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-rw-r--r--virt/kvm/arm/arch_timer.c81
-rw-r--r--virt/kvm/arm/vgic.c102
2 files changed, 82 insertions, 101 deletions
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 32095fbb5d7c..523816d8c402 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -59,18 +59,6 @@ static void timer_disarm(struct arch_timer_cpu *timer)
}
}
-static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu)
-{
- int ret;
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
-
- kvm_vgic_set_phys_irq_active(timer->map, true);
- ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id,
- timer->map,
- timer->irq->level);
- WARN_ON(ret);
-}
-
static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
{
struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id;
@@ -116,8 +104,7 @@ static bool kvm_timer_irq_can_fire(struct kvm_vcpu *vcpu)
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
return !(timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) &&
- (timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE) &&
- !kvm_vgic_get_phys_irq_active(timer->map);
+ (timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE);
}
bool kvm_timer_should_fire(struct kvm_vcpu *vcpu)
@@ -134,6 +121,41 @@ bool kvm_timer_should_fire(struct kvm_vcpu *vcpu)
return cval <= now;
}
+static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level)
+{
+ int ret;
+ struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
+
+ BUG_ON(!vgic_initialized(vcpu->kvm));
+
+ timer->irq.level = new_level;
+ ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id,
+ timer->map,
+ timer->irq.level);
+ WARN_ON(ret);
+}
+
+/*
+ * Check if there was a change in the timer state (should we raise or lower
+ * the line level to the GIC).
+ */
+static void kvm_timer_update_state(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
+
+ /*
+ * If userspace modified the timer registers via SET_ONE_REG before
+ * the vgic was initialized, we mustn't set the timer->irq.level value
+ * because the guest would never see the interrupt. Instead wait
+ * until we call this function from kvm_timer_flush_hwstate.
+ */
+ if (!vgic_initialized(vcpu->kvm))
+ return;
+
+ if (kvm_timer_should_fire(vcpu) != timer->irq.level)
+ kvm_timer_update_irq(vcpu, !timer->irq.level);
+}
+
/*
* Schedule the background timer before calling kvm_vcpu_block, so that this
* thread is removed from its waitqueue and made runnable when there's a timer
@@ -192,17 +214,20 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu)
bool phys_active;
int ret;
- if (kvm_timer_should_fire(vcpu))
- kvm_timer_inject_irq(vcpu);
+ kvm_timer_update_state(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 we enter the guest with the virtual input level to the VGIC
+ * asserted, then we have already told the VGIC what we need to, and
+ * we don't need to exit from the guest until the guest deactivates
+ * the already injected interrupt, so therefore we should set the
+ * hardware active state to prevent unnecessary exits from the guest.
+ *
+ * Conversely, if the virtual input level is deasserted, then always
+ * clear the hardware active state to ensure that hardware interrupts
+ * from the timer triggers a guest exit.
*/
- if (kvm_vgic_get_phys_irq_active(timer->map))
+ if (timer->irq.level)
phys_active = true;
else
phys_active = false;
@@ -226,8 +251,11 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
BUG_ON(timer_is_armed(timer));
- if (kvm_timer_should_fire(vcpu))
- kvm_timer_inject_irq(vcpu);
+ /*
+ * The guest could have modified the timer registers or the timer
+ * could have expired, update the timer state.
+ */
+ kvm_timer_update_state(vcpu);
}
int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
@@ -242,7 +270,7 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
* kvm_vcpu_set_target(). To handle this, we determine
* vcpu timer irq number when the vcpu is reset.
*/
- timer->irq = irq;
+ timer->irq.irq = irq->irq;
/*
* The bits in CNTV_CTL are architecturally reset to UNKNOWN for ARMv8
@@ -251,6 +279,7 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
* the ARMv7 architecture.
*/
timer->cntv_ctl = 0;
+ kvm_timer_update_state(vcpu);
/*
* Tell the VGIC that the virtual interrupt is tied to a
@@ -295,6 +324,8 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
default:
return -1;
}
+
+ kvm_timer_update_state(vcpu);
return 0;
}
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index a44ecf9eca4e..3c2909c1bda3 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -537,34 +537,6 @@ 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)
@@ -595,7 +567,6 @@ 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;
}
@@ -633,7 +604,6 @@ 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;
}
@@ -1443,29 +1413,37 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
/*
* Save the physical active state, and reset it to inactive.
