Duncan Sands wrote: > On a slightly different topic, if you have > more than one modem, don't they end up being assigned interface numbers in a > random order - how to deal with that?
Assuming each device has a unique ESI you should be able to tell them apart bu reading /proc/net/atm/devices. > > Thats why my patch changes ATM_ITF_ANY to just mean "the first interface on > > the list" That way ATM_ITF_ANY doesn't change behavior for the common case > > where you have a single device. > > But what does this change buy you? [...] > Or is the point that you can simplify the code a lot? Exactly -- it means you don't have to fix it. I think the fact that the kernel seems to crash if you actually try to use it speaks to how useful people have found ATM_ITF_ANY in the past. :-) Let's just get rid of it rather than dealing with the locking mess. > In the common case of a single > device, the behaviour would be the same. Exactly. And if you have more than one device the behavior never made much sense so my patch doesn't make it any worse. > It's less clear to me that recycling interface numbers faster is the real > solution - I think that if you never have more than one device plugged in at a time then you should only have "interface 0". Anything else is needlessly confusing. If one day your (single) ethernet card got detected as "eth12" wouldn't you find that a little odd? > isn't that just papering over the problem that interface numbers are > meaningless, > and get handed out rather randomly? It would be better if devices could be > specified by some sort of universally meaningful thing, like the MAC address > (do > ATM cards have these - the speedtouch modems do, and store it in esi). Yes, in general although not every driver grabs ESI correctly. I think the situation is similar to ethernet -- the stack assigns the "meaningless" interface numbers in order and for 99.9% of people that's good enough. For the corner cases where you do care (like you have multiple usb-ethernet devices going to differnet networks that you're hotplugging) you can do determinations based on MAC/ESI address > Why is it the "correct interface number"? If I have two USB modems (say > interfaces 0 and 1) and I restart the hotplug subsystem, they will both > be disconnected and reconnected. Even with such an API as you suggest, > there is nothing to stop them being assigned interface numbers 1 and 0 > on reconnection. Is that wrong? No, if you specifically do something to trigger a rescan of the bus then you'd expect the order to possibly change, right? Again, no different than what happens with ethernet devices -Mitch ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
