USB4BSD release candidate number 3 - request for review

[Rink Springer]

On Wed, Nov 05, 2008 at 02:18:17AM -0700, M. Warner Losh wrote:
> In message: <200811050914.44225.hselasky at c2i.net>
>             Hans Petter Selasky <hselasky at c2i.net> writes:
> : On Wednesday 05 November 2008, Lars Engels wrote:
> : > Mounting a umass device, removing it and doing an 'ls' on the mountpoint
> : > freezes the system, I thought this should not happen with the new stack?
> : 
> : It is not a USB problem. It is the CAM layer that is hanging on the disk.
> 
> Sure it is CAM layer and not buffer cache or filesystem code?

Well, the CAM layer problem will immediately first - it does not like
CAM busses disappearing. Once this is fixed or avoided and the problem
still shows up, we can blame buffer cache / filesystem code.

As I suggested before, a good fix is to create one CAM bus per USB root
hub, and use that to attach all umass devices to. This will also get rid
of the one-bus-per-umass-device which is visually unappealling.

Regards,
Rink

-- 
Rink P.W. Springer                                - http://rink.nu
"Anyway boys, this is America. Just because you get more votes doesn't
 mean you win." - Fox Mulder