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Date: Mon, 23 May 2011 15:09:34 -0500
From: "James R. Van Artsdalen" <james-freebsd-fs2@jrv.org>
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Subject: Re: [RFC] Remove requirement of alignment to track from MBR scheme
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On 5/23/2011 4:55 AM, Andrey V. Elsukov wrote:
> Now it is possible to create MBR partitions with exactly specified
> start offset and size, and they will not be recalculated by kernel.

If a partition is created this way, what will happen if the disk is then
accessed by a FreeBSD kernel before this patch?

If the result is that only newer kernels are supported by the patch, why
not use GPT instead?

Unaligned partitions is a "new" partition table feature, but I'm not
sure how many decades "new" is in this case.  Which other operating
systems can read unaligned partitions (and which can't)?

If the problem is that the kernel is making an undesirable geometry
assumption then perhaps there needs to be a way to change that geometry
assumption.