If segs_per_sec is over 1 like under SMR, previously f2fs issues discard commands redundantly on the same section, since we didn't move end position for the previous discard command. E.g., start end | | prefree_bitmap = [01111100111100] And, after issue discard for this section, end start | | prefree_bitmap = [01111100111100] Select this section again by searching from (end + 1), start end | | prefree_bitmap = [01111100111100] Fixes: 36abef4e796d38 ("f2fs: introduce mode=lfs mount option") Cc: <stable@xxxxxxxxxxxxxxx> Cc: Damien Le Moal <damien.lemoal@xxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> --- fs/f2fs/segment.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 9006d8ed6f52..4bd7a8b19332 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1036,6 +1036,8 @@ void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc) start = start_segno + sbi->segs_per_sec; if (start < end) goto next; + else + end = start - 1; } mutex_unlock(&dirty_i->seglist_lock); -- 2.11.0