diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 20f5d301d32dd..a319362217037 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -167,10 +167,10 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
 	if (bip->bip_vcnt > 0) {
 		struct bio_vec *bv = &bip->bip_vec[bip->bip_vcnt - 1];
 
-		if (!zone_device_pages_have_same_pgmap(bv->bv_page, page))
+		if (!zone_device_pages_compatible(bv->bv_page, page))
 			return 0;
-
-		if (bvec_try_merge_hw_page(q, bv, page, len, offset)) {
+		if (zone_device_pages_have_same_pgmap(bv->bv_page, page) &&
+		    bvec_try_merge_hw_page(q, bv, page, len, offset)) {
 			bip->bip_iter.bi_size += len;
 			return len;
 		}
diff --git a/block/bio.c b/block/bio.c
index d80d5d26804e3..3acd216bbc2ee 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1070,10 +1070,10 @@ int bio_add_page(struct bio *bio, struct page *page,
 	if (bio->bi_vcnt > 0) {
 		struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
 
-		if (!zone_device_pages_have_same_pgmap(bv->bv_page, page))
+		if (!zone_device_pages_compatible(bv->bv_page, page))
 			return 0;
-
-		if (bvec_try_merge_page(bv, page, len, offset)) {
+		if (zone_device_pages_have_same_pgmap(bv->bv_page, page) &&
+		    bvec_try_merge_page(bv, page, len, offset)) {
 			bio->bi_iter.bi_size += len;
 			return len;
 		}
diff --git a/block/blk.h b/block/blk.h
index f6053e9dd2aac..a7abf3be34ef8 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -132,6 +132,8 @@ static inline bool biovec_phys_mergeable(struct request_queue *q,
 
 	if (addr1 + vec1->bv_len != addr2)
 		return false;
+	if (!zone_device_pages_have_same_pgmap(vec1->bv_page, vec2->bv_page))
+		return false;
 	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
 		return false;
 	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
@@ -139,6 +141,25 @@ static inline bool biovec_phys_mergeable(struct request_queue *q,
 	return true;
 }
 
+/*
+ * Check if two pages from potentially different zone device pgmaps can
+ * coexist as separate bvec entries in the same bio.
+ *
+ * The block DMA iterator (blk_dma_map_iter_start) caches the P2PDMA mapping
+ * state from the first segment and applies it to all subsequent segments, so
+ * P2PDMA pages from different pgmaps must not be mixed in the same bio.
+ *
+ * Other zone device types (FS_DAX, GENERIC) use the same dma_map_phys() path
+ * as normal RAM.  PRIVATE and COHERENT pages never appear in bios.
+ */
+static inline bool zone_device_pages_compatible(const struct page *a,
+						const struct page *b)
+{
+	if (is_pci_p2pdma_page(a) || is_pci_p2pdma_page(b))
+		return zone_device_pages_have_same_pgmap(a, b);
+	return true;
+}
+
 static inline bool __bvec_gap_to_prev(const struct queue_limits *lim,
 		struct bio_vec *bprv, unsigned int offset)
 {