[CentOS] USB-3.0 on C6.5 ??

[Fred Smith]

On Sat, May 24, 2014 at 01:54:13PM +0200, Mihai T. Lazarescu wrote:
> On Fri, May 23, 2014 at 09:52:11PM -0400, Fred Smith wrote:
> 
> > On Fri, May 23, 2014 at 09:19:49AM -0500, Johnny Hughes wrote:
> > > On 05/22/2014 09:09 PM, Fred Smith wrote:
> > > > Just wondering if there are any known issues with USB 3.0 storage devices
> > > > in Centos 6.5??
> > > >
> > > > I just got one of these: http://www.newegg.com/Product/Product.aspx?Item=N82E16817332028
> > > >
> > > > it does either esata or USB 3.0. My new motherboard (ASUS M5A99X EVO
> > > > R2.0) supports both, so I've tried both (of course, can't have a feature
> > > > without at least giving it a whirl! :)). esata seems to work fine,
> > > > I can copy gigs 'n gigs of data to it using the esata connection.
> > > >
> > > > however, with USB3 it works for a bit then something goes wonky...
> > > > After copying some hundreds of megabytes (and I don't know if it is a
> > > > consistent number or not) suddenly my C6 box starts reporting write
> > > > errors.
> > > >
> > > > some investigation shows that /dev/sdc (and /dev/sdc1) no longer exist
> > > > on the system. it takes a reboot to get it back. After which it'll
> > > > work for a while then the same thing all over again. I've tried a
> > > > different USB 3.0 cable but it makes no difference.
> > > >
> > > > Anyone got ideas on this?
> 
> You may try using a newer kernel from ElRepo (currently 3.14.4):
> 
>     http://elrepo.org/tiki/kernel-ml
> 
> If it were a driver problem, maybe it was fixed.
> 
> Mihai

I may have to try that, but not quite yet.

I just ran some more experiments:
1. using a USB 2.0 cable on a USB 2.0 port. couldn't make it fail.
2. using a USB 2.0 cable on a USB 3.0 port. hasn't failed yet,
   still testing.

the USB3 functionality comes from a different chip than the USB2:
03:00.0 USB controller: ASMedia Technology Inc. ASM1042 SuperSpeed USB Host Controller
whereas USB2 comes from an AMD SB9x chip.

I'm thinking that it USB2 works, even when managed by a USB3 chipset,
should mean something. but I"m not sure if it means that simply slowing
it down solves the problem, or if it means that we're not using all
the functionality of the chipset, bypassing something buggy. or maybe
bypassing bugs in the ASMedia kernel driver.

-- 
---- Fred Smith -- fredex at fcshome.stoneham.ma.us -----------------------------
  "And he will be called Wonderful Counselor, Mighty God, Everlasting Father,
  Prince of Peace. Of the increase of his government there will be no end. He 
 will reign on David's throne and over his kingdom, establishing and upholding
      it with justice and righteousness from that time on and forever."
------------------------------- Isaiah 9:7 (niv) ------------------------------