linux-kernel - [PATCH 14/54] KVM: x86: Fix sizes used to pass around CR0, CR4, and EFER

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Message-Id: <20210622175739.3610207-15-seanjc@google.com>
Date:   Tue, 22 Jun 2021 10:56:59 -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 14/54] KVM: x86: Fix sizes used to pass around CR0, CR4, and EFER

When configuring KVM's MMU, pass CR0 and CR4 as unsigned longs, and EFER
as a u64 in various flows (mostly MMU).  Passing the params as u32s is
functionally ok since all of the affected registers reserve bits 63:32 to
zero (enforced by KVM), but it's technically wrong.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/mmu.h        |  4 ++--
 arch/x86/kvm/mmu/mmu.c    | 11 ++++++-----
 arch/x86/kvm/svm/nested.c |  2 +-
 arch/x86/kvm/x86.c        |  2 +-
 4 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index bc11402df83b..47131b92b990 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -66,8 +66,8 @@ void
 reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context);
 
 void kvm_init_mmu(struct kvm_vcpu *vcpu);
-void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer,
-			     gpa_t nested_cr3);
+void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
+			     unsigned long cr4, u64 efer, gpa_t nested_cr3);
 void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly,
 			     bool accessed_dirty, gpa_t new_eptp);
 bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0171c245ecc7..96c16a6e0044 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4659,8 +4659,8 @@ kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
 }
 
 static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *context,
-				    u32 cr0, u32 cr4, u32 efer,
-				    union kvm_mmu_role new_role)
+				    unsigned long cr0, unsigned long cr4,
+				    u64 efer, union kvm_mmu_role new_role)
 {
 	if (!(cr0 & X86_CR0_PG))
 		nonpaging_init_context(vcpu, context);
@@ -4675,7 +4675,8 @@ static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *conte
 	reset_shadow_zero_bits_mask(vcpu, context);
 }
 
-static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer)
+static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
+				unsigned long cr4, u64 efer)
 {
 	struct kvm_mmu *context = &vcpu->arch.root_mmu;
 	union kvm_mmu_role new_role =
@@ -4697,8 +4698,8 @@ kvm_calc_shadow_npt_root_page_role(struct kvm_vcpu *vcpu)
 	return role;
 }
 
-void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer,
-			     gpa_t nested_cr3)
+void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
+			     unsigned long cr4, u64 efer, gpa_t nested_cr3)
 {
 	struct kvm_mmu *context = &vcpu->arch.guest_mmu;
 	union kvm_mmu_role new_role = kvm_calc_shadow_npt_root_page_role(vcpu);
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index dca20f949b63..9f0e7ed672b2 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1244,8 +1244,8 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
 		&user_kvm_nested_state->data.svm[0];
 	struct vmcb_control_area *ctl;
 	struct vmcb_save_area *save;
+	unsigned long cr0;
 	int ret;
-	u32 cr0;
 
 	BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
 		     KVM_STATE_NESTED_SVM_VMCB_SIZE);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 92b4a9305651..2d3b9f10b14a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9076,8 +9076,8 @@ static void enter_smm(struct kvm_vcpu *vcpu)
 {
 	struct kvm_segment cs, ds;
 	struct desc_ptr dt;
+	unsigned long cr0;
 	char buf[512];
-	u32 cr0;
 
 	memset(buf, 0, 512);
 #ifdef CONFIG_X86_64
-- 
2.32.0.288.g62a8d224e6-goog