Hello,

I checked again under NetBSD-1.6.2 and NetBSD-1.6ZL and I agree with you: it 
must be a buggy BIOS :(

NetBSD-1.6.2 does not effectively report the total sectors numbers as 
reports the BIOS, while NetBSD-1.6ZL does:

   1.6ZL # sysctl machdep.diskfinfo
           machdep.diskfinfo = 80:2846(1022/255/63),2 wd0:80

The only weird thing is that the BIOS displays correct information about 
total sectors number:

   Primary Hard Drive WDC WD84AA
                      type AUTO
                      total sectors: 16514064
                      maximum capacity: 8455 MB


 >> Maybe fdisk should use the disk size from the 'netbsd geometry'
 >> as the limit for the partitions.

Yes, It could be nice, espacially on old machines where NetBSD used to work 
(even with buggy BIOS).


So this PR is only noise, sorry for that; can semeone close this PR ? Does 
it need I add some informations before it can be closed ?

Regards,

Pierre Bourgin



andrej misovic a écrit:
> yes, it's problem with bios,
> you should set that by hand,
> or you probably did that..
> 
>         ado
> 
> David Laight wrote:
> 
>>>> Synopsis:       fdisk does not use (report) correct hard drive BIOS 
>>>> geometry
>>>
>>
>>
>>> On my old DELL XPS D266 (PII-266 MHz) and a hard drive of 8 GB,
>>> 'fdisk wd0' reports an invalid total numbers of sectors (2846
>>> instead of something near 16514064):
>>
>>
>>
>>> # fdisk wd0
>>> Disk: /dev/rwd0d
>>> NetBSD disklabel disk geometry:
>>> cylinders: 16383, heads: 16, sectors/track: 63 (1008 sectors/cylinder)
>>> total sectors: 16514064
>>>
>>> BIOS disk geometry:
>>> cylinders: 1022, heads: 255, sectors/tracks: 63 (16035 sectors/cylinder)
>>> total sectors: 2846
>>
>>
>> I suspect this is a buggy bios, since that sector count comes from
>> a bios call done during system initialisation.
>>
>> 'sysctl machdep.diskinfo' should report the values being used.
>>
>> Maybe fdisk should use the disk size from the 'netbsd geometry'
>> as the limit for the partitions.
>>
>> 1.6.2 does no validatoon on the numbers at all...
>>
>>     David
>>
>