diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_radix.c | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index 2a2fad9a1c13..3cb0c9843d01 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -353,7 +353,13 @@ static struct kmem_cache *kvm_pmd_cache; static pte_t *kvmppc_pte_alloc(void) { - return kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); + pte_t *pte; + + pte = kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); + /* pmd_populate() will only reference _pa(pte). */ + kmemleak_ignore(pte); + + return pte; } static void kvmppc_pte_free(pte_t *ptep) @@ -363,7 +369,13 @@ static void kvmppc_pte_free(pte_t *ptep) static pmd_t *kvmppc_pmd_alloc(void) { - return kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL); + pmd_t *pmd; + + pmd = kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL); + /* pud_populate() will only reference _pa(pmd). */ + kmemleak_ignore(pmd); + + return pmd; } static void kvmppc_pmd_free(pmd_t *pmdp) @@ -417,9 +429,13 @@ void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa, * Callers are responsible for flushing the PWC. * * When page tables are being unmapped/freed as part of page fault path - * (full == false), ptes are not expected. There is code to unmap them - * and emit a warning if encountered, but there may already be data - * corruption due to the unexpected mappings. + * (full == false), valid ptes are generally not expected; however, there + * is one situation where they arise, which is when dirty page logging is + * turned off for a memslot while the VM is running. The new memslot + * becomes visible to page faults before the memslot commit function + * gets to flush the memslot, which can lead to a 2MB page mapping being + * installed for a guest physical address where there are already 64kB + * (or 4kB) mappings (of sub-pages of the same 2MB page). */ static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full, unsigned int lpid) @@ -433,7 +449,6 @@ static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full, for (it = 0; it < PTRS_PER_PTE; ++it, ++p) { if (pte_val(*p) == 0) continue; - WARN_ON_ONCE(1); kvmppc_unmap_pte(kvm, p, pte_pfn(*p) << PAGE_SHIFT, PAGE_SHIFT, NULL, lpid); @@ -891,7 +906,7 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, return ret; } -int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, +int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu, unsigned long ea, unsigned long dsisr) { struct kvm *kvm = vcpu->kvm; @@ -937,7 +952,7 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, kvmppc_core_queue_data_storage(vcpu, ea, dsisr); return RESUME_GUEST; } - return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, writing); + return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); } if (memslot->flags & KVM_MEM_READONLY) { @@ -1142,6 +1157,11 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm, kvm->arch.lpid); gpa += PAGE_SIZE; } + /* + * Increase the mmu notifier sequence number to prevent any page + * fault that read the memslot earlier from writing a PTE. + */ + kvm->mmu_notifier_seq++; spin_unlock(&kvm->mmu_lock); } |