Re: [GIT PATCH] USB patches for 2.6.33-git

[Linus Torvalds <torvalds@linux-foundation.org>]

On Mon, 14 Dec 2009, Linus Torvalds wrote:
> 
> I'll double-check by reverting it from current -tip, but if you don't hear 
> anything different from me, you can assume that that double-check 
> succeeded and confirms that that commit really is the cause of my printer 
> no longer working.

Confirmed.

With that commit reverted, everything works fine again. So it's definitely 
a2582bd478c13c574d4c16ef1209d333f2a25935, although I have no idea _why_ it 
causes problems.

One thing I note is that it literally changed semantics, as per the 
comment in there. It used to be:

	This walks the driver device list and returns a pointer to the interface
	with the matching minor.

and after that it is

	This walks the bus device list and returns a pointer to the interface
	with the matching minor.

Notice the "driver device list" -> "bus device list" change.

Also notice that the minor number of my 'lp0' device is zero, so I could 
easily imagine that some device without a driver at all or whatever will 
have a zero there, and then it would return the wrong device entirely.

So I really think that commit is very suspect. Not matching against the 
driver that we passed in looks like some total screwup.

But I don't know the code or the use. I do know that reverting it fixes 
it.

		Linus