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Cc: Marcel Moolenaar <marcel@freebsd.org>, Poul-Henning Kamp <phk@freebsd.org>,
	freebsd-geom@freebsd.org
Subject: Re: [RFC] Remove requirement of alignment to track from MBR scheme
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On May 23, 2011, at 10:50 AM, Andrey V. Elsukov wrote:
>=20
>> In any event, I'd be tempted to use a #define for 4096 like
>> MBR_MAX_SECTOR_SIZE.
>>=20
>> -	msize =3D MIN(pp->mediasize / pp->sectorsize, UINT32_MAX);
>> +	msize =3D MIN(pp->mediasize / pp->sectorsize, 2 * UINT32_MAX);
>>=20
>> Why this change?  I think that it is in two places.
>=20
> Currently we have limit to msize =3D UINT32_MAX, but partition in MBR =
has
> start offset and size (not end offset). Theoretically it can have size
> that is up to UINT32_MAX sectors, also start offset can be UINT32_MAX.
> And for example, for 4T disk we can have 2 partitions with 2TB size.

Are there any extant examples of this?  The CW is that the maximum size =
for an MBR device is 2TB.

Warner=