To run xfstest on overlayfs, configure the variables of TEST and SCRATCH partitions to be used as the "base fs" and run './check -overlay'. For example, the following config file can be used to run tests on xfs test/scratch partitions: TEST_DEV=/dev/sda5 TEST_DIR=/mnt/test SCRATCH_DEV=/dev/sda6 SCRATCH_MNT=/mnt/scratch FSTYP=xfs Using the same config file, but executing './check -overlay' will use the same partitions as base fs for overlayfs directories and set TEST_DIR/SCRATCH_MNT values to overlay mount points, i.e.: /mnt/test/ovl-mnt and /mnt/scratch/ovl-mnt, for the context of individual tests. './check -overlay' does not support mkfs and fsck on the base fs, so the base fs should be pre-formatted before starting the -overlay run. An easy way to accomplish this is by running './check ' once, before running './check -overlay'. Because of the lack of mkfs support, multi-section config files are only partly supported with './check -overlay'. Only multi-section files that do not change FSTYP and MKFS_OPTIONS can be safely used with -overlay. For example, the following multi-section config file can be used to run overlay tests on the same base fs, but with different mount options: [xfs] TEST_DEV=/dev/sda5 TEST_DIR=/mnt/test SCRATCH_DEV=/dev/sda6 SCRATCH_MNT=/mnt/scratch FSTYP=xfs [xfs_pquota] MOUNT_OPTIONS="-o pquota" TEST_FS_MOUNT_OPTS="-o noatime" OVERLAY_MOUNT_OPTIONS="-o redirect_dir=off" In the example above, MOUNT_OPTIONS will be used to mount the base scratch fs, TEST_FS_MOUNT_OPTS will be used to mount the base test fs and OVERLAY_MOUNT_OPTIONS will be used to mount both test and scratch overlays.