Re: HEADS UP: Check your devices' UDMA settings - *TEMPORARY* *WORKAROUND*

On 06/04/2011 15:53, Ric Moore wrote:
On Wed, 2011-04-06 at 15:04 +1000, Basil Chupin wrote:
On 05/04/2011 15:51, Basil Chupin wrote:
It appears that Bug #195221 has suddenly come back -- see

This bug re-appeared on 1 April (my time, Australia, East Coast)
because the previous day my logs showed that the UDMAs were being set
correctly. The only thing which I can see is that on 1 April there was
a kernel firmware upgrade but as I know nuffin' about kernels (or
majors or even captains) this upgrade may have nothing to do with it.

What the above Bug is about is that even though your HDD, for example,
can do UDMA 133 the UDMA in fact gets set to UDMA 33 because some
check concludes incorrectly that the device is connected with a
40-wire cable. Here is an example I just took from my dmesg log file:


The temporary workaround for this problem is to add to the boot
parameters the following: libata.force=X:80c

where X is the IDE line which is being affected by this UDMA problem. In
my case, the devices on line #2 are affected so I use libata.force=2:80c
and now the HDD and the DVDRW are being set to UDMA 100& 100, respectively.

Using 'libata.force=X:80c' is working because libata is actually
statically embedded in the kernel; if it was not then you would use

(Now I have to go and read up on grub 2 to see how I can insert this
workaround in grub without having to add this everything to the boot
parameters at boot time.)
Glad to see you beat that bugger-bear! Man, it has been an uphill climb
for you to get this far. I tip my wayward4now hat at ya! :) Ric

I do it for humanity's sake, I tell you! Tirelessly and without any consideration of myself! For no reward, except perhaps for a gratuitous small, simple, single, spoken quietly (more like whispered...) - "Thank you."

(I'm starting to believe this shit so I better stop :-) !)

Now all I need is for someone to tell me how to get this fix into grub so that it is executed whenever I boot up. I read the grub2 doco and I am buggered if I can get grub2 to automatically boot with this fix in its boot parameters :-( . Had no hassles with openSUSE 11.4 which is using the old grub: just type in the fix on a line in the menu.lst and reboot. But grub2? Oh no, thank you very mucho! The doco for grub2 in Ubuntu docs speak of The Startup Manager which 'will do all sorts of things' for you if you want to change the parameters in grub2. BS! You have a choice of changing ~4 parameters in grub2. Sheesh! As usual, something simple is turned into something only geeks can understand :-( .


"I believe what I am programmed to believe."
A robot in Futuruma

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