On Tue, 5 Jun 2007, Ahmed Hussien wrote:
> Hi there;
> I have an ATA hard disk permanently connected to my system using a "USB
> to IDE" adapter. I use this hard disk for my data files, so I don't need
> to access it at boot time. I have been using it for a long time, and It
> worked fine with fedora core 6 (kernel 2.6.20). It was recognized
> immediately, automatically mounted when I log in.
> Yesterday, I installed fedora 7 (kernel 2.6.21). While booting I get the
> following error a few times
>
> "device descriptor read/64, error -71"
>
> and the hard disk is not recognized, and no device files are created in
> the /dev directory.
> Thinking I had a problem with my USB hardware, I tried connecting a 2
> GBytes Kingston Flash disk to another USB port on my system. Not only
> did the USB Flash disk work, but also the USB hard disk (that didn't
> work initially) was immediately recognized, and mounted.
> It seems all what was needed was for the USB kernel module to rescan the
> USB bus.
> I am not really good at such stuff, but it looks to me as if it may be a
> timing problem, or something needs to be done before attempting to scan
> the USB bus.
My own guess is that it's not a timing problem or anything like that.
It's interference of some sort caused by too many things going on all
at once during bootup. But that's just a guess.
As for needing to do something extra before scanning the bus -- if that
were true then your drive would never work, because nothing extra ever
gets done!
It sure would be interesting to know why it happens under 2.6.21 but
not 2.6.20. Can you try building a vanilla kernel of each release
(from kernel.org, not Fedora's modified versions) and booting them with
your FC7 system? Perhaps the difference lies not in the kernel itself
but in the user programs; if that's so then 2.6.20 will fail.
> Does anyone know a way that would get this hard disk recognized
> automatically at boot time??
No. Since we don't know what's wrong, we don't know how to fix it.
But you can work around the problem. In your startup scripts you could
do this:
rmmod ehci-hcd
sleep 10
modprobe ehci-hcd
Replace the 10 with whatever delay is needed for things to settle down
and start working properly.
Alan Stern
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