From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adam Kwolek Subject: [PATCH] imsm: FIX: Do not write check-point '0' Date: Fri, 29 Apr 2011 16:29:21 +0200 Message-ID: <20110429142921.12605.54696.stgit@gklab-128-013.igk.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: neilb@suse.de Cc: linux-raid@vger.kernel.org, dan.j.williams@intel.com, ed.ciechanowski@intel.com, wojciech.neubauer@intel.com List-Id: linux-raid.ids When 2 arrays are configured in container and arrays are reassembled during rebuild or initialization, checkpoint for one array can be reset. It depends on arrays assembly order. Scenario: 1. Create 2 arrays (e.g. raid5) 2. Add spare to container 3. Degrade arrays /rebuild starts on array #1 and continues to n%/ 4. Reassembly arrays 5. Rebuild starts on array #2 /because of assembly order/ from 0% 6. On first checkpoint stored for array #2 (non 0 value), checkpoint for array #1 is cleared /it is delayed rebuild in md, so progress is 0/ 7. Rebuild on #1 starts from n% /it was configured before checkpoint was cleared/. Any next reassembly during rebuild of #2 array (after p.6) causes checkpoint information lost for array #1. Solution is not store checkpoint for progress == 0. Checkpoint is set to 0 when rebuild/initialization starts. Note: Please apply this patch on master branch. Signed-off-by: Adam Kwolek --- super-intel.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/super-intel.c b/super-intel.c index 83135a6..0956c92 100644 --- a/super-intel.c +++ b/super-intel.c @@ -5479,6 +5479,7 @@ mark_checkpoint: * curr_migr_unit needs updating */ if (units32 == units && + units32 != 0 && __le32_to_cpu(dev->vol.curr_migr_unit) != units32) { dprintf("imsm: mark checkpoint (%u)\n", units32); dev->vol.curr_migr_unit = __cpu_to_le32(units32);