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Subject[PATCH 23/54] KVM: x86/mmu: Use MMU's role_regs, not vCPU state, to compute mmu_role
From
Use the provided role_regs to calculate the mmu_role instead of pulling
bits from current vCPU state. For some flows, e.g. nested TDP, the vCPU
state may not be correct (or relevant).

Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/mmu/mmu.c | 92 ++++++++++++++++++++++++------------------
1 file changed, 52 insertions(+), 40 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 84a40488eba7..896e92eac28b 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4542,17 +4542,18 @@ static void paging32E_init_context(struct kvm_vcpu *vcpu,
paging64_init_context_common(vcpu, context, PT32E_ROOT_LEVEL);
}

-static union kvm_mmu_extended_role kvm_calc_mmu_role_ext(struct kvm_vcpu *vcpu)
+static union kvm_mmu_extended_role kvm_calc_mmu_role_ext(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs)
{
union kvm_mmu_extended_role ext = {0};

- ext.cr0_pg = !!is_paging(vcpu);
- ext.cr4_pae = !!is_pae(vcpu);
- ext.cr4_smep = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMEP);
- ext.cr4_smap = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMAP);
- ext.cr4_pse = !!is_pse(vcpu);
- ext.cr4_pke = !!kvm_read_cr4_bits(vcpu, X86_CR4_PKE);
- ext.cr4_la57 = !!kvm_read_cr4_bits(vcpu, X86_CR4_LA57);
+ ext.cr0_pg = ____is_cr0_pg(regs);
+ ext.cr4_pae = ____is_cr4_pae(regs);
+ ext.cr4_smep = ____is_cr4_smep(regs);
+ ext.cr4_smap = ____is_cr4_smap(regs);
+ ext.cr4_pse = ____is_cr4_pse(regs);
+ ext.cr4_pke = ____is_cr4_pke(regs);
+ ext.cr4_la57 = ____is_cr4_la57(regs);

ext.valid = 1;

@@ -4560,20 +4561,21 @@ static union kvm_mmu_extended_role kvm_calc_mmu_role_ext(struct kvm_vcpu *vcpu)
}

static union kvm_mmu_role kvm_calc_mmu_role_common(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs,
bool base_only)
{
union kvm_mmu_role role = {0};

role.base.access = ACC_ALL;
- role.base.nxe = !!is_nx(vcpu);
- role.base.cr0_wp = is_write_protection(vcpu);
+ role.base.nxe = ____is_efer_nx(regs);
+ role.base.cr0_wp = ____is_cr0_wp(regs);
role.base.smm = is_smm(vcpu);
role.base.guest_mode = is_guest_mode(vcpu);

if (base_only)
return role;

- role.ext = kvm_calc_mmu_role_ext(vcpu);
+ role.ext = kvm_calc_mmu_role_ext(vcpu, regs);

return role;
}
@@ -4588,9 +4590,10 @@ static inline int kvm_mmu_get_tdp_level(struct kvm_vcpu *vcpu)
}

static union kvm_mmu_role
-kvm_calc_tdp_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
+kvm_calc_tdp_mmu_root_page_role(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs, bool base_only)
{
- union kvm_mmu_role role = kvm_calc_mmu_role_common(vcpu, base_only);
+ union kvm_mmu_role role = kvm_calc_mmu_role_common(vcpu, regs, base_only);

role.base.ad_disabled = (shadow_accessed_mask == 0);
role.base.level = kvm_mmu_get_tdp_level(vcpu);
@@ -4603,8 +4606,9 @@ kvm_calc_tdp_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
{
struct kvm_mmu *context = &vcpu->arch.root_mmu;
+ struct kvm_mmu_role_regs regs = vcpu_to_role_regs(vcpu);
union kvm_mmu_role new_role =
- kvm_calc_tdp_mmu_root_page_role(vcpu, false);
+ kvm_calc_tdp_mmu_root_page_role(vcpu, &regs, false);

if (new_role.as_u64 == context->mmu_role.as_u64)
return;
@@ -4648,30 +4652,30 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
}

static union kvm_mmu_role
-kvm_calc_shadow_root_page_role_common(struct kvm_vcpu *vcpu, bool base_only)
+kvm_calc_shadow_root_page_role_common(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs, bool base_only)
{
- union kvm_mmu_role role = kvm_calc_mmu_role_common(vcpu, base_only);
+ union kvm_mmu_role role = kvm_calc_mmu_role_common(vcpu, regs, base_only);

- role.base.smep_andnot_wp = role.ext.cr4_smep &&
- !is_write_protection(vcpu);
- role.base.smap_andnot_wp = role.ext.cr4_smap &&
- !is_write_protection(vcpu);
- role.base.gpte_is_8_bytes = !!is_pae(vcpu);
+ role.base.smep_andnot_wp = role.ext.cr4_smep && !____is_cr0_wp(regs);
+ role.base.smap_andnot_wp = role.ext.cr4_smap && !____is_cr0_wp(regs);
+ role.base.gpte_is_8_bytes = ____is_cr4_pae(regs);

return role;
}

static union kvm_mmu_role
-kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
+kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs, bool base_only)
{
union kvm_mmu_role role =
- kvm_calc_shadow_root_page_role_common(vcpu, base_only);
+ kvm_calc_shadow_root_page_role_common(vcpu, regs, base_only);

