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Message-ID: <38b2ab8a0804101215t3ac692c3k2a2d955ca17eba9b@mail.gmail.com>
Date: Thu, 10 Apr 2008 21:15:15 +0200
From: "Francis Moreau" <francis.moro@gmail.com>
To: "linux-os (Dick Johnson)" <linux-os@analogic.com>
Subject: Re: Disk geometry from /sys
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <Pine.LNX.4.61.0804100804260.25651@chaos.analogic.com>
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Hi,

On Thu, Apr 10, 2008 at 2:22 PM, linux-os (Dick Johnson)
<linux-os@analogic.com> wrote:
>
>  It becomes, as you say contentious, because with disk drives
>  manufactured during the past ten or so years, anything about
>  the physical geometry is fictitious. The PC BIOS continues to
>  calculate C/H/S because that's what BIOS interrupt 0x13 uses
>  to boot the machine. The boot code needs to know what the
>  BIOS claims or else it may fail to boot. However, once Linux
>  is up, there are no C/H/S unless they were invented --and
>  hopefully, the same as what the BIOS claims.
>

Some bootloaders want the partition starts to be aligned on a
cylinder size boundary. Try for example to setup a disk partition
table by using parted. It almost always complains about the
the size of the parts I try to create and suggest me others. The
same stands for sfdisk except that it just gives you some
warnings.

Thanks
-- 
Francis