[PATCH] KVM: VMX: Fix repeatly allocate of apic access page

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

[-- Attachment #1: Type: text/plain, Size: 1526 bytes --]

From 05164d73994a88ae130a086b592cd127c15a617f Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Tue, 6 Nov 2007 11:37:44 +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/vmx.c |   14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 42e7fad..6670e2b 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -1463,18 +1463,24 @@ static void seg_setup(int seg)
 static int alloc_apic_access_page(struct kvm *kvm)
 {
 	struct kvm_userspace_memory_region kvm_userspace_mem;
-	int r;
+	int r = 0;
 
-	r = -EFAULT;
+	mutex_lock(&kvm->lock);
+	if (kvm->apic_access_page)
+		goto out;
+	mutex_unlock(&kvm->lock);
 	kvm_userspace_mem.slot = APIC_ACCESS_PAGE_PRIVATE_MEMSLOT;
 	kvm_userspace_mem.flags = 0;
 	kvm_userspace_mem.guest_phys_addr = 0xfee00000ULL;
 	kvm_userspace_mem.memory_size = PAGE_SIZE;
 	r = kvm_set_memory_region(kvm, &kvm_userspace_mem, 0);
 	if (r)
-		return r;
+		goto out;
+	mutex_lock(&kvm->lock);
 	kvm->apic_access_page = gfn_to_page(kvm, 0xfee00);
-	return 0;
+out:
+	mutex_unlock(&kvm->lock);
+	return r;
 }
 
 /*
-- 
1.5.2


[-- Attachment #2: 0001-KVM-VMX-Fix-repeatly-allocate-of-apic-access-page.patch --]
[-- Type: text/x-diff, Size: 1526 bytes --]

From 05164d73994a88ae130a086b592cd127c15a617f Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Tue, 6 Nov 2007 11:37:44 +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/vmx.c |   14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 42e7fad..6670e2b 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -1463,18 +1463,24 @@ static void seg_setup(int seg)
 static int alloc_apic_access_page(struct kvm *kvm)
 {
 	struct kvm_userspace_memory_region kvm_userspace_mem;
-	int r;
+	int r = 0;
 
-	r = -EFAULT;
+	mutex_lock(&kvm->lock);
+	if (kvm->apic_access_page)
+		goto out;
+	mutex_unlock(&kvm->lock);
 	kvm_userspace_mem.slot = APIC_ACCESS_PAGE_PRIVATE_MEMSLOT;
 	kvm_userspace_mem.flags = 0;
 	kvm_userspace_mem.guest_phys_addr = 0xfee00000ULL;
 	kvm_userspace_mem.memory_size = PAGE_SIZE;
 	r = kvm_set_memory_region(kvm, &kvm_userspace_mem, 0);
 	if (r)
-		return r;
+		goto out;
+	mutex_lock(&kvm->lock);
 	kvm->apic_access_page = gfn_to_page(kvm, 0xfee00);
-	return 0;
+out:
+	mutex_unlock(&kvm->lock);
+	return r;
 }
 
 /*
-- 
1.5.2


[-- Attachment #3: Type: text/plain, Size: 314 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
https://lists.sourceforge.net/lists/listinfo/kvm-devel