From: Wanpeng Li <wanpengli@tencent.com>
Date: Fri, 31 Jul 2020 11:12:21 +0800
Subject: KVM: SVM: Fix disable pause loop exit/pause filtering capability on
 SVM
Git-commit: 830f01b089b12bbe93bd55f2d62837253012a30e
Patch-mainline: v5.8
References: bsc#1176321

'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@tencent.com>
Tested-by: Haiwei Li <lihaiwei@tencent.com>
Fixes: 8566ac8b ("KVM: SVM: Implement pause loop exit logic in SVM")
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1596165141-28874-3-git-send-email-wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 arch/x86/kvm/svm.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -410,6 +410,11 @@ struct enc_region {
 	unsigned long size;
 };
 
+static inline bool svm_pause_in_guest(void)
+{
+	return (!pause_filter_count || !pause_filter_thresh);
+}
+
 static inline bool svm_sev_enabled(void)
 {
 	return max_sev_asid;
@@ -1598,7 +1603,7 @@ static void init_vmcb(struct vcpu_svm *s
 	svm->nested.vmcb = 0;
 	svm->vcpu.arch.hflags = 0;
 
-	if (pause_filter_count) {
+	if (!svm_pause_in_guest()) {
 		control->pause_filter_count = pause_filter_count;
 		if (pause_filter_thresh)
 			control->pause_filter_thresh = pause_filter_thresh;
@@ -4440,7 +4445,7 @@ 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 (!svm_pause_in_guest())
 		grow_ple_window(vcpu);
 
 	kvm_vcpu_on_spin(vcpu, in_kernel);
@@ -6136,7 +6141,7 @@ static void svm_handle_external_intr(str
 
 static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
 {
-	if (pause_filter_thresh)
+	if (!svm_pause_in_guest())
 		shrink_ple_window(vcpu);
 }