[clug] Overriding the BIOS' impression of a disk

Martijn van Oosterhout kleptog at svana.org
Tue Oct 28 18:12:13 EST 2003

Umm, I solved it on one our motherboards by simply not telling the BIOS
about it. Linux saw it fine and went right ahead.

If you jumper the drive to 32GB, chances are you're really limiting it on the
hardware level.

So, I'd suggest just stuffing it in, ignoring whatever the BIOS says and see
if the Linux kernel picks up the right size.

Hope this helps,

On Tue, Oct 28, 2003 at 04:58:44PM +1000, Andrew Pollock wrote:
> Hi,
> I've got an antediluvian motherboard that I recently discovered (the hard 
> way) couldn't handle a disk >32Gb
> This is after a bought a 120G disk at the fair to reinstall it with. So I 
> bought a 40G disk on the weekend and set the jumper to limit the size to 
> 32G and just wore the loss of 8G. Motherboard was happy, booted Linux, and 
> I was happy.
> Until I booted the kernel and saw:
> hda: Host Protected Area detected.
>         current capacity is 66055248 sectors (33820 MB)
>         native  capacity is 78165360 sectors (40020 MB)
> and this got me thinking about some of the kernel parameters, and I went 
> reading ide.txt in the kernel documentation and found:
> Drives are normally found by auto-probing and/or examining the CMOS/BIOS 
> data.
> For really weird situations, the apparent (fdisk) geometry can also be 
> specifiedon the kernel "command line" using LILO.  The format of such 
> lines is:
>         hdx=cyls,heads,sects,wpcom,irq
> or      hdx=cdrom
> where hdx can be any of hda through hdh
> So this got me wondering as to whether I could jumper the 120G drive to 
> 32G so the BIOS will boot it, and then append the real geometry to the 
> kernel and then I could have my cake and eat it?
> Before I go pulling apart multiple machines *again* I thought I'd ask here 
> if anyone else has done this successfully?
> Andrew

Martijn van Oosterhout   <kleptog at svana.org>   http://svana.org/kleptog/
> "All that is needed for the forces of evil to triumph is for enough good
> men to do nothing." - Edmond Burke
> "The penalty good people pay for not being interested in politics is to be
> governed by people worse than themselves." - Plato
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 232 bytes
Desc: not available
Url : http://lists.samba.org/archive/linux/attachments/20031028/d9c420f9/attachment.bin

More information about the linux mailing list