linux-kernel - [PATCH 37/54] KVM: x86/mmu: Use MMU's role to get EFER.NX during MMU configuration

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Message-Id: <20210622175739.3610207-38-seanjc@google.com>
Date:   Tue, 22 Jun 2021 10:57:22 -0700
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Yu Zhang <yu.c.zhang@...ux.intel.com>,
        Maxim Levitsky <mlevitsk@...hat.com>
Subject: [PATCH 37/54] KVM: x86/mmu: Use MMU's role to get EFER.NX during MMU configuration

Get the MMU's effective EFER.NX from its role instead of using the
one-off, dedicated flag.  This will allow dropping said flag in a
future commit.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/mmu/mmu.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 30cbc6cdb0db..eb6386bcc2ef 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4212,7 +4212,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
 {
 	__reset_rsvds_bits_mask(&context->guest_rsvd_check,
 				vcpu->arch.reserved_gpa_bits,
-				context->root_level, context->nx,
+				context->root_level, is_efer_nx(context),
 				guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES),
 				is_cr4_pse(context),
 				guest_cpuid_is_amd_or_hygon(vcpu));
@@ -4278,7 +4278,7 @@ static void reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu,
 	 * NX can be used by any non-nested shadow MMU to avoid having to reset
 	 * MMU contexts.  Note, KVM forces EFER.NX=1 when TDP is disabled.
 	 */
-	bool uses_nx = context->nx || !tdp_enabled;
+	bool uses_nx = is_efer_nx(context) || !tdp_enabled;
 
 	/* @amd adds a check on bit of SPTEs, which KVM shouldn't use anyways. */
 	bool is_amd = true;
@@ -4375,6 +4375,7 @@ static void update_permission_bitmask(struct kvm_mmu *mmu, bool ept)
 	bool cr4_smep = is_cr4_smep(mmu);
 	bool cr4_smap = is_cr4_smap(mmu);
 	bool cr0_wp = is_cr0_wp(mmu);
+	bool efer_nx = is_efer_nx(mmu);
 
 	for (byte = 0; byte < ARRAY_SIZE(mmu->permissions); ++byte) {
 		unsigned pfec = byte << 1;
@@ -4400,7 +4401,7 @@ static void update_permission_bitmask(struct kvm_mmu *mmu, bool ept)
 			u8 kf = (pfec & PFERR_USER_MASK) ? 0 : u;
 
 			/* Not really needed: !nx will cause pte.nx to fault */
-			if (!mmu->nx)
+			if (!efer_nx)
 				ff = 0;
 
 			/* Allow supervisor writes if !cr0.wp */
-- 
2.32.0.288.g62a8d224e6-goog