Commit 18db1b17 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86/mmu: Always set new mmu_role immediately after checking old role 



Refactor shadow MMU initialization to immediately set its new mmu_role
after verifying it differs from the old role, and so that all flavors
of MMU initialization share the same check-and-set pattern.  Immediately
setting the role will allow future commits to use mmu_role to configure
the MMU without consuming stale state.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20210622175739.3610207-29-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 84c679f5

arch/x86/kvm/mmu/mmu.c

+9 −6
Original line number Diff line number Diff line
@@ -4714,6 +4714,11 @@ static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *conte 
				    struct kvm_mmu_role_regs *regs,

				    union kvm_mmu_role new_role)

{

	if (new_role.as_u64 == context->mmu_role.as_u64)

		return;



	context->mmu_role.as_u64 = new_role.as_u64;



	if (!____is_cr0_pg(regs))

		nonpaging_init_context(vcpu, context);

	else if (____is_efer_lma(regs))
@@ -4731,7 +4736,6 @@ static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *conte 
	}

	context->shadow_root_level = new_role.base.level;



	context->mmu_role.as_u64 = new_role.as_u64;

	reset_shadow_zero_bits_mask(vcpu, context);

}
@@ -4742,7 +4746,6 @@ static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, 
	union kvm_mmu_role new_role =

		kvm_calc_shadow_mmu_root_page_role(vcpu, regs, false);



	if (new_role.as_u64 != context->mmu_role.as_u64)

	shadow_mmu_init_context(vcpu, context, regs, new_role);

}
@@ -4774,7 +4777,6 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0, 


	__kvm_mmu_new_pgd(vcpu, nested_cr3, new_role.base);



	if (new_role.as_u64 != context->mmu_role.as_u64)

	shadow_mmu_init_context(vcpu, context, &regs, new_role);



	/*
@@ -4823,6 +4825,8 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, 
	if (new_role.as_u64 == context->mmu_role.as_u64)

		return;



	context->mmu_role.as_u64 = new_role.as_u64;



	context->shadow_root_level = level;



	context->nx = true;
@@ -4833,7 +4837,6 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, 
	context->invlpg = ept_invlpg;

	context->root_level = level;

	context->direct_map = false;

	context->mmu_role.as_u64 = new_role.as_u64;



	update_permission_bitmask(vcpu, context, true);

	update_pkru_bitmask(vcpu, context, true);