Re: [solved] Re: USB device not seen by grub

[Chris Jones]

On Sat, Dec 05, 2009 at 04:16:45AM EST, Vladimir 'φ-coder/phcoder' Serbinenko 
wrote:
> Chris Jones wrote:

Hello Vladimir,

[..]

> > Also, is there any way I can run the grub command line on a system
> > that's already booted, so I can explore its possibities in a context
> > where I have internet access, browse documentation, etc..?
> >
> >   
> I'm working on it but the current problem is that I haven't found a
> syscall in linux to get physical address of a page. Does anyone has a
> suggestion?

Just curious as to whether anything came of this.

One thing further regarding booting a kernel that lives on a USB stick,
is that where it works fine when grub lives on the HDD, oddly enough, I
have not been able to boot that same kernel from a CD image created via
grub-mkrescue.

What I was trying to do is have some means of booting the USB stick in
the event the target machine has a bootable CD/DVD device and does not
let you boot off of a USB device.

When I leave the debug=uhci tracing on, I can see that it is generating
a few screenful of messages at:

  uhci.c:403 ..................

They're all basically the same as previously, giving some details like
flags settings, addresses, completion codes, etc. for what appear to be
USB 'transactions'.

This is followed by exactly three identical sequences of entries at
lines:

  uhci.c:478 ..................
  uhci.c:482 
  uhci.c:493 
  uhci.c:539 
  uhci.c:543

In turn this is followed by a branch back to uhci.c:403 where the same
messages as previously are displayed at the terminal.

I must have let this run for about a half hour and even without tracing,
the boot process never took off.

Again this does not occur when I used the copy of grub that lives on the
hard drive.

The CD images were created with each of the versions of grub that I have
on this machine, 1.96 that comes with debian 'lenny', 1.97 beta3, that
comes with debian 'squeeze' at least when I installed it about two
months ago, and 1.97 beta4 that calme with ubuntu 9.10.

Incidentally, I just checked the exact spelling of grub-mkrescue and
found that there is also a grub-mkimage, so maybe I'm using the wrong
script.

In any event, since I have pretty much abandoned this project of booting
off of a USB stick for the time being, I am not too concerned about this
being fixed or worked around, but I thought I might as well report that
I ran into this problem.

Thank you again for your help.

CJ