KVM: SVM: Restore unconditional cr0 intercept under npt
Currently we don't intercept cr0 at all when npt is enabled. This improves
performance but requires us to activate the fpu at all times.
Remove this behaviour in preparation for adding selective cr0 intercepts.
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 949990e..27273ed 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -643,10 +643,8 @@
control->intercept &= ~((1ULL << INTERCEPT_TASK_SWITCH) |
(1ULL << INTERCEPT_INVLPG));
control->intercept_exceptions &= ~(1 << PF_VECTOR);
- control->intercept_cr_read &= ~(INTERCEPT_CR0_MASK|
- INTERCEPT_CR3_MASK);
- control->intercept_cr_write &= ~(INTERCEPT_CR0_MASK|
- INTERCEPT_CR3_MASK);
+ control->intercept_cr_read &= ~INTERCEPT_CR3_MASK;
+ control->intercept_cr_write &= ~INTERCEPT_CR3_MASK;
save->g_pat = 0x0007040600070406ULL;
save->cr3 = 0;
save->cr4 = 0;
@@ -982,15 +980,13 @@
}
}
#endif
- if (npt_enabled)
- goto set;
-
vcpu->arch.cr0 = cr0;
- cr0 |= X86_CR0_PG | X86_CR0_WP;
+
+ if (!npt_enabled)
+ cr0 |= X86_CR0_PG | X86_CR0_WP;
if (!vcpu->fpu_active)
cr0 |= X86_CR0_TS;
-set:
/*
* re-enable caching here because the QEMU bios
* does not do it - this results in some delay at
@@ -2386,21 +2382,10 @@
svm_complete_interrupts(svm);
- if (npt_enabled) {
- int mmu_reload = 0;
- if ((kvm_read_cr0_bits(vcpu, X86_CR0_PG) ^ svm->vmcb->save.cr0)
- & X86_CR0_PG) {
- svm_set_cr0(vcpu, svm->vmcb->save.cr0);
- mmu_reload = 1;
- }
+ if (!(svm->vmcb->control.intercept_cr_write & INTERCEPT_CR0_MASK))
vcpu->arch.cr0 = svm->vmcb->save.cr0;
+ if (npt_enabled)
vcpu->arch.cr3 = svm->vmcb->save.cr3;
- if (mmu_reload) {
- kvm_mmu_reset_context(vcpu);
- kvm_mmu_load(vcpu);
- }
- }
-
if (svm->vmcb->control.exit_code == SVM_EXIT_ERR) {
kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;