@@ -108,11 +108,22 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
* If this causes us to lower the level, we have to also clear
* the physical active state, since we will otherwise never be
* told when the interrupt becomes asserted again.
+ *
+ * Another case is when the interrupt requires a helping hand
+ * on deactivation (no HW deactivation, for example).
*/
- if (vgic_irq_is_mapped_level(irq) && (val & GICH_LR_PENDING_BIT)) {
- irq->line_level = vgic_get_phys_line_level(irq);
+ if (vgic_irq_is_mapped_level(irq)) {
+ bool resample = false;
+
+ if (val & GICH_LR_PENDING_BIT) {
+ irq->line_level = vgic_get_phys_line_level(irq);
+ resample = !irq->line_level;
+ } else if (vgic_irq_needs_resampling(irq) &&
+ !(irq->active || irq->pending_latch)) {
+ resample = true;
+ }
- if (!irq->line_level)
+ if (resample)
vgic_irq_set_phys_active(irq, false);
}
@@ -152,7 +163,7 @@ void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
if (irq->group)
val |= GICH_LR_GROUP1;
- if (irq->hw) {
+ if (irq->hw && !vgic_irq_needs_resampling(irq)) {
val |= GICH_LR_HW;
val |= irq->hwintid << GICH_LR_PHYSID_CPUID_SHIFT;
/*
@@ -99,11 +99,22 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
* If this causes us to lower the level, we have to also clear
* the physical active state, since we will otherwise never be
* told when the interrupt becomes asserted again.
+ *
+ * Another case is when the interrupt requires a helping hand
+ * on deactivation (no HW deactivation, for example).
*/
- if (vgic_irq_is_mapped_level(irq) && (val & ICH_LR_PENDING_BIT)) {
- irq->line_level = vgic_get_phys_line_level(irq);
+ if (vgic_irq_is_mapped_level(irq)) {
+ bool resample = false;
+
+ if (val & ICH_LR_PENDING_BIT) {
+ irq->line_level = vgic_get_phys_line_level(irq);
+ resample = !irq->line_level;
+ } else if (vgic_irq_needs_resampling(irq) &&
+ !(irq->active || irq->pending_latch)) {
+ resample = true;
+ }
- if (!irq->line_level)
+ if (resample)
vgic_irq_set_phys_active(irq, false);
}
@@ -134,7 +145,7 @@ void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
}
}
- if (irq->hw) {
+ if (irq->hw && !vgic_irq_needs_resampling(irq)) {
val |= ICH_LR_HW;
val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
/*
@@ -99,6 +99,11 @@ enum vgic_irq_config {
* kvm_arm_get_running_vcpu() to get the vcpu pointer for private IRQs.
*/
struct irq_ops {
+ /* Per interrupt flags for special-cased interrupts */
+ unsigned long flags;
+
+#define VGIC_IRQ_SW_RESAMPLE BIT(0) /* Clear the active state for resampling */
+
/*
* Callback function pointer to in-kernel devices that can tell us the
* state of the input level of mapped level-triggered IRQ faster than
@@ -150,6 +155,11 @@ struct vgic_irq {
for in-kernel devices. */
};
+static inline bool vgic_irq_needs_resampling(struct vgic_irq *irq)
+{
+ return irq->ops && (irq->ops->flags & VGIC_IRQ_SW_RESAMPLE);
+}
+
struct vgic_register_region;
struct vgic_its;
In order to deal with these systems that do not offer HW-based deactivation of interrupts, let implement a SW-based approach: - When the irq is queued into a LR, treat it as a pure virtual interrupt and set the EOI flag in the LR. - When the interrupt state is read back from the LR, force a deactivation when the state is invalid (neither active nor pending) Interrupts requiring such treatment get the VGIC_SW_RESAMPLE flag. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/vgic/vgic-v2.c | 19 +++++++++++++++---- arch/arm64/kvm/vgic/vgic-v3.c | 19 +++++++++++++++---- include/kvm/arm_vgic.h | 10 ++++++++++ 3 files changed, 40 insertions(+), 8 deletions(-)