Booting from external USB drive with kernel 2.6.1x [Solved]

Triptol · Tux's lil' helper Joined: 21 Feb 2004 Posts: 107

I have a big (120Gb) external USB 2.0 drive which I use to boot my office laptop at home. My company only uses stuff from Redmond and they don't allow anything else on the laptop. The external harddisk ensures my fun during the weekends.

Now the thing is that life was nice and good up until 2.6.10 came along. The release notes stated something like a lot of enhancements USB boot users would like. Yeah right: unable to mount root device. No more booting, I'm really pleased. The kernel already tries to boot from /dev/sda3 before the built-in usb-storage driver actually has done its work.

So here I am still using 2.6.9. I have come up with the following:

patch

here

Ideally I'm looking for something I know from the Adaptec SCSI drivers: an official delay time you can enter in the kernel config. Now since that probably is not around I would like to know from people who can get it to work. I'm not too happy applying a 2.2 or 2.4 patch to my 2.6 kernel, but if that is what it takes...

To be more clear: everything worked with kernel 2.6.7, 2.6.8 and 2.6.9. The release of 2.6.10 was where the problems started. The problems are not yet resolved in 2.6.12. And I'm using almost the same config for all kerneles (make oldconfig does some changes though).

thomasmue · n00b Joined: 02 Oct 2003 Posts: 73 Location: MTK,OF,WAK

Hi,

i've done the same with an 80GB external USB 2.0 drive. Found some threads here and there. I also built that initrd, but it comes down to generate enough delay for allowing the usb subsystem to finish. My setup needs 8 seconds, so I have a 10 second delay. Worked with the 2.6.11 kernels.

Triptol · Tux's lil' helper Joined: 21 Feb 2004 Posts: 107

Could you explain how you've created the delay? I have not been able to identify anything but this patch for 2.2 and 2.4. Are you suggesting I should use that? Or did you (hopefully) do somthing else to set the delay?

dsd · Posted: Mon Jun 20, 2005 6:59 pm Post subject:

i contributed a patch for this issue which was accepted into 2.6.11

boot with kernel parameter "rootdelay=5" for a 5 second delay before mounting root
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Triptol · Tux's lil' helper Joined: 21 Feb 2004 Posts: 107

Thanks. This was the answer I was hoping for, will be checking it out in a second. Very cool.

Triptol · Tux's lil' helper Joined: 21 Feb 2004 Posts: 107

Works like a charm!!!

Man this is so great, been waiting for it since 2.6.10... And it has been there since 2.6.11. Why isn't this readily available on the net... Nevermind. Fixed it. Thanks.

dsd · Posted: Mon Jun 20, 2005 9:42 pm Post subject:

it has been discussed a few times in various places and is also documented at Documentation/kernel-parameters.txt
theres not much more you can do for such a small feature
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Triptol · Tux's lil' helper Joined: 21 Feb 2004 Posts: 107

I've done some forum searches and couldn't find anything useful (could be my problem). I've also done some google searches and found a lot of people with the same problem, but no answers... That's why I was amazed.

Is this a Gentoo specific patch or has it been accepted by the kernel development team (it should be)?

dsd · Posted: Tue Jun 21, 2005 5:18 pm Post subject:

it is in mainline
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liljohn118th · n00b Joined: 31 Aug 2005 Posts: 7