[mythtv-users] OT: Problem mounting root from an sata drive with 2.6.5 kernel and libata

[Gerald Schepens]

Is anyone running a 2.6.x kernel with an sata drive as root, using the 
libata driver for the sata drive?  I'm having a time trying to get root 
to mount.  It may be due to the libata driver naming the drive devices 
differently from my current driver under 2.4.20. 

The issue seems to be that I'm not passing the correct "root=" parameter 
to the kernel.  I used to use root=LABEL=/ but that doesn't work.  I've 
since tried just about every variation I can think of for other 
possibilities, but I have gotten nowhere so far.

I was using the Promise 378 serial ATA driver, ft3xx.o, which is a 
partial-source proprietary driver that I was eager to get rid of.  With 
that driver, my sata drive is /dev/sda, with the various partitions on 
it as /dev/sda1 (/boot) and /dev/sda2 (root).  I've googled that various 
people have used /dev/md0, /dev/atadrive/d0p2, or /dev/hdg2, or ...

The controller gets detected, as does the (single) drive, which is 
mentioned in a message: "scsi1: WD0200...".  md runs an autodetect on 
raid arrays and while it doesn't say that it sees anything, it doesn't 
say anything under the 2.4.20 kernel either.  The first evidence of 
trouble is that mount gets an error 22 while trying to mount an ext3 
volume.  (This is if I give "root=/dev/hda2", for instance.  If I start 
with a "root=" that I'm not confident actually is a valid drive / device 
partition, such as /dev/hde2,  it's an error 6 from mount.)  Then I get 
a kernel panic because the kernel could not mount the root volume.

A quick rundown of the hardware setup:  It's an Asus P4PE motherboard, 
with two IDE controllers and the Promise 378 SATA controller.  On IDE 1, 
I have one hard drive (/dev/hda under 2.4.20).  On IDE 2, I have a CDR/W 
(/dev/scd0) and a DVD-R/W (/dev/scd1).  The SATA controller controls one 
SATA drive, which is "1+0 striped" but not mirrored (/dev/sda).  I have 
been running the two CD / DVD drives as SCSI emulations.

It's possible that the libata / Promise modules are trying to read the 
drive in a format that renders the data already present on it 
unintelligible.  Thus far I've used the proprietary driver and maybe the 
libata setup won't play nice with the data already present on the disk.  
Comments?

I've googled, I've fiddled around, I don't know what to do next.  My 
only recourse at this point is to throw the question out there and hope 
that one of you has a similar setup and has had more success than I have 
had.

Other questions that I might as well throw out now, since if I get the 
2.6.5 kernel working they'll be the next things I'm going to want to know: 

- How good is the ivtv support with kernel 2.6.x?  (I run a pvr350 as 
capture / TV out card.)
- How about lirc under 2.6.x?

Thanks for your collective wisdom and patience,

Gerald Schepens