[patch 23/60] KVM: SVM: Fix FPU leak while emulating clts

Greg KH
2007-12-13T07:05:31Z

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2.6.23-stable review patch. If anyone has any objections, please let us
know.

------------------
From: Amit Shah <amit.shah@qumranet.com>

patch 404fb881b82cf0cf6981832f8d31a7484e4dee81 in mainline.

The clts code didn't use set_cr0 properly, so our lazy FPU
processing wasn't being done by the clts instruction at all.

(this isn't called on Intel as the hardware does the decode for us)

Signed-off-by: Amit Shah <amit.shah@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/kvm/kvm_main.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1163,10 +1163,7 @@ int emulate_invlpg(struct kvm_vcpu *vcpu

int emulate_clts(struct kvm_vcpu *vcpu)
{
- unsigned long cr0;
-
- cr0 = vcpu->cr0 & ~CR0_TS_MASK;
- kvm_arch_ops->set_cr0(vcpu, cr0);
+ kvm_arch_ops->set_cr0(vcpu, vcpu->cr0 & ~X86_CR0_TS);
return X86EMUL_CONTINUE;
}

--