linux-kernel - [PATCH 41/54] KVM: x86/mmu: Consolidate reset_rsvds_bits

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Date:   Tue, 22 Jun 2021 10:57:26 -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 41/54] KVM: x86/mmu: Consolidate reset_rsvds_bits_mask() calls

Move calls to reset_rsvds_bits_mask() out of the various mode statements
and under a more generic !CR0.PG check.  This will allow for additional
code consolidation in the future.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/mmu/mmu.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 30557b3e5c37..52311c2efd5d 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4637,18 +4637,18 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
 	} else if (is_long_mode(vcpu)) {
 		context->root_level = ____is_cr4_la57(&regs) ?
 				PT64_ROOT_5LEVEL : PT64_ROOT_4LEVEL;
-		reset_rsvds_bits_mask(vcpu, context);
 		context->gva_to_gpa = paging64_gva_to_gpa;
 	} else if (is_pae(vcpu)) {
 		context->root_level = PT32E_ROOT_LEVEL;
-		reset_rsvds_bits_mask(vcpu, context);
 		context->gva_to_gpa = paging64_gva_to_gpa;
 	} else {
 		context->root_level = PT32_ROOT_LEVEL;
-		reset_rsvds_bits_mask(vcpu, context);
 		context->gva_to_gpa = paging32_gva_to_gpa;
 	}
 
+	if (is_cr0_pg(context))
+		reset_rsvds_bits_mask(vcpu, context);
+
 	update_permission_bitmask(context, false);
 	update_pkru_bitmask(context);
 	update_last_nonleaf_level(context);
@@ -4890,18 +4890,17 @@ static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
 	 * nested page tables as the second level of translation. Basically
 	 * the gva_to_gpa functions between mmu and nested_mmu are swapped.
 	 */
-	if (!is_paging(vcpu)) {
+	if (!is_paging(vcpu))
 		g_context->gva_to_gpa = nonpaging_gva_to_gpa_nested;
-	} else if (is_long_mode(vcpu)) {
-		reset_rsvds_bits_mask(vcpu, g_context);
+	else if (is_long_mode(vcpu))
 		g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
-	} else if (is_pae(vcpu)) {
-		reset_rsvds_bits_mask(vcpu, g_context);
+	else if (is_pae(vcpu))
 		g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
-	} else {
-		reset_rsvds_bits_mask(vcpu, g_context);
+	else
 		g_context->gva_to_gpa = paging32_gva_to_gpa_nested;
-	}
+
+	if (is_cr0_pg(g_context))
+		reset_rsvds_bits_mask(vcpu, g_context);
 
 	update_permission_bitmask(g_context, false);
 	update_pkru_bitmask(g_context);
-- 
2.32.0.288.g62a8d224e6-goog