diff --git a/fs/xfs/scrub/rgsuper.c b/fs/xfs/scrub/rgsuper.c
index 2bd2c0351b35..6e2abe5dc27c 100644
--- a/fs/xfs/scrub/rgsuper.c
+++ b/fs/xfs/scrub/rgsuper.c
@@ -36,8 +36,10 @@ xchk_rgsuperblock_xref(
 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 		return;
 
-	xchk_xref_is_used_rt_space(sc, xfs_rgbno_to_rtb(sc->sr.rtg, 0), 1);
-	xchk_xref_is_only_rt_owned_by(sc, 0, 1, &XFS_RMAP_OINFO_FS);
+	xchk_xref_is_used_rt_space(sc, xfs_rgbno_to_rtb(sc->sr.rtg, 0),
+			sc->mp->m_sb.sb_rextsize);
+	xchk_xref_is_only_rt_owned_by(sc, 0, sc->mp->m_sb.sb_rextsize,
+			&XFS_RMAP_OINFO_FS);
 }
 
 int