diff options
| -rw-r--r-- | arch/arm64/kvm/mmu.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 5fe24f30999d..708a635e38bc 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1465,6 +1465,18 @@ static bool kvm_vma_mte_allowed(struct vm_area_struct *vma) return vma->vm_flags & VM_MTE_ALLOWED; } +static bool kvm_vma_is_cacheable(struct vm_area_struct *vma) +{ + switch (FIELD_GET(PTE_ATTRINDX_MASK, pgprot_val(vma->vm_page_prot))) { + case MT_NORMAL_NC: + case MT_DEVICE_nGnRnE: + case MT_DEVICE_nGnRE: + return false; + default: + return true; + } +} + static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, struct kvm_s2_trans *nested, struct kvm_memory_slot *memslot, unsigned long hva, @@ -1472,7 +1484,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, { int ret = 0; bool write_fault, writable, force_pte = false; - bool exec_fault, mte_allowed; + bool exec_fault, mte_allowed, is_vma_cacheable; bool s2_force_noncacheable = false, vfio_allow_any_uc = false; unsigned long mmu_seq; phys_addr_t ipa = fault_ipa; @@ -1617,6 +1629,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, vm_flags = vma->vm_flags; + is_vma_cacheable = kvm_vma_is_cacheable(vma); + /* Don't use the VMA after the unlock -- it may have vanished */ vma = NULL; @@ -1660,6 +1674,15 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, writable = false; } + /* + * Prevent non-cacheable mappings in the stage-2 if a region of memory + * is cacheable in the primary MMU and the kernel lacks a cacheable + * alias. KVM cannot guarantee coherency between the guest/host aliases + * without the ability to perform CMOs. + */ + if (is_vma_cacheable && s2_force_noncacheable) + return -EINVAL; + if (exec_fault && s2_force_noncacheable) return -ENOEXEC; @@ -2219,6 +2242,12 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, ret = -EINVAL; break; } + + /* Cacheable PFNMAP is not allowed */ + if (kvm_vma_is_cacheable(vma)) { + ret = -EINVAL; + break; + } } hva = min(reg_end, vma->vm_end); } while (hva < reg_end); |