- role.base.direct = !is_paging(vcpu);
+ role.base.direct = !____is_cr0_pg(regs);

- if (!is_long_mode(vcpu))
+ if (!____is_efer_lma(regs))
role.base.level = PT32E_ROOT_LEVEL;
- else if (is_la57_mode(vcpu))
+ else if (____is_cr4_la57(regs))
role.base.level = PT64_ROOT_5LEVEL;
else
role.base.level = PT64_ROOT_4LEVEL;
@@ -4709,17 +4713,18 @@ static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu,
{
struct kvm_mmu *context = &vcpu->arch.root_mmu;
union kvm_mmu_role new_role =
- kvm_calc_shadow_mmu_root_page_role(vcpu, false);
+ 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);
}

static union kvm_mmu_role
-kvm_calc_shadow_npt_root_page_role(struct kvm_vcpu *vcpu)
+kvm_calc_shadow_npt_root_page_role(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_role_regs *regs)
{
union kvm_mmu_role role =
- kvm_calc_shadow_root_page_role_common(vcpu, false);
+ kvm_calc_shadow_root_page_role_common(vcpu, regs, false);

role.base.direct = false;
role.base.level = kvm_mmu_get_tdp_level(vcpu);
@@ -4736,7 +4741,9 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
.cr4 = cr4,
.efer = efer,
};
- union kvm_mmu_role new_role = kvm_calc_shadow_npt_root_page_role(vcpu);
+ union kvm_mmu_role new_role;
+
+ new_role = kvm_calc_shadow_npt_root_page_role(vcpu, &regs);

__kvm_mmu_new_pgd(vcpu, nested_cr3, new_role.base);

@@ -4821,9 +4828,12 @@ static void init_kvm_softmmu(struct kvm_vcpu *vcpu)
context->inject_page_fault = kvm_inject_page_fault;
}

-static union kvm_mmu_role kvm_calc_nested_mmu_role(struct kvm_vcpu *vcpu)
+static union kvm_mmu_role
+kvm_calc_nested_mmu_role(struct kvm_vcpu *vcpu, struct kvm_mmu_role_regs *regs)
{
- union kvm_mmu_role role = kvm_calc_shadow_root_page_role_common(vcpu, false);
+ union kvm_mmu_role role;
+
+ role = kvm_calc_shadow_root_page_role_common(vcpu, regs, false);

/*
* Nested MMUs are used only for walking L2's gva->gpa, they never have
@@ -4832,12 +4842,12 @@ static union kvm_mmu_role kvm_calc_nested_mmu_role(struct kvm_vcpu *vcpu)
*/
role.base.direct = true;

- if (!is_paging(vcpu))
+ if (!____is_cr0_pg(regs))
role.base.level = 0;
- else if (is_long_mode(vcpu))
- role.base.level = is_la57_mode(vcpu) ? PT64_ROOT_5LEVEL :
- PT64_ROOT_4LEVEL;
- else if (is_pae(vcpu))
+ else if (____is_efer_lma(regs))
+ role.base.level = ____is_cr4_la57(regs) ? PT64_ROOT_5LEVEL :
+ PT64_ROOT_4LEVEL;
+ else if (____is_cr4_pae(regs))
role.base.level = PT32E_ROOT_LEVEL;
else
role.base.level = PT32_ROOT_LEVEL;
@@ -4847,7 +4857,8 @@ static union kvm_mmu_role kvm_calc_nested_mmu_role(struct kvm_vcpu *vcpu)

static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
{
- union kvm_mmu_role new_role = kvm_calc_nested_mmu_role(vcpu);
+ struct kvm_mmu_role_regs regs = vcpu_to_role_regs(vcpu);
+ union kvm_mmu_role new_role = kvm_calc_nested_mmu_role(vcpu, &regs);
struct kvm_mmu *g_context = &vcpu->arch.nested_mmu;

if (new_role.as_u64 == g_context->mmu_role.as_u64)
@@ -4913,12 +4924,13 @@ EXPORT_SYMBOL_GPL(kvm_init_mmu);
static union kvm_mmu_page_role
kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu)
{
+ struct kvm_mmu_role_regs regs = vcpu_to_role_regs(vcpu);
union kvm_mmu_role role;

if (tdp_enabled)
- role = kvm_calc_tdp_mmu_root_page_role(vcpu, true);
+ role = kvm_calc_tdp_mmu_root_page_role(vcpu, &regs, true);
else
- role = kvm_calc_shadow_mmu_root_page_role(vcpu, true);
+ role = kvm_calc_shadow_mmu_root_page_role(vcpu, &regs, true);

return role.base;
}
--
2.32.0.288.g62a8d224e6-goog
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