[PATCH] KVM: VMX: Fix repeatly calling alloc_apic_access_page()

[Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

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From 00a52112d813af983dd4d34cb7dc701f6fe88829 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Fri, 2 Nov 2007 11:56:17 +0800
Subject: [PATCH] KVM: VMX: Fix repeatly calling alloc_apic_access_page()

For SMP guest, alloc_apic_access_page() would be called more than once. So 
only the last vcpu's vmcs get correct apic access address, causing SMP guest 
can't benifit from FlexPriority.

This patch fixed this issue.

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
 drivers/kvm/kvm_main.c |    1 +
 drivers/kvm/vmx.c      |    5 ++++-
 2 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 34a681d..519626d 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -245,6 +245,7 @@ static struct kvm *kvm_create_vm(void)
 	spin_lock(&kvm_lock);
 	list_add(&kvm->vm_list, &vm_list);
 	spin_unlock(&kvm_lock);
+	kvm->apic_access_page = NULL;
 	return kvm;
 }
 
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 42e7fad..89007b2 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -1466,6 +1466,8 @@ static int alloc_apic_access_page(struct kvm *kvm)
 	int r;
 
 	r = -EFAULT;
+	if (kvm->apic_access_page)
+		return 0;
 	kvm_userspace_mem.slot = APIC_ACCESS_PAGE_PRIVATE_MEMSLOT;
 	kvm_userspace_mem.flags = 0;
 	kvm_userspace_mem.guest_phys_addr = 0xfee00000ULL;
@@ -1584,7 +1586,8 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 	vmcs_writel(CR0_GUEST_HOST_MASK, ~0UL);
 	vmcs_writel(CR4_GUEST_HOST_MASK, KVM_GUEST_CR4_MASK);
 
-	if (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))
+	if ((vmx->vcpu.vcpu_id == 0) &&
+	    (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm)))
 		if (alloc_apic_access_page(vmx->vcpu.kvm) != 0)
 			return -ENOMEM;
 
-- 
1.5.2


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From 00a52112d813af983dd4d34cb7dc701f6fe88829 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Fri, 2 Nov 2007 11:56:17 +0800
Subject: [PATCH] KVM: VMX: Fix repeatly allocate of apic access page

For SMP guest, alloc_apic_access_page() would be called more than once.
So only the last one works, causing SMP guest can't benifit from FlexPriority.

This patch fixed this issue.

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
 drivers/kvm/kvm_main.c |    1 +
 drivers/kvm/vmx.c      |    5 ++++-
 2 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 34a681d..519626d 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -245,6 +245,7 @@ static struct kvm *kvm_create_vm(void)
 	spin_lock(&kvm_lock);
 	list_add(&kvm->vm_list, &vm_list);
 	spin_unlock(&kvm_lock);
+	kvm->apic_access_page = NULL;
 	return kvm;
 }
 
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 42e7fad..89007b2 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -1466,6 +1466,8 @@ static int alloc_apic_access_page(struct kvm *kvm)
 	int r;
 
 	r = -EFAULT;
+	if (kvm->apic_access_page)
+		return 0;
 	kvm_userspace_mem.slot = APIC_ACCESS_PAGE_PRIVATE_MEMSLOT;
 	kvm_userspace_mem.flags = 0;
 	kvm_userspace_mem.guest_phys_addr = 0xfee00000ULL;
@@ -1584,7 +1586,8 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 	vmcs_writel(CR0_GUEST_HOST_MASK, ~0UL);
 	vmcs_writel(CR4_GUEST_HOST_MASK, KVM_GUEST_CR4_MASK);
 
-	if (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))
+	if ((vmx->vcpu.vcpu_id == 0) &&
+	    (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm)))
 		if (alloc_apic_access_page(vmx->vcpu.kvm) != 0)
 			return -ENOMEM;
 
-- 
1.5.2


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