From: NeilBrown Date: Tue, 9 Feb 2010 01:31:47 +0000 (+1100) Subject: md: fix 'degraded' calculation when starting a reshape. X-Git-Tag: v2.6.33-rc8~35^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9eb07c259207d048e3ee8be2a77b2a4680b1edd4;p=pandora-kernel.git md: fix 'degraded' calculation when starting a reshape. This code was written long ago when it was not possible to reshape a degraded array. Now it is so the current level of degraded-ness needs to be taken in to account. Also newly addded devices should only reduce degradedness if they are deemed to be in-sync. In particular, if you convert a RAID5 to a RAID6, and increase the number of devices at the same time, then the 5->6 conversion will make the array degraded so the current code will produce a wrong value for 'degraded' - "-1" to be precise. If the reshape runs to completion end_reshape will calculate a correct new value for 'degraded', but if a device fails during the reshape an incorrect decision might be made based on the incorrect value of "degraded". This patch is suitable for 2.6.32-stable and if they are still open, 2.6.31-stable and 2.6.30-stable as well. Cc: stable@kernel.org Reported-by: Michael Evans Signed-off-by: NeilBrown --- Reading git-diff-tree failed