Commit 888f9f3e authored by Avi Kivity's avatar Avi Kivity Committed by Marcelo Tosatti
Browse files

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: default avatarJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent bff78274

arch/x86/kvm/svm.c

+7 −22
Original line number Diff line number Diff line
@@ -643,10 +643,8 @@ static void init_vmcb(struct vcpu_svm *svm) 
		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 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) 
		}

	}

#endif

	if (npt_enabled)

		goto set;



	vcpu->arch.cr0 = cr0;



	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 @@ static int handle_exit(struct kvm_vcpu *vcpu) 


	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;

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