diff options
| -rw-r--r-- | arch/arm64/kvm/hyp/pgtable.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 1ee1168ac32d..2689fcb7901d 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -362,6 +362,21 @@ static int hyp_set_prot_attr(enum kvm_pgtable_prot prot, kvm_pte_t *ptep) return 0; } +static bool hyp_pte_needs_update(kvm_pte_t old, kvm_pte_t new) +{ + /* + * Tolerate KVM recreating the exact same mapping, or changing software + * bits if the existing mapping was valid. + */ + if (old == new) + return false; + + if (!kvm_pte_valid(old)) + return true; + + return !WARN_ON((old ^ new) & ~KVM_PTE_LEAF_ATTR_HI_SW); +} + static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct hyp_map_data *data) { @@ -371,9 +386,8 @@ static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, if (!kvm_block_mapping_supported(addr, end, phys, level)) return false; - /* Tolerate KVM recreating the exact same mapping */ new = kvm_init_valid_leaf_pte(phys, data->attr, level); - if (old != new && !WARN_ON(kvm_pte_valid(old))) + if (hyp_pte_needs_update(old, new)) smp_store_release(ptep, new); data->phys += granule; |