In func analyse_stripe, it added to_read/to_write by sh->dev[i]->toread/towrite. If stripe failed, in func handle_failed_stripe it decreased to_read/to_write also by sh->dev[i]->toread/towrite. But between func analyse_stripe and handle_failed_stripe, toread/towrite can change.So the to_read/to_write maybe less zero. For example, if to_write was less zero,it may introduce a bug in func async_xor: 'BUG_ON(src_cnt <= 1);'. So after handle_failed_stripe,it should use 'to_read/to_write > 0' instead of judging 'to_read/to_write'. Signed-off-by: Jianpeng Ma <majianpeng@xxxxxxxxx> --- drivers/md/raid5.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index a56aa5b..554ca9e 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2641,7 +2641,7 @@ static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s, (s->failed >= 2 && fdev[1]->toread) || (sh->raid_conf->level <= 5 && s->failed && fdev[0]->towrite && !test_bit(R5_OVERWRITE, &fdev[0]->flags)) || - (sh->raid_conf->level == 6 && s->failed && s->to_write))) { + (sh->raid_conf->level == 6 && s->failed && s->to_write > 0))) { /* we would like to get this block, possibly by computing it, * otherwise read it if the backing disk is insync */ @@ -3471,8 +3471,8 @@ static void handle_stripe(struct stripe_head *sh) * parity, or to satisfy requests * or to load a block that is being partially written. */ - if (s.to_read || s.non_overwrite - || (conf->level == 6 && s.to_write && s.failed) + if (s.to_read > 0 || s.non_overwrite + || (conf->level == 6 && s.to_write > 0 && s.failed) || (s.syncing && (s.uptodate + s.compute < disks)) || s.replacing || s.expanding) @@ -3519,7 +3519,7 @@ static void handle_stripe(struct stripe_head *sh) * 2/ A 'check' operation is in flight, as it may clobber the parity * block. */ - if (s.to_write && !sh->reconstruct_state && !sh->check_state) + if (s.to_write > 0 && !sh->reconstruct_state && !sh->check_state) handle_stripe_dirtying(conf, sh, &s, disks); /* maybe we need to check and possibly fix the parity for this stripe -- 1.7.9.5 ?韬{.n?????%??檩??w?{.n???{炳盯w???塄}?财??j:+v??????2??璀??摺?囤??z夸z罐?+?????w棹f