On 07/11/2011 01:51 PM, Connie Sieh wrote:
> On Mon, 11 Jul 2011, Yasha Karant wrote:
>
>> I have been attempting to get a working USB 3 external harddrive
>> subsystem. Thus far, no go.
>>
>> Here is what I have found:
>>
>> 1. kernel 2.6.38.6-26.rc1.fc15.x86_64 works fine for USB 3, but
>> requires gcc 4.6 to build any kernel modules; RHEL 6 (SL 6, CentOS 6)
>> uses gcc 4.4. Thus, neither the Nvidia nor VirtualBox modules will
>> build on on a RHEL 6 system.
>>
>> 2. kernel 2.6.33.3-85.fc13.x86_64 that was built with gcc 4.4 works,
>> but only partially -- please see point 3.
>>
>> 3. After installing both of the above kernels, kernel
>> 2.6.32-131.2.1.el6.x86_64 now functions essentially the same as
>> 2.6.33.3-85.fc13.x86_64 . The device is recognized and /dev/sde and the
>> partitions thereunder /dev/sde1 ... are created. However, no automount
>> points are created that were created with 2.6.38.6-26.rc1.fc15.x86_64 .
>> Moreover, fdisk /dev/sde fails. A reading of dmesg shows numerous
>> exceptions and diagnostics that are documented in USB 3 linux kernel
>> development hits during a web search and that evidently were fixed in
>> later kernels (such as 2.6.38.6-26.rc1.fc15.x86_64 ). I am not going to
>> reproduce these here, but suffice it to say that the /dev/sde set
>> appears, vanishes as evidenced by the output of /ls/dev/sd* and then
>> reappears.
>>
>> Note that all of the hardware and systems commands, etc., work on a USB
>> 2 port on this system.
>>
>> An attempt to build from source 2.6.38.6-26.rc1.fc15.x86_64 using the
>> gcc 4.4 system of SL6 is my next step, rpmbuild --rebuild
>> kernel-2.6.38.6-26.rc1.fc15.src.rpm .
>>
>> Yasha Karant
>>
>
> Since usb 3 worked for your chipsets on a prior RHEL 6 kernel and does
> not work on the current RHEL 6 kernel . I suggest you search
> bugzilla.redhat.com looking for your issue. If you do not find the issue
> please bugzilla it.
>
> -Connie Sieh

From:  https://bugzilla.redhat.com/show_bug.cgi?id=683681

usb3 is still a little flaky on error recovery.  That is what happened 
here.
The endpoint (device) stalled for whatever reason and it had trouble 
resetting
the port back to a good known state.

A bit later in the thread:

I've updated to 6.1beta 2.6.32-122.el6.x86_64 and
now the USB3 card does not see anything connected
to it.

And still a bit later:

What happens if you unplug the hard drive, reboot the machine, login, 
the plug
in the harddrive?  Is that more stable?

later in the bugzilla thread:

RHEL Product and Program Management 2011-04-03 22:49:52 EDT

Since RHEL 6.1 External Beta has begun, and this bug remains
unresolved, it has been rejected as it is not proposed as
exception or blocker.

Red Hat invites you to ask your support representative to
propose this request, if appropriate and relevant, in the
next release of Red Hat Enterprise Linux.

Cheers,
Don

End thread.

Unlike RHEL 6 and perhaps CentOS 6, SL 6 has additions that solve real 
problems so that real hardware can be used in the real world of hard 
science.  I think that I have come close to establishing that later 
releases of the Linux kernel (e.g., 2.6.38) actually solve the USB 3 
problem.  Is it possible for SL 6 to offer a solution as a 
add-on/extended but real solution, as SL 6 supports hardware beyond 
standard RHEL 6?

Yasha Karant