From: Zhao Lei <zhaolei@xxxxxxxxxxxxxx> commit 503785306d182ab624a2232856ef8ab503ee85f9 upstream. reada_zone->end is end pos of segment: end = start + cache->key.offset - 1; So we need to use "<=" in condition to judge is a pos in the segment. The problem happened rearly, because logical pos rarely pointed to last 4k of a blockgroup, but we need to fix it to make code right in logic. Signed-off-by: Zhao Lei <zhaolei@xxxxxxxxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> --- fs/btrfs/reada.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c index 619f92963e27..49b3fb73ffbf 100644 --- a/fs/btrfs/reada.c +++ b/fs/btrfs/reada.c @@ -265,7 +265,7 @@ static struct reada_zone *reada_find_zone(struct btrfs_fs_info *fs_info, spin_unlock(&fs_info->reada_lock); if (ret == 1) { - if (logical >= zone->start && logical < zone->end) + if (logical >= zone->start && logical <= zone->end) return zone; spin_lock(&fs_info->reada_lock); kref_put(&zone->refcnt, reada_zone_release); @@ -679,7 +679,7 @@ static int reada_start_machine_dev(struct btrfs_fs_info *fs_info, */ ret = radix_tree_gang_lookup(&dev->reada_extents, (void **)&re, dev->reada_next >> PAGE_CACHE_SHIFT, 1); - if (ret == 0 || re->logical >= dev->reada_curr_zone->end) { + if (ret == 0 || re->logical > dev->reada_curr_zone->end) { ret = reada_pick_zone(dev); if (!ret) { spin_unlock(&fs_info->reada_lock); -- 2.7.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html