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

[David]

Gerald Schepens wrote:

> 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.

No, sorry. I boot from pata - other than that:
I'm using 2.6.4 with libata, Via SATA + PATA drives lvm2'ed for /myth 
though.
Typically I expect you'll have 4 pata channels -> hda,hdb on ide0 
,hdc,hdd on ide1
so try /dev/hde or hdf as your sata (that's what mine is) on ide2 (I see 
later you've begun)

> 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 ...

/dev/sda is sata as scsi isn't it?

> 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

physical controllers or your usual 2 channels per motherboard?
(Don't controllers usually/often have two channels.)

> 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.

hde hdf hdg hdh may be on controller 2
so try hdi for sata

> 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?

Sounds like a reasonable comment.
stick an ATA disk in and boot 2.6 from it sounds like an easy way to 
find out - at least dmesg/fdisking will show you partitions etc.
In fact I *think* knoppix just came out with a 2.6 based CD - you can 
boot from that dead easily!!
 www.knoppix.org
(Yup, re-reading prior to posting and this sounds like your best bet to 
read dmesg from a 2.6 kernel without diddling *any* hardware.)

> 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.)

I love it - from my sample of 1 + very occasional observations 
(including posts on the ivtv list) I think its quite a bit more stable 
than 2.4

> - How about lirc under 2.6.x?

There were problems last time I looked at using the PVR's RC under 2.6 - 
IIRC that maybe fixed - search the archives.
I use homebrew trans/recv and it's fine.

>
> Thanks for your collective wisdom and patience,

's ok :)

If you find any more about 2.6 and Myth etc then there is a wiki at 
www.mythtv.info
It's unofficial and has been the subject of much controversy (see 
archives) but you may want to contribute any findings back there in 
preparation for the inevitable increase in Myth/2.6 FAQs (+ as you said, 
some of the sata stuff is pretty off topic for myth but fine on the wiki)

David