From: NeilBrown <neilb@suse.de>
Date: Wed, 30 Dec 2009 01:08:49 +0000 (+1100)
Subject: md: Fix unfortunate interaction with evms
X-Git-Tag: v2.6.33-rc3~43^2~4
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cbd1998377504df005302ac90d49db72a48552a6;p=pandora-kernel.git

md: Fix unfortunate interaction with evms

evms configures md arrays by:
  open device
  send ioctl
  close device

for each different ioctl needed.
Since 2.6.29, the device can disappear after the 'close'
unless a significant configuration has happened to the device.
The change made by "SET_ARRAY_INFO" can too minor to stop the device
from disappearing, but important enough that losing the change is bad.

So: make sure SET_ARRAY_INFO sets mddev->ctime, and keep the device
active as long as ctime is non-zero (it gets zeroed with lots of other
things when the array is stopped).

This is suitable for -stable kernels since 2.6.29.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
---

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