arm/arm64: KVM: Enforce Break-Before-Make on Stage-2 page tables

[firefly-linux-kernel-4.4.55.git] / arch / arm / kvm / mmu.c

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 7dace909d5cf158c9f7771da8ef7c951ee2dea1c..12d727fae0a7592d3d4ca947ea0507d2fb01c63d 100644 (file)
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -218,7 +218,7 @@ static void unmap_ptes(struct kvm *kvm, pmd_t *pmd,
                        kvm_tlb_flush_vmid_ipa(kvm, addr);
 
                        /* No need to invalidate the cache for device mappings */
-                       if (!kvm_is_device_pfn(__phys_to_pfn(addr)))
+                       if (!kvm_is_device_pfn(pte_pfn(old_pte)))
                                kvm_flush_dcache_pte(old_pte);
 
                        put_page(virt_to_page(pte));
@@ -310,7 +310,7 @@ static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd,
 
        pte = pte_offset_kernel(pmd, addr);
        do {
-               if (!pte_none(*pte) && !kvm_is_device_pfn(__phys_to_pfn(addr)))
+               if (!pte_none(*pte) && !kvm_is_device_pfn(pte_pfn(*pte)))
                        kvm_flush_dcache_pte(*pte);
        } while (pte++, addr += PAGE_SIZE, addr != end);
 }
@@ -886,11 +886,14 @@ static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
        VM_BUG_ON(pmd_present(*pmd) && pmd_pfn(*pmd) != pmd_pfn(*new_pmd));
 
        old_pmd = *pmd;
-       kvm_set_pmd(pmd, *new_pmd);
-       if (pmd_present(old_pmd))
+       if (pmd_present(old_pmd)) {
+               pmd_clear(pmd);
                kvm_tlb_flush_vmid_ipa(kvm, addr);
-       else
+       } else {
                get_page(virt_to_page(pmd));
+       }
+
+       kvm_set_pmd(pmd, *new_pmd);
        return 0;
 }
 
@@ -939,12 +942,14 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
 
        /* Create 2nd stage page table mapping - Level 3 */
        old_pte = *pte;
-       kvm_set_pte(pte, *new_pte);
-       if (pte_present(old_pte))
+       if (pte_present(old_pte)) {
+               kvm_set_pte(pte, __pte(0));
                kvm_tlb_flush_vmid_ipa(kvm, addr);
-       else
+       } else {
                get_page(virt_to_page(pte));
+       }
 
+       kvm_set_pte(pte, *new_pte);
        return 0;
 }