Sorry, I was a bit inaccurate in my thoughts at Fri about necessary
amount of work, patch lays perfectly on 3.10 with bit of monkey
rewrites. The attached one fixed problem for me - it represents
0b10a1c87a2b0fb459baaefba9cb163dbb8d3344,
0bc830b05c667218d703f2026ec866c49df974fc,
44847dea79751e95665a439f8c63a65e51da8e1f and
673f7b4257a1fe7b181e1a1182ecc2b6b2b795f1.
diff -ru linux-3.10.11/arch/ia64/kvm/kvm-ia64.c linux-3.10.11.patched-ioapic/arch/ia64/kvm/kvm-ia64.c
--- linux-3.10.11/arch/ia64/kvm/kvm-ia64.c 2013-09-08 09:10:14.000000000 +0400
+++ linux-3.10.11.patched-ioapic/arch/ia64/kvm/kvm-ia64.c 2014-08-24 19:49:25.723072383 +0400
@@ -199,6 +199,7 @@
case KVM_CAP_IRQCHIP:
case KVM_CAP_MP_STATE:
case KVM_CAP_IRQ_INJECT_STATUS:
+ case KVM_CAP_IOAPIC_POLARITY_IGNORED:
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
diff -ru linux-3.10.11/arch/x86/kvm/x86.c linux-3.10.11.patched-ioapic/arch/x86/kvm/x86.c
--- linux-3.10.11/arch/x86/kvm/x86.c 2013-09-08 09:10:14.000000000 +0400
+++ linux-3.10.11.patched-ioapic/arch/x86/kvm/x86.c 2014-08-24 19:50:06.553716276 +0400
@@ -2537,6 +2537,7 @@
case KVM_CAP_GET_TSC_KHZ:
case KVM_CAP_KVMCLOCK_CTRL:
case KVM_CAP_READONLY_MEM:
+ case KVM_CAP_IOAPIC_POLARITY_IGNORED:
#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT
case KVM_CAP_ASSIGN_DEV_IRQ:
case KVM_CAP_PCI_2_3:
diff -ru linux-3.10.11/include/uapi/linux/kvm.h linux-3.10.11.patched-ioapic/include/uapi/linux/kvm.h
--- linux-3.10.11/include/uapi/linux/kvm.h 2013-09-08 09:10:14.000000000 +0400
+++ linux-3.10.11.patched-ioapic/include/uapi/linux/kvm.h 2014-08-24 19:51:10.975577204 +0400
@@ -666,6 +666,7 @@
#define KVM_CAP_IRQ_MPIC 90
#define KVM_CAP_PPC_RTAS 91
#define KVM_CAP_IRQ_XICS 92
+#define KVM_CAP_IOAPIC_POLARITY_IGNORED 93
#ifdef KVM_CAP_IRQ_ROUTING
diff -ru linux-3.10.11/virt/kvm/ioapic.c linux-3.10.11.patched-ioapic/virt/kvm/ioapic.c
--- linux-3.10.11/virt/kvm/ioapic.c 2013-09-08 09:10:14.000000000 +0400
+++ linux-3.10.11.patched-ioapic/virt/kvm/ioapic.c 2014-08-24 19:59:26.755137527 +0400
@@ -50,7 +50,7 @@
#else
#define ioapic_debug(fmt, arg...)
#endif
-static int ioapic_deliver(struct kvm_ioapic *vioapic, int irq,
+static int ioapic_service(struct kvm_ioapic *vioapic, int irq
bool line_status);
static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
@@ -163,23 +163,67 @@
return false;
}
-static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx,
- bool line_status)
+static int ioapic_set_irq(struct kvm_ioapic *ioapic, unsigned int irq,
+ int irq_level, bool line_status)
{
- union kvm_ioapic_redirect_entry *pent;
- int injected = -1;
+ union kvm_ioapic_redirect_entry entry;
+ u32 mask = 1 << irq;
+ u32 old_irr;
+ int edge, ret;
- pent = &ioapic->redirtbl[idx];
+ entry = ioapic->redirtbl[irq];
+ edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
- if (!pent->fields.mask) {
- injected = ioapic_deliver(ioapic, idx, line_status);
- if (injected && pent->fields.trig_mode == IOAPIC_LEVEL_TRIG)
- pent->fields.remote_irr = 1;
+ if (!irq_level) {
+ ioapic->irr &= ~mask;
+ ret = 1;
+ goto out;
+ }
+
+ /*
+ * Return 0 for coalesced interrupts; for edge-triggered interrupts,
+ * this only happens if a previous edge has not been delivered due
+ * do masking. For level interrupts, the remote_irr field tells
+ * us if the interrupt is waiting for an EOI.