*
- * Return 1 if HW interrupt went from active to inactive, and 0 otherwise.
+ * Return true if there's a pending level triggered interrupt line to queue.
*/
-static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr)
+static bool vgic_sync_hwirq(struct kvm_vcpu *vcpu, int lr, struct vgic_lr vlr)
{
+ struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
struct irq_phys_map *map;
+ bool phys_active;
+ bool level_pending;
int ret;
if (!(vlr.state & LR_HW))
- return 0;
+ return false;
map = vgic_irq_map_search(vcpu, vlr.irq);
BUG_ON(!map);
ret = irq_get_irqchip_state(map->irq,
IRQCHIP_STATE_ACTIVE,
- &map->active);
+ &phys_active);
WARN_ON(ret);
- if (map->active)
+ if (phys_active)
return 0;
- return 1;
+ /* Mapped edge-triggered interrupts not yet supported. */
+ WARN_ON(vgic_irq_is_edge(vcpu, vlr.irq));
+ spin_lock(&dist->lock);
+ level_pending = process_level_irq(vcpu, lr, vlr);
+ spin_unlock(&dist->lock);
+ return level_pending;
}
/* Sync back the VGIC state after a guest run */
@@ -1490,18 +1468,8 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
continue;
vlr = vgic_get_lr(vcpu, lr);
- if (vgic_sync_hwirq(vcpu, vlr)) {
- /*
- * So this is a HW interrupt that the guest
- * EOI-ed. Clean the LR state and allow the
- * interrupt to be sampled again.
- */
- vlr.state = 0;
- vlr.hwirq = 0;
- vgic_set_lr(vcpu, lr, vlr);
- vgic_irq_clear_queued(vcpu, vlr.irq);
- set_bit(lr, elrsr_ptr);
- }
+ if (vgic_sync_hwirq(vcpu, lr, vlr))
+ level_pending = true;
if (!test_bit(lr, elrsr_ptr))
continue;
@@ -1881,30 +1849,6 @@ static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu)
}
/**
- * kvm_vgic_get_phys_irq_active - Return the active state of a mapped IRQ
- *
- * Return the logical active state of a mapped interrupt. This doesn't
- * necessarily reflects the current HW state.
- */
-bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map)
-{
- BUG_ON(!map);
- return map->active;
-}
-
-/**
- * kvm_vgic_set_phys_irq_active - Set the active state of a mapped IRQ
- *
- * Set the logical active state of a mapped interrupt. This doesn't
- * immediately affects the HW state.
- */
-void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active)
-{
- BUG_ON(!map);
- map->active = active;
-}
-
-/**
* kvm_vgic_unmap_phys_irq - Remove a virtual to physical IRQ mapping
* @vcpu: The VCPU pointer
* @map: The pointer to a mapping obtained through kvm_vgic_map_phys_irq
@@ -2129,17 +2073,23 @@ int vgic_init(struct kvm *kvm)
}
/*
- * Enable all SGIs and configure all private IRQs as
- * edge-triggered.
+ * Enable and configure all SGIs to be edge-triggere and
+ * configure all PPIs as level-triggered.
*/
for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
- if (i < VGIC_NR_SGIS)
+ if (i < VGIC_NR_SGIS) {
+ /* SGIs */
vgic_bitmap_set_irq_val(&dist->irq_enabled,
vcpu->vcpu_id, i, 1);
- if (i < VGIC_NR_PRIVATE_IRQS)
vgic_bitmap_set_irq_val(&dist->irq_cfg,
vcpu->vcpu_id, i,
VGIC_CFG_EDGE);
+ } else if (i < VGIC_NR_PRIVATE_IRQS) {
+ /* PPIs */
+ vgic_bitmap_set_irq_val(&dist->irq_cfg,
+ vcpu->vcpu_id, i,
+ VGIC_CFG_LEVEL);
+ }
}
vgic_enable(vcpu);