linux-kernel - [PATCH 22/28] KVM: SVM: Drop explicit check on MSRPM offset when emulating SEV-ES accesses

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Message-ID: <20250529234013.3826933-23-seanjc@google.com>
Date: Thu, 29 May 2025 16:40:07 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Borislav Petkov <bp@...en8.de>, Xin Li <xin@...or.com>, Chao Gao <chao.gao@...el.com>, 
	Dapeng Mi <dapeng1.mi@...ux.intel.com>
Subject: [PATCH 22/28] KVM: SVM: Drop explicit check on MSRPM offset when
 emulating SEV-ES accesses

Now that msr_write_intercepted() defaults to true, i.e. accurately reflects
hardware behavior for out-of-range MSRs, and doesn't WARN (or BUG) on an
out-of-range MSR, drop sev_es_prevent_msr_access()'s svm_msrpm_offset()
check that guarded against calling msr_write_intercepted() with a "bad"
index.

Opportunistically clean up the helper's formatting.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/svm.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 2ebac30a337a..9d01776d82d4 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2771,12 +2771,11 @@ static int svm_get_feature_msr(u32 msr, u64 *data)
 	return 0;
 }
 
-static bool
-sev_es_prevent_msr_access(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+static bool sev_es_prevent_msr_access(struct kvm_vcpu *vcpu,
+				      struct msr_data *msr_info)
 {
 	return sev_es_guest(vcpu->kvm) &&
 	       vcpu->arch.guest_state_protected &&
-	       svm_msrpm_offset(msr_info->index) != MSR_INVALID &&
 	       !msr_write_intercepted(vcpu, msr_info->index);
 }
 
-- 
2.49.0.1204.g71687c7c1d-goog