diff options
| author | Sean Christopherson <seanjc@google.com> | 2022-10-19 16:56:16 +0000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-11-09 12:31:33 -0500 |
| commit | 5e3edd7e8b7e8004c9bb8310fd669a9ca81de207 (patch) | |
| tree | 207a5d723daf2bf658d1204dcd832f70794e8caa /arch/x86/kvm/mmu/mmu.c | |
| parent | d25ceb9264364dca0683748b301340097fdab6c7 (diff) | |
KVM: x86/mmu: Add helper to convert SPTE value to its shadow page
Add a helper to convert a SPTE to its shadow page to deduplicate a
variety of flows and hopefully avoid future bugs, e.g. if KVM attempts to
get the shadow page for a SPTE without dropping high bits.
Opportunistically add a comment in mmu_free_root_page() documenting why
it treats the root HPA as a SPTE.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20221019165618.927057-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/mmu/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index e384b78e099c..5f9b57c6e506 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1819,7 +1819,7 @@ static int __mmu_unsync_walk(struct kvm_mmu_page *sp, continue; } - child = to_shadow_page(ent & SPTE_BASE_ADDR_MASK); + child = spte_to_child_sp(ent); if (child->unsync_children) { if (mmu_pages_add(pvec, child, i)) @@ -2378,7 +2378,7 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, * so we should update the spte at this point to get * a new sp with the correct access. */ - child = to_shadow_page(*sptep & SPTE_BASE_ADDR_MASK); + child = spte_to_child_sp(*sptep); if (child->role.access == direct_access) return; @@ -2399,7 +2399,7 @@ static int mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp, if (is_last_spte(pte, sp->role.level)) { drop_spte(kvm, spte); } else { - child = to_shadow_page(pte & SPTE_BASE_ADDR_MASK); + child = spte_to_child_sp(pte); drop_parent_pte(child, spte); /* @@ -2838,7 +2838,7 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, struct kvm_mmu_page *child; u64 pte = *sptep; - child = to_shadow_page(pte & SPTE_BASE_ADDR_MASK); + child = spte_to_child_sp(pte); drop_parent_pte(child, sptep); flush = true; } else if (pfn != spte_to_pfn(*sptep)) { @@ -3455,7 +3455,11 @@ static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa, if (!VALID_PAGE(*root_hpa)) return; - sp = to_shadow_page(*root_hpa & SPTE_BASE_ADDR_MASK); + /* + * The "root" may be a special root, e.g. a PAE entry, treat it as a + * SPTE to ensure any non-PA bits are dropped. + */ + sp = spte_to_child_sp(*root_hpa); if (WARN_ON(!sp)) return; @@ -3940,8 +3944,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) hpa_t root = vcpu->arch.mmu->pae_root[i]; if (IS_VALID_PAE_ROOT(root)) { - root &= SPTE_BASE_ADDR_MASK; - sp = to_shadow_page(root); + sp = spte_to_child_sp(root); mmu_sync_children(vcpu, sp, true); } } |