From 42604bd5e49d6e0da79e42041b29fb1b07f91bd7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sun, 17 Dec 2023 11:15:09 +0000 Subject: [PATCH] KVM: arm64: vgic-v4: Restore pending state on host userspace write commit 7b95382f965133ef61ce44aaabc518c16eb46909 upstream. When the VMM writes to ISPENDR0 to set the state pending state of an SGI, we fail to convey this to the HW if this SGI is already backed by a GICv4.1 vSGI. This is a bit of a corner case, as this would only occur if the vgic state is changed on an already running VM, but this can apparently happen across a guest reset driven by the VMM. Fix this by always writing out the pending_latch value to the HW, and reseting it to false. Reported-by: Kunkun Jiang Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Cc: stable@vger.kernel.org # 5.10+ Link: https://lore.kernel.org/r/7e7f2c0c-448b-10a9-8929-4b8f4f6e2a32@huawei.com Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kvm/vgic/vgic-mmio-v3.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/vgic/vgic-mmio-v3.c b/arch/arm64/kvm/vgic/vgic-mmio-v3.c index 871a45d..ae5a3a7 100644 --- a/arch/arm64/kvm/vgic/vgic-mmio-v3.c +++ b/arch/arm64/kvm/vgic/vgic-mmio-v3.c @@ -365,19 +365,26 @@ static int vgic_v3_uaccess_write_pending(struct kvm_vcpu *vcpu, struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); raw_spin_lock_irqsave(&irq->irq_lock, flags); - if (test_bit(i, &val)) { - /* - * pending_latch is set irrespective of irq type - * (level or edge) to avoid dependency that VM should - * restore irq config before pending info. - */ - irq->pending_latch = true; - vgic_queue_irq_unlock(vcpu->kvm, irq, flags); - } else { + + /* + * pending_latch is set irrespective of irq type + * (level or edge) to avoid dependency that VM should + * restore irq config before pending info. + */ + irq->pending_latch = test_bit(i, &val); + + if (irq->hw && vgic_irq_is_sgi(irq->intid)) { + irq_set_irqchip_state(irq->host_irq, + IRQCHIP_STATE_PENDING, + irq->pending_latch); irq->pending_latch = false; - raw_spin_unlock_irqrestore(&irq->irq_lock, flags); } + if (irq->pending_latch) + vgic_queue_irq_unlock(vcpu->kvm, irq, flags); + else + raw_spin_unlock_irqrestore(&irq->irq_lock, flags); + vgic_put_irq(vcpu->kvm, irq); } -- 2.7.4