diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 2aec7ab59aeb..3c843223b4ed 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -58,7 +58,8 @@ xfs_get_extsz_hint(
 		return 0;
 	if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
 		return ip->i_extsize;
-	if (XFS_IS_REALTIME_INODE(ip))
+	if (XFS_IS_REALTIME_INODE(ip) &&
+	    ip->i_mount->m_sb.sb_rextsize > 1)
 		return ip->i_mount->m_sb.sb_rextsize;
 	return 0;
 }
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index bba5a0d87d03..9ce0f6b9df93 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -1001,8 +1001,6 @@ xfs_buffered_write_iomap_begin(
 		return xfs_direct_write_iomap_begin(inode, offset, count,
 				flags, iomap, srcmap);
 
-	ASSERT(!XFS_IS_REALTIME_INODE(ip));
-
 	error = xfs_qm_dqattach(ip);
 	if (error)
 		return error;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 7f0c840f0fd2..ad76704ab133 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -525,7 +525,7 @@ xfs_stat_blksize(
 	 * always return the realtime extent size.
 	 */
 	if (XFS_IS_REALTIME_INODE(ip))
-		return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip));
+		return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip) ? : 1);
 
 	/*
 	 * Allow large block sizes to be reported to userspace programs if the
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index 86f928d30fed..b476a876478d 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -1341,6 +1341,8 @@ xfs_bmap_rtalloc(
 	int			error;
 
 	align = xfs_get_extsz_hint(ap->ip);
+	if (!align)
+		align = 1;
 retry:
 	error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
 					align, 1, ap->eof, 0,