[PATCH 0/2] Fix xsave/xcr save/restore memory leak

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* [PATCH 0/2] Fix xsave/xcr save/restore memory leak
@ 2010-06-20 13:14 Avi Kivity
  2010-06-20 13:14 ` [PATCH 1/2] KVM: Fix xsave and xcr " Avi Kivity
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Avi Kivity @ 2010-06-20 13:14 UTC (permalink / raw)
  To: Marcelo Tosatti, Sheng Yang; +Cc: kvm

There's a small leak in xsave/xcr save/restore that rapidly drains all memory
during Windows XP install without FlexPriority, since that triggers qemu
register reload frequently.

Avi Kivity (2):
  KVM: Fix xsave and xcr save/restore memory leak
  KVM: Consolidate load/save temporary buffer allocation and freeing

 arch/x86/kvm/x86.c |   66 +++++++++++++++++++++++++--------------------------
 1 files changed, 32 insertions(+), 34 deletions(-)


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH 1/2] KVM: Fix xsave and xcr save/restore memory leak
  2010-06-20 13:14 [PATCH 0/2] Fix xsave/xcr save/restore memory leak Avi Kivity
@ 2010-06-20 13:14 ` Avi Kivity
  2010-06-20 13:14 ` [PATCH 2/2] KVM: Consolidate load/save temporary buffer allocation and freeing Avi Kivity
  2010-06-21  1:09 ` [PATCH 0/2] Fix xsave/xcr save/restore memory leak Sheng Yang
  2 siblings, 0 replies; 4+ messages in thread
From: Avi Kivity @ 2010-06-20 13:14 UTC (permalink / raw)
  To: Marcelo Tosatti, Sheng Yang; +Cc: kvm

We allocate temporary kernel buffers for these structures, but never free them.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/x86.c |   12 ++++--------
 1 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d3d008e..d513e57 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2437,6 +2437,8 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	void __user *argp = (void __user *)arg;
 	int r;
 	struct kvm_lapic_state *lapic = NULL;
+	struct kvm_xsave *xsave = NULL;
+	struct kvm_xcrs *xcrs = NULL;
 
 	switch (ioctl) {
 	case KVM_GET_LAPIC: {
@@ -2632,8 +2634,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_GET_XSAVE: {
-		struct kvm_xsave *xsave;
-
 		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xsave)
@@ -2648,8 +2648,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_SET_XSAVE: {
-		struct kvm_xsave *xsave;
-
 		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xsave)
@@ -2663,8 +2661,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_GET_XCRS: {
-		struct kvm_xcrs *xcrs;
-
 		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xcrs)
@@ -2680,8 +2676,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_SET_XCRS: {
-		struct kvm_xcrs *xcrs;
-
 		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xcrs)
@@ -2700,6 +2694,8 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	}
 out:
 	kfree(lapic);
+	kfree(xsave);
+	kfree(xcrs);
 	return r;
 }
 
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH 2/2] KVM: Consolidate load/save temporary buffer allocation and freeing
  2010-06-20 13:14 [PATCH 0/2] Fix xsave/xcr save/restore memory leak Avi Kivity
  2010-06-20 13:14 ` [PATCH 1/2] KVM: Fix xsave and xcr " Avi Kivity
@ 2010-06-20 13:14 ` Avi Kivity
  2010-06-21  1:09 ` [PATCH 0/2] Fix xsave/xcr save/restore memory leak Sheng Yang
  2 siblings, 0 replies; 4+ messages in thread
From: Avi Kivity @ 2010-06-20 13:14 UTC (permalink / raw)
  To: Marcelo Tosatti, Sheng Yang; +Cc: kvm

Instead of three temporary variables and three free calls, have one temporary
variable (with four names) and one free call.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/x86.c |   64 ++++++++++++++++++++++++++-------------------------
 1 files changed, 33 insertions(+), 31 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d513e57..33156a3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2436,25 +2436,29 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	struct kvm_vcpu *vcpu = filp->private_data;
 	void __user *argp = (void __user *)arg;
 	int r;
-	struct kvm_lapic_state *lapic = NULL;
-	struct kvm_xsave *xsave = NULL;
-	struct kvm_xcrs *xcrs = NULL;
+	union {
+		struct kvm_lapic_state *lapic;
+		struct kvm_xsave *xsave;
+		struct kvm_xcrs *xcrs;
+		void *buffer;
+	} u;
 
