| From b2176a1dfb518d870ee073445d27055fea64dfb8 Mon Sep 17 00:00:00 2001 |
| From: Nigel Croxon <ncroxon@redhat.com> |
| Date: Tue, 16 Apr 2019 09:50:09 -0700 |
| Subject: md/raid: raid5 preserve the writeback action after the parity check |
| |
| From: Nigel Croxon <ncroxon@redhat.com> |
| |
| commit b2176a1dfb518d870ee073445d27055fea64dfb8 upstream. |
| |
| 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 <lkp@intel.com> |
| |
| Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
| Signed-off-by: Nigel Croxon <ncroxon@redhat.com> |
| Signed-off-by: Song Liu <songliubraving@fb.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/md/raid5.c | 10 +++++++++- |
| 1 file changed, 9 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/md/raid5.c |
| +++ b/drivers/md/raid5.c |
| @@ -3878,7 +3878,7 @@ static void handle_parity_checks6(struct |
| /* 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++; |
| @@ -3903,6 +3903,14 @@ static void handle_parity_checks6(struct |
| 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); |
