[PATCH] KVM: AMD SVM: Save and restore the floating point unit state

Fixes sf bug 1614113 (segfaults in nbench).

Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 3bf2579..59c930f 100644 (file)
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -575,6 +575,8 @@ static int svm_create_vcpu(struct kvm_vcpu *vcpu)
        memset(vcpu->svm->db_regs, 0, sizeof(vcpu->svm->db_regs));
        init_vmcb(vcpu->svm->vmcb);
 
+       fx_init(vcpu);
+
        return 0;
 
 out2:
@@ -1387,6 +1389,10 @@ again:
                save_db_regs(vcpu->svm->host_db_regs);
                load_db_regs(vcpu->svm->db_regs);
        }
+
+       fx_save(vcpu->host_fx_image);
+       fx_restore(vcpu->guest_fx_image);
+
        asm volatile (
 #ifdef CONFIG_X86_64
                "push %%rbx; push %%rcx; push %%rdx;"
@@ -1496,6 +1502,9 @@ again:
 #endif
                : "cc", "memory" );
 
+       fx_save(vcpu->guest_fx_image);
+       fx_restore(vcpu->host_fx_image);
+
        if ((vcpu->svm->vmcb->save.dr7 & 0xff))
                load_db_regs(vcpu->svm->host_db_regs);