Index: sys/fs/cd9660/cd9660_vfsops.c
===================================================================
RCS file: /cvsroot/src/sys/fs/cd9660/cd9660_vfsops.c,v
retrieving revision 1.105
diff -p -u -r1.105 cd9660_vfsops.c
--- sys/fs/cd9660/cd9660_vfsops.c	16 Feb 2025 18:38:58 -0000	1.105
+++ sys/fs/cd9660/cd9660_vfsops.c	22 Nov 2025 08:13:38 -0000
@@ -419,7 +419,8 @@ iso_mountfs(struct vnode *devvp, struct 
 	error = VOP_IOCTL(devvp, DIOCGDINFO, &label, FREAD, FSCRED);
 	if (!error) {
 		/* XXX more sanity checks? */
-		sess = label.d_partitions[DISKPART(dev)].p_cdsession;
+		if (label.d_partitions[DISKPART(dev)].p_fstype == FS_ISO9660)
+			sess = label.d_partitions[DISKPART(dev)].p_cdsession;
 	} else {
 		/* fallback to old method */
 		error = VOP_IOCTL(devvp, CDIOREADMSADDR, &sess, 0, FSCRED);