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-rw-r--r--virt/kvm/arm/arch_timer.c19
-rw-r--r--virt/kvm/arm/vgic.c95
2 files changed, 74 insertions, 40 deletions
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 48c6e1ac6827..b9d3a32cbc04 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -137,6 +137,8 @@ bool kvm_timer_should_fire(struct kvm_vcpu *vcpu)
void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu)
{
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
+ bool phys_active;
+ int ret;
/*
* We're about to run this vcpu again, so there is no need to
@@ -151,6 +153,23 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu)
*/
if (kvm_timer_should_fire(vcpu))
kvm_timer_inject_irq(vcpu);
+
+ /*
+ * We keep track of whether the edge-triggered interrupt has been
+ * signalled to the vgic/guest, and if so, we mask the interrupt and
+ * the physical distributor to prevent the timer from raising a
+ * physical interrupt whenever we run a guest, preventing forward
+ * VCPU progress.
+ */
+ if (kvm_vgic_get_phys_irq_active(timer->map))
+ phys_active = true;
+ else
+ phys_active = false;
+
+ ret = irq_set_irqchip_state(timer->map->irq,
+ IRQCHIP_STATE_ACTIVE,
+ phys_active);
+ WARN_ON(ret);
}
/**
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 77b0176b0484..30489181922d 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -531,6 +531,34 @@ bool vgic_handle_set_pending_reg(struct kvm *kvm,
return false;
}
+/*
+ * If a mapped interrupt's state has been modified by the guest such that it
+ * is no longer active or pending, without it have gone through the sync path,
+ * then the map->active field must be cleared so the interrupt can be taken
+ * again.
+ */
+static void vgic_handle_clear_mapped_irq(struct kvm_vcpu *vcpu)
+{
+ struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+ struct list_head *root;
+ struct irq_phys_map_entry *entry;
+ struct irq_phys_map *map;
+
+ rcu_read_lock();
+
+ /* Check for PPIs */
+ root = &vgic_cpu->irq_phys_map_list;
+ list_for_each_entry_rcu(entry, root, entry) {
+ map = &entry->map;
+
+ if (!vgic_dist_irq_is_pending(vcpu, map->virt_irq) &&
+ !vgic_irq_is_active(vcpu, map->virt_irq))
+ map->active = false;
+ }
+
+ rcu_read_unlock();
+}
+
bool vgic_handle_clear_pending_reg(struct kvm *kvm,
struct kvm_exit_mmio *mmio,
phys_addr_t offset, int vcpu_id)
@@ -561,6 +589,7 @@ bool vgic_handle_clear_pending_reg(struct kvm *kvm,
vcpu_id, offset);
vgic_reg_access(mmio, reg, offset, mode);
+ vgic_handle_clear_mapped_irq(kvm_get_vcpu(kvm, vcpu_id));
vgic_update_state(kvm);
return true;
}
@@ -598,6 +627,7 @@ bool vgic_handle_clear_active_reg(struct kvm *kvm,
ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
if (mmio->is_write) {
+ vgic_handle_clear_mapped_irq(kvm_get_vcpu(kvm, vcpu_id));
vgic_update_state(kvm);
return true;
}
@@ -982,6 +1012,12 @@ static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
pend_shared = vcpu->arch.vgic_cpu.pending_shared;
+ if (!dist->enabled) {
+ bitmap_zero(pend_percpu, VGIC_NR_PRIVATE_IRQS);
+ bitmap_zero(pend_shared, nr_shared);
+ return 0;
+ }
+
pending = vgic_bitmap_get_cpu_map(&dist->irq_pending, vcpu_id);
enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
@@ -1009,11 +1045,6 @@ void vgic_update_state(struct kvm *kvm)
struct kvm_vcpu *vcpu;
int c;
- if (!dist->enabled) {
- set_bit(0, dist->irq_pending_on_cpu);
- return;
- }
-
kvm_for_each_vcpu(c, vcpu, kvm) {
if (compute_pending_for_cpu(vcpu))
set_bit(c, dist->irq_pending_on_cpu);
@@ -1092,6 +1123,15 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr);
+ /*
+ * We must transfer the pending state back to the distributor before
+ * retiring the LR, otherwise we may loose edge-triggered interrupts.
+ */
+ if (vlr.state & LR_STATE_PENDING) {
+ vgic_dist_irq_set_pending(vcpu, irq);
+ vlr.hwirq = 0;
+ }
+
vlr.state = 0;
vgic_set_lr(vcpu, lr_nr, vlr);
clear_bit(lr_nr, vgic_cpu->lr_used);
@@ -1132,7 +1172,8 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq,
kvm_debug("Set active, clear distributor: 0x%x\n", vlr.state);
vgic_irq_clear_active(vcpu, irq);
vgic_update_state(vcpu->kvm);
- } else if (vgic_dist_irq_is_pending(vcpu, irq)) {
+ } else {
+ WARN_ON(!vgic_dist_irq_is_pending(vcpu, irq));
vlr.state |= LR_STATE_PENDING;
kvm_debug("Set pending: 0x%x\n", vlr.state);
}
@@ -1240,7 +1281,7 @@ static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long *pa_percpu, *pa_shared;
- int i, vcpu_id, lr, ret;
+ int i, vcpu_id;
int overflow = 0;
int nr_shared = vgic_nr_shared_irqs(dist);
@@ -1295,31 +1336,6 @@ epilog:
*/
clear_bit(vcpu_id, dist->irq_pending_on_cpu);
}
-
- for (lr = 0; lr < vgic->nr_lr; lr++) {
- struct vgic_lr vlr;
-
- if (!test_bit(lr, vgic_cpu->lr_used))
- continue;
-
- vlr = vgic_get_lr(vcpu, lr);
-
- /*
- * If we have a mapping, and the virtual interrupt is
- * presented to the guest (as pending or active), then we must
- * set the state to active in the physical world. See
- * Documentation/virtual/kvm/arm/vgic-mapped-irqs.txt.
- */
- if (vlr.state & LR_HW) {
- struct irq_phys_map *map;
- map = vgic_irq_map_search(vcpu, vlr.irq);
-
- ret = irq_set_irqchip_state(map->irq,
- IRQCHIP_STATE_ACTIVE,
- true);
- WARN_ON(ret);
- }
- }
}
static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
@@ -1421,7 +1437,7 @@ static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr)
return 0;
map = vgic_irq_map_search(vcpu, vlr.irq);
- BUG_ON(!map || !map->active);
+ BUG_ON(!map);
ret = irq_get_irqchip_state(map->irq,
IRQCHIP_STATE_ACTIVE,
@@ -1429,13 +1445,8 @@ static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr)
WARN_ON(ret);
- if (map->active) {
- ret = irq_set_irqchip_state(map->irq,
- IRQCHIP_STATE_ACTIVE,
- false);
- WARN_ON(ret);
+ if (map->active)
return 0;
- }
return 1;
}
@@ -1607,8 +1618,12 @@ static int vgic_update_irq_pending(struct kvm *kvm, int cpuid,
} else {
if (level_triggered) {
vgic_dist_irq_clear_level(vcpu, irq_num);
- if (!vgic_dist_irq_soft_pend(vcpu, irq_num))
+ if (!vgic_dist_irq_soft_pend(vcpu, irq_num)) {
vgic_dist_irq_clear_pending(vcpu, irq_num);
+ vgic_cpu_irq_clear(vcpu, irq_num);
+ if (!compute_pending_for_cpu(vcpu))
+ clear_bit(cpuid, dist->irq_pending_on_cpu);
+ }
}
ret = false;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-25 08:51:35 +0000