From b2176a1dfb518d870ee073445d27055fea64dfb8 Mon Sep 17 00:00:00 2001 From: Nigel Croxon Date: Tue, 16 Apr 2019 09:50:09 -0700 Subject: md/raid: raid5 preserve the writeback action after the parity check The problem is that any 'uptodate' vs 'disks' check is not precise in this path. Put a "WARN_ON(!test_bit(R5_UPTODATE, &dev->flags)" on the device that might try to kick off writes and then skip the action. Better to prevent the raid driver from taking unexpected action *and* keep the system alive vs killing the machine with BUG_ON. Note: fixed warning reported by kbuild test robot Signed-off-by: Dan Williams Signed-off-by: Nigel Croxon Signed-off-by: Song Liu --- drivers/md/raid5.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'drivers/md') diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index b5742d07662d..7fde645d2e90 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -4191,7 +4191,7 @@ static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh, /* now write out any block on a failed drive, * or P or Q if they were recomputed */ - BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */ + dev = NULL; if (s->failed == 2) { dev = &sh->dev[s->failed_num[1]]; s->locked++; @@ -4216,6 +4216,14 @@ static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh, set_bit(R5_LOCKED, &dev->flags); set_bit(R5_Wantwrite, &dev->flags); } + if (WARN_ONCE(dev && !test_bit(R5_UPTODATE, &dev->flags), + "%s: disk%td not up to date\n", + mdname(conf->mddev), + dev - (struct r5dev *) &sh->dev)) { + clear_bit(R5_LOCKED, &dev->flags); + clear_bit(R5_Wantwrite, &dev->flags); + s->locked--; + } clear_bit(STRIPE_DEGRADED, &sh->state); set_bit(STRIPE_INSYNC, &sh->state); -- cgit v1.2.3-59-g8ed1b