irq)) { + vgic_put_irq(vcpu->kvm, irq); + continue; + } + raw_spin_lock_irqsave(&irq->irq_lock, flags);
if (irq->hw) --- a/virt/kvm/arm/vgic/vgic-v2.c +++ b/virt/kvm/arm/vgic/vgic-v2.c @@ -184,7 +184,10 @@ void vgic_v2_populate_lr(struct kvm_vcpu if (vgic_irq_is_sgi(irq->intid)) { u32 src = ffs(irq->source);
- BUG_ON(!src); + if (WARN_RATELIMIT(!src, "No SGI source for INTID %d\n", + irq->intid)) + return; + val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT; irq->source &= ~(1 << (src - 1)); if (irq->source) { --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -167,7 +167,10 @@ void vgic_v3_populate_lr(struct kvm_vcpu model == KVM_DEV_TYPE_ARM_VGIC_V2) { u32 src = ffs(irq->source);
- BUG_ON(!src); + if (WARN_RATELIMIT(!src, "No SGI source for INTID %d\n", + irq->intid)) + return; + val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT; irq->source &= ~(1 << (src - 1)); if (irq->source) {