diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index c1e6a5bbeeaf..58110c968667 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -2776,20 +2776,14 @@ struct btrfs_data_container *init_data_container(u32 total_bytes)
 	size_t alloc_bytes;
 
 	alloc_bytes = max_t(size_t, total_bytes, sizeof(*data));
-	data = kvmalloc(alloc_bytes, GFP_KERNEL);
+	data = kvzalloc(alloc_bytes, GFP_KERNEL);
 	if (!data)
 		return ERR_PTR(-ENOMEM);
 
-	if (total_bytes >= sizeof(*data)) {
+	if (total_bytes >= sizeof(*data))
 		data->bytes_left = total_bytes - sizeof(*data);
-		data->bytes_missing = 0;
-	} else {
+	else
 		data->bytes_missing = sizeof(*data) - total_bytes;
-		data->bytes_left = 0;
-	}
-
-	data->elem_cnt = 0;
-	data->elem_missed = 0;
 
 	return data;
 }
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 445f7716f1e2..24a048210b15 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -817,7 +817,7 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 					split->block_len = em->block_len;
 					split->orig_start = em->orig_start;
 				} else {
-					const u64 diff = start + len - em->start;
+					const u64 diff = end - em->start;
 
 					split->block_len = split->len;
 					split->block_start += diff;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c65fe5de4022..7fed887e700c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1145,13 +1145,13 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 				   0, *alloc_hint, &ins, 1, 1);
 	if (ret) {
 		/*
-		 * Here we used to try again by going back to non-compressed
-		 * path for ENOSPC.  But we can't reserve space even for
-		 * compressed size, how could it work for uncompressed size
-		 * which requires larger size?  So here we directly go error
-		 * path.
+		 * We can't reserve contiguous space for the compressed size.
+		 * Unlikely, but it's possible that we could have enough
+		 * non-contiguous space for the uncompressed size instead.  So
+		 * fall back to uncompressed.
 		 */
-		goto out_free;
+		submit_uncompressed_range(inode, async_extent, locked_page);
+		goto done;
 	}
 
 	/* Here we're doing allocation and writeback of the compressed pages */
@@ -1203,7 +1203,6 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 out_free_reserve:
 	btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 	btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
-out_free:
 	mapping_set_error(inode->vfs_inode.i_mapping, -EIO);
 	extent_clear_unlock_delalloc(inode, start, end,
 				     NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
diff --git a/fs/btrfs/messages.c b/fs/btrfs/messages.c
index c96dd66fd0f7..210d9c82e2ae 100644
--- a/fs/btrfs/messages.c
+++ b/fs/btrfs/messages.c
@@ -7,7 +7,7 @@
 
 #ifdef CONFIG_PRINTK
 
-#define STATE_STRING_PREFACE	": state "
+#define STATE_STRING_PREFACE	" state "
 #define STATE_STRING_BUF_LEN	(sizeof(STATE_STRING_PREFACE) + BTRFS_FS_STATE_COUNT + 1)
 
 /*
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index fa25004ab04e..4b22cfe9a98c 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1012,6 +1012,7 @@ static void scrub_stripe_read_repair_worker(struct work_struct *work)
 	struct btrfs_fs_info *fs_info = sctx->fs_info;
 	int num_copies = btrfs_num_copies(fs_info, stripe->bg->start,
 					  stripe->bg->length);
+	unsigned long repaired;
 	int mirror;
 	int i;
 
@@ -1078,16 +1079,15 @@ static void scrub_stripe_read_repair_worker(struct work_struct *work)
 	 * Submit the repaired sectors.  For zoned case, we cannot do repair
 	 * in-place, but queue the bg to be relocated.
 	 */
-	if (btrfs_is_zoned(fs_info)) {
-		if (!bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors))
+	bitmap_andnot(&repaired, &stripe->init_error_bitmap, &stripe->error_bitmap,
+		      stripe->nr_sectors);
+	if (!sctx->readonly && !bitmap_empty(&repaired, stripe->nr_sectors)) {
+		if (btrfs_is_zoned(fs_info)) {
 			btrfs_repair_one_zone(fs_info, sctx->stripes[0].bg->start);
-	} else if (!sctx->readonly) {
-		unsigned long repaired;
-
-		bitmap_andnot(&repaired, &stripe->init_error_bitmap,
-			      &stripe->error_bitmap, stripe->nr_sectors);
-		scrub_write_sectors(sctx, stripe, repaired, false);
-		wait_scrub_stripe_io(stripe);
+		} else {
+			scrub_write_sectors(sctx, stripe, repaired, false);
+			wait_scrub_stripe_io(stripe);
+		}
 	}
 
 	scrub_stripe_report_errors(sctx, stripe);
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 253cce7ffecf..47b5d301038e 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -847,6 +847,11 @@ static int test_case_7(struct btrfs_fs_info *fs_info)
 		goto out;
 	}
 
+	if (em->block_start != SZ_32K + SZ_4K) {
+		test_err("em->block_start is %llu, expected 36K", em->block_start);
+		goto out;
+	}
+
 	free_extent_map(em);
 
 	read_lock(&em_tree->lock);