From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Davidsen Subject: Re: unknown partition table starting with 2.6.28 Date: Mon, 01 Feb 2010 15:46:38 -0500 Message-ID: <4B673DAE.3040806@tmr.com> References: <4B51010E.9090800@vorgon.com> <4B51B46A.4080302@anonymous.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4B51B46A.4080302@anonymous.org.uk> Sender: linux-raid-owner@vger.kernel.org To: John Robinson Cc: "Timothy D. Lenz" , linux-raid@vger.kernel.org List-Id: linux-raid.ids John Robinson wrote: > On 15/01/2010 23:58, Timothy D. Lenz wrote: >> I am trying to update my kernel from 2.6.26.8 to the current .32. > [...] >> Starting with .28 I am getting an error about unknown partition table >> for all 3 md's. md0 is boot and main programs, md1 is swap, md2 is >> mostly recordings storage for vdr. All 3 are raid 1 and raid is built >> in. > > Your md devices aren't partitioned so you can quite safely ignore the > warning. See also http://marc.info/?l=linux-raid&m=125797242110594&w=2 To clarify that a bit, the kernel can use several partition formats, and something in the partitions looks like a partition table but not a *valid* partition table. So the kernel warns that it doesn't recognize the table. I suspect that using a different superblock type would change (probably eliminate) this, putting the md information at the start of the partition, of in a bit or whatever makes the kernel happy. The kernel would make us happy if it checked for a valid md superblock at the *end* of the partition, but there may be reasons why that's undesirable. Finally, I'm less willing than John to say you can ignore it, any time something comes close enough to working (in an undesired way) to generate an error message, if there's a simple way to be sure the kernel doesn't try to use random data as a partition table, you might well want to take a step to prevent a problem now. I believe it arises out of all arrays being partitionable recently, again the details don't come to mid, I've been pretty head down on another project since November. -- Bill Davidsen "We can't solve today's problems by using the same thinking we used in creating them." - Einstein