From: Jes Sorensen <Jes.Sorensen@xxxxxxxxxx> 'max_discard_sectors' is in sectors, while 'stripe' is in bytes. This fixes the problem where DISCARD would get disabled on some larger RAID5 configurations (6 or more drives in my testing), while it worked as expected with smaller configurations. Fixes: 620125f2bf8 ("MD: raid5 trim support") Signed-off-by: Jes Sorensen <Jes.Sorensen@xxxxxxxxxx> --- This bug has been present since RAID5 DISCARD was introduced, so it applies to stable as well. drivers/md/raid5.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index b4f02c9..7f770b0 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -7014,8 +7014,8 @@ static int raid5_run(struct mddev *mddev) } if (discard_supported && - mddev->queue->limits.max_discard_sectors >= stripe && - mddev->queue->limits.discard_granularity >= stripe) + mddev->queue->limits.max_discard_sectors >= (stripe >> 9) && + mddev->queue->limits.discard_granularity >= stripe) queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); else -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html