dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

KVM: SVM: Fix lazy FPU switching 

If the guest writes to cr0 and leaves the TS flag at 0 while vcpu->fpu_active
is also 0, the TS flag in the guest's cr0 gets lost. This leads to corrupt FPU
state an causes Windows Vista 64bit to crash very soon after boot.  This patch
fixes this bug.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Joerg Roedel 2008-01-21 13:09:33 +01:00 committed by Avi Kivity
parent 038f2f7255
commit 334df50a86
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kvm/svm.c
View File

@ -792,6 +792,8 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
vcpu->arch.cr0 = cr0;
cr0 |= X86_CR0_PG | X86_CR0_WP;
cr0 &= ~(X86_CR0_CD | X86_CR0_NW);
if (!vcpu->fpu_active)
cr0 |= X86_CR0_TS;
svm->vmcb->save.cr0 = cr0;
}