+	u.buffer = NULL;
 	switch (ioctl) {
 	case KVM_GET_LAPIC: {
 		r = -EINVAL;
 		if (!vcpu->arch.apic)
 			goto out;
-		lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
+		u.lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
 
 		r = -ENOMEM;
-		if (!lapic)
+		if (!u.lapic)
 			goto out;
-		r = kvm_vcpu_ioctl_get_lapic(vcpu, lapic);
+		r = kvm_vcpu_ioctl_get_lapic(vcpu, u.lapic);
 		if (r)
 			goto out;
 		r = -EFAULT;
-		if (copy_to_user(argp, lapic, sizeof(struct kvm_lapic_state)))
+		if (copy_to_user(argp, u.lapic, sizeof(struct kvm_lapic_state)))
 			goto out;
 		r = 0;
 		break;
@@ -2463,14 +2467,14 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		r = -EINVAL;
 		if (!vcpu->arch.apic)
 			goto out;
-		lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
+		u.lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
 		r = -ENOMEM;
-		if (!lapic)
+		if (!u.lapic)
 			goto out;
 		r = -EFAULT;
-		if (copy_from_user(lapic, argp, sizeof(struct kvm_lapic_state)))
+		if (copy_from_user(u.lapic, argp, sizeof(struct kvm_lapic_state)))
 			goto out;
-		r = kvm_vcpu_ioctl_set_lapic(vcpu, lapic);
+		r = kvm_vcpu_ioctl_set_lapic(vcpu, u.lapic);
 		if (r)
 			goto out;
 		r = 0;
@@ -2634,68 +2638,66 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_GET_XSAVE: {
-		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
+		u.xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
-		if (!xsave)
+		if (!u.xsave)
 			break;
 
-		kvm_vcpu_ioctl_x86_get_xsave(vcpu, xsave);
+		kvm_vcpu_ioctl_x86_get_xsave(vcpu, u.xsave);
 
 		r = -EFAULT;
-		if (copy_to_user(argp, xsave, sizeof(struct kvm_xsave)))
+		if (copy_to_user(argp, u.xsave, sizeof(struct kvm_xsave)))
 			break;
 		r = 0;
 		break;
 	}
 	case KVM_SET_XSAVE: {
-		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
+		u.xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
-		if (!xsave)
+		if (!u.xsave)
 			break;
 
 		r = -EFAULT;
-		if (copy_from_user(xsave, argp, sizeof(struct kvm_xsave)))
+		if (copy_from_user(u.xsave, argp, sizeof(struct kvm_xsave)))
 			break;
 
-		r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, xsave);
+		r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, u.xsave);
 		break;
 	}
 	case KVM_GET_XCRS: {
-		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
+		u.xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
-		if (!xcrs)
+		if (!u.xcrs)
 			break;
 
-		kvm_vcpu_ioctl_x86_get_xcrs(vcpu, xcrs);
+		kvm_vcpu_ioctl_x86_get_xcrs(vcpu, u.xcrs);
 
 		r = -EFAULT;
-		if (copy_to_user(argp, xcrs,
+		if (copy_to_user(argp, u.xcrs,
 				 sizeof(struct kvm_xcrs)))
 			break;
 		r = 0;
 		break;
 	}
 	case KVM_SET_XCRS: {
-		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
+		u.xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
-		if (!xcrs)
+		if (!u.xcrs)
 			break;
 
 		r = -EFAULT;
-		if (copy_from_user(xcrs, argp,
+		if (copy_from_user(u.xcrs, argp,
 				   sizeof(struct kvm_xcrs)))
 			break;
 
-		r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, xcrs);
+		r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, u.xcrs);
 		break;
 	}
 	default:
 		r = -EINVAL;
 	}
 out:
-	kfree(lapic);
-	kfree(xsave);
-	kfree(xcrs);
+	kfree(u.buffer);
 	return r;
 }
 
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH 0/2] Fix xsave/xcr save/restore memory leak
  2010-06-20 13:14 [PATCH 0/2] Fix xsave/xcr save/restore memory leak Avi Kivity
  2010-06-20 13:14 ` [PATCH 1/2] KVM: Fix xsave and xcr " Avi Kivity
  2010-06-20 13:14 ` [PATCH 2/2] KVM: Consolidate load/save temporary buffer allocation and freeing Avi Kivity
@ 2010-06-21  1:09 ` Sheng Yang
  2 siblings, 0 replies; 4+ messages in thread
From: Sheng Yang @ 2010-06-21  1:09 UTC (permalink / raw)
  To: Avi Kivity; +Cc: Marcelo Tosatti, kvm

On Sunday 20 June 2010 21:14:11 Avi Kivity wrote:
> There's a small leak in xsave/xcr save/restore that rapidly drains all
> memory during Windows XP install without FlexPriority, since that triggers
> qemu register reload frequently.

Oops...

Would be more careful next time...

--
regards
Yang, Sheng

> 
> Avi Kivity (2):
>   KVM: Fix xsave and xcr save/restore memory leak
>   KVM: Consolidate load/save temporary buffer allocation and freeing
> 
>  arch/x86/kvm/x86.c |   66
> +++++++++++++++++++++++++-------------------------- 1 files changed, 32
> insertions(+), 34 deletions(-)

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2010-06-21  1:09 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2010-06-20 13:14 [PATCH 0/2] Fix xsave/xcr save/restore memory leak Avi Kivity
2010-06-20 13:14 ` [PATCH 1/2] KVM: Fix xsave and xcr " Avi Kivity
2010-06-20 13:14 ` [PATCH 2/2] KVM: Consolidate load/save temporary buffer allocation and freeing Avi Kivity
2010-06-21  1:09 ` [PATCH 0/2] Fix xsave/xcr save/restore memory leak Sheng Yang

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