raid5: update analysis state for failed stripe

handle_failed_stripe() makes the stripe fail, eg, all IO will return
with a failure, but it doesn't update stripe_head_state. Later
handle_stripe() has special handling for raid6 for handle_stripe_fill().
That check before handle_stripe_fill() doesn't skip the failed stripe
and we get a kernel crash in need_this_block.  This patch clear the
analysis state to make sure no functions wrongly called after
handle_failed_stripe()

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 15ef2c641b2b93e96004d073463fdcfaaaaceab4..2105e5f1fd314b724e3c6d5206ffaf9f8678fac4 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3150,6 +3150,8 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
                        spin_unlock_irq(&sh->stripe_lock);
                        if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
                                wake_up(&conf->wait_for_overlap);
+                       if (bi)
+                               s->to_read--;
                        while (bi && bi->bi_iter.bi_sector <
                               sh->dev[i].sector + STRIPE_SECTORS) {
                                struct bio *nextbi =
@@ -3169,6 +3171,8 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
                 */
                clear_bit(R5_LOCKED, &sh->dev[i].flags);
        }
+       s->to_write = 0;
+       s->written = 0;
 
        if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
                if (atomic_dec_and_test(&conf->pending_full_writes))