From f358a4b235e54b14ea1fb58aa80b2509bfa31d21 Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Thu, 3 Sep 2009 13:43:57 -0300
Subject: [PATCH 1/3] Backport 44882eed2ebe7f75f8cdae5671ab1d6e0fa40dbc

Message-id: <20090804175630.GB3751@redhat.com>
RH-Author: Michael S. Tsirkin <mst@redhat.com>
Patchwork-id: 3156
O-Subject: [PATCH 1/3] Backport 44882eed2ebe7f75f8cdae5671ab1d6e0fa40dbc
Bugzilla: 515549
CVE:
RH-Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
RH-Acked-by: Juan Quintela <quintela@redhat.com>
RH-Acked-by: Gleb Natapov <gleb@redhat.com>
RH-Acked-by: Don Dutile <ddutile@redhat.com>

Backport this commit:
	commit 44882eed2ebe7f75f8cdae5671ab1d6e0fa40dbc
	Author: Marcelo Tosatti <mtosatti@redhat.com>
	Date:   Tue Jan 27 15:12:38 2009 -0200

	    KVM: make irq ack notifications aware of routing table

	    IRQ ack notifications assume an identity mapping between pin->gsi,
	    which might not be the case with, for example, HPET.

	    Translate before acking.

	    Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
	    Acked-by: Gleb Natapov <gleb@redhat.com>

without it, 5.4 userspace/kernel api is different between
upstream kernel and 5.4 kernel, which breaks qemu-kvm upstream.
https://bugzilla.redhat.com/show_bug.cgi?id=515549

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 arch/x86/kvm/i8259.c     |    5 +++--
 arch/x86/kvm/irq.h       |    2 ++
 include/linux/kvm_host.h |    2 +-
 virt/kvm/ioapic.c        |   10 +++++-----
 virt/kvm/irq_comm.c      |   13 ++++++++++---
 5 files changed, 21 insertions(+), 11 deletions(-)

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 arch/x86/kvm/i8259.c     |    5 +++--
 arch/x86/kvm/irq.h       |    2 ++
 include/linux/kvm_host.h |    2 +-
 virt/kvm/ioapic.c        |   10 +++++-----
 virt/kvm/irq_comm.c      |   13 ++++++++++---
 5 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 2752016..b4e662e 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -49,7 +49,8 @@ static void pic_unlock(struct kvm_pic *s)
 	spin_unlock(&s->lock);
 
 	while (acks) {
-		kvm_notify_acked_irq(kvm, __ffs(acks));
+		kvm_notify_acked_irq(kvm, SELECT_PIC(__ffs(acks)),
+				     __ffs(acks));
 		acks &= acks - 1;
 	}
 
@@ -240,7 +241,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
 	}
 	pic_update_irq(s);
 	pic_unlock(s);
-	kvm_notify_acked_irq(kvm, irq);
+	kvm_notify_acked_irq(kvm, SELECT_PIC(irq), irq);
 
 	return intno;
 }
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 82579ee..9f59318 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -32,6 +32,8 @@
 #include "lapic.h"
 
 #define PIC_NUM_PINS 16
+#define SELECT_PIC(irq) \
+	((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE)
 
 struct kvm;
 struct kvm_vcpu;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 0188088..84c08e8 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -365,7 +365,7 @@ void kvm_get_intr_delivery_bitmask(struct kvm_ioapic *ioapic,
 				   union kvm_ioapic_redirect_entry *entry,
 				   unsigned long *deliver_bitmask);
 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level);
-void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi);
+void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin);
 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian);
 void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian);
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 442915b..1e6a3a9 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -240,20 +240,20 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
 	return ret;
 }
 
-static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int gsi,
+static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int pin,
 				    int trigger_mode)
 {
 	union kvm_ioapic_redirect_entry *ent;
 
-	ent = &ioapic->redirtbl[gsi];
+	ent = &ioapic->redirtbl[pin];
 
-	kvm_notify_acked_irq(ioapic->kvm, gsi);
+	kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin);
 
 	if (trigger_mode == IOAPIC_LEVEL_TRIG) {
 		ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
 		ent->fields.remote_irr = 0;
-		if (!ent->fields.mask && (ioapic->irr & (1 << gsi)))
-			ioapic_service(ioapic, gsi);
+		if (!ent->fields.mask && (ioapic->irr & (1 << pin)))
+			ioapic_service(ioapic, pin);
 	}
 }
 
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index d86b0f3..5f50def 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -195,10 +195,19 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
 	return ret;
 }
 
-void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi)
+void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
 {
+	struct kvm_kernel_irq_routing_entry *e;
 	struct kvm_irq_ack_notifier *kian;
 	struct hlist_node *n;
+	unsigned gsi = pin;
+
+	list_for_each_entry(e, &kvm->irq_routing, link)
+		if (e->irqchip.irqchip == irqchip &&
+		    e->irqchip.pin == pin) {
+			gsi = e->gsi;
+			break;
+		}
 
 	hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
 		if (kian->gsi == gsi)
@@ -379,8 +388,6 @@ out:
 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 
 #ifdef CONFIG_X86
-#define SELECT_PIC(irq) \
-	((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE)
 #  define PIC_ROUTING_ENTRY(irq) \
 	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
 	  .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
-- 
1.6.3.rc4.29.g8146