Commits
Darrick J. Wong committed 813d32f9133
ext4: check s_chksum_driver when looking for bg csum presence Convert the ext4_has_group_desc_csum predicate to look for a checksum driver instead of the metadata_csum flag and change the bg checksum calculation function to look for GDT_CSUM before taking the crc16 path. Without this patch, if we mount with ^uninit_bg,^metadata_csum and later metadata_csum gets turned on by accident, the block group checksum functions will incorrectly assume that checksumming is enabled (metadata_csum) but that crc16 should be used (!s_chksum_driver). This is totally wrong, so fix the predicate and the checksum formula selection. (Granted, if the metadata_csum feature bit gets enabled on a live FS then something underhanded is going on, but we could at least avoid writing garbage into the on-disk fields.) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Cc: stable@vger.kernel.org