RE: The WHY's (RE: ide drive w/dma ... system crash)

Andries.Brouwer@cwi.nl
Wed, 12 May 1999 11:49:28 +0200 (MET DST)


From Nick.BROWN@coe.int Wed May 12 10:48:20 1999

I sat and stared at the code until my eyes went round in circles, and I came
to the following conclusions:

3. Therefore, we should be able to remove probe_cmos_for_drives(). All this
currently does on most systems, is to initialise (thus preempting do_probe)
the CHS numbers for hda and hdb (only) with BIOS-translated geometry, which
(a) may well be completely wrong, (b) is not necessary for the kernel, and
(c) causes a drive to show different geometry in dmesg depending on whether
it's hda or hdc.

Yes, we agree entirely, except perhaps concerning the timing.
Even though probe_cmos_for_drives() returns the wrong results
on your machine (and mine), it is correct in the majority of the
cases. And there is not yet a new version of LILO, not even a
careful description of what the new kernel interface is going
to be. So, for today, we must leave things as they are, perhaps
polish the kernel source a bit - it is still possible to reduce
the number of cases where the kernel is wrong without introducing
problems for others - next design and implement a partition ioctl,
next come with new versions of LILO and fdisk that use the new
interface, next wait for five years to make sure no old LILO's
are around, and only then remove the present probe_cmos_for_drives().
And there will be screams five years from now, just like today
we hear people that still use 1993 ZMAGIC binaries.

From hedrick@Astro.Dyer.Vanderbilt.Edu Wed May 12 06:23:13 1999

Well we bang heads again.

By now you know me. Don't worry if my words are not friendly.
I just keep pointing out what I consider bugs.

The hdparm man page says

-i Display the identification info that was obtained
from the drive at boot time, if available.

but presently it is

-i Display the identification info that was obtained
from the drive at boot time and modified by the kernel.

I consider the new output much less valuable than the old.
At present there is no mechanism anymore for obtaining the
identification info that was obtained from the drive at boot time.
That is a pity.

Andries

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