Hello,
I've recently experienced a problem with hd geometry on Linux kernel
2.2.17. I've got 2 identical hard drives, set up as LBA on BIOS. BIOS sees
them both with geometry 1245/255/63, while Linux sees the second one as
19857/16/63. I know i can force the kernel to recognize the right geometry
using lilo's append=... feature, but I cannot realize why this is
happening. I've tested it ONLY on Asus motherboards (p2bf and p2b with
latest BIOS version), so maybe this can be a simple hardware problem...
Anyway here's a snip from the dmesg:
hda: FUJITSU MPF3102AH, ATA DISK drive
hdc: FUJITSU MPF3102AH, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hda: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=1245/255/63, UDMA
hdc: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=19857/16/63, UDMA
Now the OS version:
seti:~# cat /proc/version
Linux version 2.2.17 (root@seti) (gcc version 2.95.2 20000220 (Debian
GNU/Linux)) #2 Fri Oct 20
If I switch the 2 hard disks the one put on the secondary IDE channel has
CHS=19857/16/63, no matter which one is, while the first one remains with
1245/255/63.
Let me know...
Cheers,
:raptor
On Wed, 1 Nov 2000, raptor wrote:
> hda: FUJITSU MPF3102AH, ATA DISK drive
> hdc: FUJITSU MPF3102AH, ATA DISK drive
> ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
> ide1 at 0x170-0x177,0x376 on irq 15
> hda: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=1245/255/63, UDMA
> hdc: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=19857/16/63, UDMA
No your BIOS is stupid and does not assume you will have a disk on the
second channel. Thus, one does LBA translation and the other does CHS.
Cheers,
Andre Hedrick
CTO Timpanogas Research Group
EVP Linux Development, TRG
Linux ATA Development
On Wed, Nov 01, 2000 at 02:37:00PM +0100, raptor wrote:
> Hello,
> I've recently experienced a problem with hd geometry on Linux kernel
> 2.2.17. I've got 2 identical hard drives, set up as LBA on BIOS. BIOS sees
> them both with geometry 1245/255/63, while Linux sees the second one as
> 19857/16/63. I know i can force the kernel to recognize the right geometry
> using lilo's append=... feature, but I cannot realize why this is
> happening. I've tested it ONLY on Asus motherboards (p2bf and p2b with
> latest BIOS version), so maybe this can be a simple hardware problem...
> Anyway here's a snip from the dmesg:
>
> hda: FUJITSU MPF3102AH, ATA DISK drive
> hdc: FUJITSU MPF3102AH, ATA DISK drive
> ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
> ide1 at 0x170-0x177,0x376 on irq 15
> hda: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=1245/255/63, UDMA
> hdc: FUJITSU MPF3102AH, 9773MB w/2048kB Cache, CHS=19857/16/63, UDMA
>
> Now the OS version:
> seti:~# cat /proc/version
> Linux version 2.2.17 (root@seti) (gcc version 2.95.2 20000220 (Debian
> GNU/Linux)) #2 Fri Oct 20
>
> If I switch the 2 hard disks the one put on the secondary IDE channel has
> CHS=19857/16/63, no matter which one is, while the first one remains with
> 1245/255/63.
> Let me know...
This is because BIOS only provides info about how it sees the first two
drives (hda and hdb). For hdc and subsequent drives, without the help of
a command line option Linux only can use the untranslated geometry.
--
Vojtech Pavlik
SuSE Labs
On Wed, Nov 01, 2000 at 02:37:00PM +0100, raptor wrote:
: I've recently experienced a problem with hd geometry on Linux kernel
: 2.2.17. I've got 2 identical hard drives, set up as LBA on BIOS. BIOS sees
: them both with geometry 1245/255/63, while Linux sees the second one as
: 19857/16/63.
See the large disk howto, especially the section
"14.2 Nonproblem: Identical disks have different geometry?"
Andries
http://www.win.tue.nl/~aeb/linux/Large-Disk-14.html#ss14.2