squash! KVM: arm64: Prefault entries when splitting a block mapping - Don't prefault entries intersecting with the target range Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 42c8a9d..81ecd2d 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c

@@ -918,24 +918,34 @@ static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level,
 	return 0;
 }
 
-static void stage2_map_prefault_idmap(u64 addr, u32 level, kvm_pte_t *ptep,
-				      kvm_pte_t attr)
+static void stage2_map_prefault_idmap(u64 addr, u64 end, u32 level,
+				      kvm_pte_t *ptep, kvm_pte_t attr)
 {
-	bool cont = kvm_contiguous_pte_alignment(level);
+	u64 addr_align, pte_align = kvm_contiguous_pte_alignment(level);
+	u64 curr = ALIGN_DOWN(addr, kvm_granule_size(level - 1));
 	u64 granule = kvm_granule_size(level);
 	int i;
 
 	if (!kvm_pte_valid(attr))
 		return;
 
-	for (i = 0; i < PTRS_PER_PTE; ++i, ++ptep, addr += granule) {
-		kvm_pte_t pte = kvm_init_valid_leaf_pte(addr, attr, level);
+	addr_align = pte_align / sizeof(kvm_pte_t) * granule;
 
-		if (cont)
+	for (i = 0; i < PTRS_PER_PTE; ++i, ++ptep, curr += granule) {
+		kvm_pte_t pte = kvm_init_valid_leaf_pte(curr, attr, level);
+
+		if (curr >= addr && curr < end)
+			continue;
+
+		if (addr_align &&
+		    (curr < ALIGN_DOWN(addr, addr_align) ||
+		     curr >= round_up(end, addr_align))) {
 			pte |= KVM_PTE_LEAF_ATTR_HI_S2_CONT;
+		}
 
 		WRITE_ONCE(*ptep, pte);
 	}
+
 }
 
 static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
@@ -986,10 +996,8 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
 	kvm_set_table_pte(ptep, childp, mm_ops);
 	mm_ops->get_page(ptep);
 
-	if (pgt->flags & KVM_PGTABLE_S2_IDMAP) {
-		addr = ALIGN_DOWN(addr, kvm_granule_size(level));
-		stage2_map_prefault_idmap(addr, level + 1, childp, pte);
-	}
+	if (pgt->flags & KVM_PGTABLE_S2_IDMAP)
+		stage2_map_prefault_idmap(addr, end, level + 1, childp, pte);
 
 	return 0;
 }