+ *
+ * RTC is special: it is edge-triggered, but userspace likes to know
+ * if it has been already ack-ed via EOI because coalesced RTC
+ * interrupts lead to time drift in Windows guests. So we track
+ * EOI manually for the RTC interrupt.
+ */
+ if (irq == RTC_GSI && line_status &&
+ rtc_irq_check_coalesced(ioapic)) {
+ ret = 0;
+ goto out;
}
- return injected;
+ old_irr = ioapic->irr;
+ ioapic->irr |= mask;
+ if ((edge && old_irr == ioapic->irr) ||
+ (!edge && entry.fields.remote_irr)) {
+ ret = 0;
+ goto out;
+ }
+
+ ret = ioapic_service(ioapic, irq, line_status);
+
+out:
+ trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
+ return ret;
+}
+
+static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
+{
+ u32 idx;
+
+ rtc_irq_eoi_tracking_reset(ioapic);
+ for_each_set_bit(idx, &irr, IOAPIC_NUM_PINS)
+ ioapic_set_irq(ioapic, idx, 1, true);
+
+ kvm_rtc_eoi_tracking_restore_all(ioapic);
}
+
static void update_handled_vectors(struct kvm_ioapic *ioapic)
{
DECLARE_BITMAP(handled_vectors, 256);
@@ -282,12 +326,15 @@
}
}
-static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq, bool line_status)
+static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
{
union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
struct kvm_lapic_irq irqe;
int ret;
+ if (entry->fields.mask)
+ return -1;
+
ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
"vector=%x trig_mode=%x\n",
entry->fields.dest_id, entry->fields.dest_mode,
@@ -302,6 +349,10 @@
irqe.level = 1;
irqe.shorthand = 0;
+ if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
+ ioapic->irr &= ~(1 << irq);
+
+
if (irq == RTC_GSI && line_status) {
BUG_ON(ioapic->rtc_status.pending_eoi != 0);
ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe,
@@ -309,6 +360,8 @@
ioapic->rtc_status.pending_eoi = ret;
} else
ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe, NULL);
+ if (ret && irqe.trig_mode == IOAPIC_LEVEL_TRIG)
+ entry->fields.remote_irr = 1;
return ret;
}
@@ -316,39 +369,15 @@
int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
int level, bool line_status)
{
- u32 old_irr;
- u32 mask = 1 << irq;
- union kvm_ioapic_redirect_entry entry;
int ret, irq_level;
BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
spin_lock(&ioapic->lock);
- old_irr = ioapic->irr;
irq_level = __kvm_irq_line_state(&ioapic->irq_states[irq],
irq_source_id, level);
- entry = ioapic->redirtbl[irq];
- irq_level ^= entry.fields.polarity;
- if (!irq_level) {
- ioapic->irr &= ~mask;
- ret = 1;
- } else {
- int edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
+ ret = ioapic_set_irq(ioapic, irq, irq_level, line_status);
- if (irq == RTC_GSI && line_status &&
- rtc_irq_check_coalesced(ioapic)) {
- ret = 0; /* coalesced */
- goto out;
- }
- ioapic->irr |= mask;
- if ((edge && old_irr != ioapic->irr) ||
- (!edge && !entry.fields.remote_irr))
- ret = ioapic_service(ioapic, irq, line_status);
- else
- ret = 0; /* report coalesced interrupt */
- }
-out:
- trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
spin_unlock(&ioapic->lock);
return ret;
@@ -394,7 +423,7 @@
ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
ent->fields.remote_irr = 0;
- if (!ent->fields.mask && (ioapic->irr & (1 << i)))
+ if (ioapic->irr & (1 << i))
ioapic_service(ioapic, i, false);
}
}
@@ -595,9 +624,10 @@
spin_lock(&ioapic->lock);
memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
+ ioapic->irr = 0;
update_handled_vectors(ioapic);
kvm_vcpu_request_scan_ioapic(kvm);
- kvm_rtc_eoi_tracking_restore_all(ioapic);
+ kvm_ioapic_inject_all(ioapic, state->irr);
spin_unlock(&ioapic->lock);
return 0;
}
