Merge: KVM: SVM: Fix a regression preventing Windows guests from booting

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-10/-/merge_requests/125

JIRA: https://issues.redhat.com/browse/RHEL-71416

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>

Approved-by: Paolo Bonzini <bonzini@gnu.org>
Approved-by: Maxim Levitsky <mlevitsk@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Jan Stancek <jstancek@redhat.com>

Author: jstancek

arch/x86/kvm/svm/svm.c

@@ -3199,15 +3199,6 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
 		if (data & ~supported_de_cfg)
 			return 1;
 
-		/*
-		 * Don't let the guest change the host-programmed value.  The
-		 * MSR is very model specific, i.e. contains multiple bits that
-		 * are completely unknown to KVM, and the one bit known to KVM
-		 * is simply a reflection of hardware capabilities.
-		 */
-		if (!msr->host_initiated && data != svm->msr_decfg)
-			return 1;
-
 		svm->msr_decfg = data;
 		break;
 	}