linux-kernel - [PATCH 5.7 119/120] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM

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Date:   Mon,  3 Aug 2020 14:19:37 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Haiwei Li <lihaiwei@...cent.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Subject: [PATCH 5.7 119/120] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM

From: Wanpeng Li <wanpengli@...cent.com>

commit 830f01b089b12bbe93bd55f2d62837253012a30e upstream.

'Commit 8566ac8b8e7c ("KVM: SVM: Implement pause loop exit logic in SVM")'
drops disable pause loop exit/pause filtering capability completely, I
guess it is a merge fault by Radim since disable vmexits capabilities and
pause loop exit for SVM patchsets are merged at the same time. This patch
reintroduces the disable pause loop exit/pause filtering capability support.

Reported-by: Haiwei Li <lihaiwei@...cent.com>
Tested-by: Haiwei Li <lihaiwei@...cent.com>
Fixes: 8566ac8b ("KVM: SVM: Implement pause loop exit logic in SVM")
Signed-off-by: Wanpeng Li <wanpengli@...cent.com>
Message-Id: <1596165141-28874-3-git-send-email-wanpengli@...cent.com>
Cc: stable@...r.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 arch/x86/kvm/svm/svm.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1105,7 +1105,7 @@ static void init_vmcb(struct vcpu_svm *s
 	svm->nested.vmcb = 0;
 	svm->vcpu.arch.hflags = 0;
 
-	if (pause_filter_count) {
+	if (!kvm_pause_in_guest(svm->vcpu.kvm)) {
 		control->pause_filter_count = pause_filter_count;
 		if (pause_filter_thresh)
 			control->pause_filter_thresh = pause_filter_thresh;
@@ -2682,7 +2682,7 @@ static int pause_interception(struct vcp
 	struct kvm_vcpu *vcpu = &svm->vcpu;
 	bool in_kernel = (svm_get_cpl(vcpu) == 0);
 
-	if (pause_filter_thresh)
+	if (!kvm_pause_in_guest(vcpu->kvm))
 		grow_ple_window(vcpu);
 
 	kvm_vcpu_on_spin(vcpu, in_kernel);
@@ -3727,7 +3727,7 @@ static void svm_handle_exit_irqoff(struc
 
 static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
 {
-	if (pause_filter_thresh)
+	if (!kvm_pause_in_guest(vcpu->kvm))
 		shrink_ple_window(vcpu);
 }
 
@@ -3892,6 +3892,9 @@ static void svm_vm_destroy(struct kvm *k
 
 static int svm_vm_init(struct kvm *kvm)
 {
+	if (!pause_filter_count || !pause_filter_thresh)
+		kvm->arch.pause_in_guest = true;
+
 	if (avic) {
 		int ret = avic_vm_init(kvm);
 		if (ret)