Patch for 2.4 USB serial

[Greg KH]

On Tue, Mar 23, 2004 at 07:54:37PM -0800, Pete Zaitcev wrote:
> > > However, what about the port->open_count?
> > > It is manipulated without any locking, it seems. 
> > 
> > Actually it can be gotten rid of entirely I think.  The reference count
> > of the object is now handled properly, so open_count is pretty much
> > pointless.  Now we are still relying on the fact that open() can't race
> > with disconnect() from the USB bus, which in real-life is probably ok,
> 
> You cannot just get rid of it if you still want to call component
> driver's ->open only once. Something has to count, and reference
> counts do not match open counts, so you have to keep a counter for it.
> An alternative would be to pass all upper level opens through to
> component drivers, which would just push open counts down a level.
> IIRC, we did it before, but migrated to the current scheme.
> So, the open count stays. Since it stays, it has to be protected.

Ah, good point, you are correct.

> > How about a patch against a clean 2.4 tree?  This is against the latest
> > fedora 2.4 kernel, right?
> 
> I was going to send it out after 2.4.26, but I can send it now if you
> want.

After 2.4.26 is fine, I'm in no hurry.

thanks,

greg k-h