On Wed, 9 Mar 2011, Sarah Sharp wrote: > > This is okay as it stands, but I wonder if it can be simplified. The > > order in which the hcd structures are released doesn't matter, because > > the bandwidth mutex won't be accessed after the root hubs are > > unregistered. Hence the mutex can be deallocated when the primary hcd > > is removed (since the primary hcd structure always has to be removed > > last). > > > > Or am I missing something? > > No, you're not missing something, and I think your suggestion simplifies > things a lot. > > The hcd->primary_hcd is set when usb_create_shared_hcd() is called, but > looking through the code, it's never cleared when the primary_hcd is > freed. It would be useful to use that fact when testing for the > primary_hcd in hcd_release(), but I wonder if it will lead to bad > pointer dereferences later... Well, the idea is simple enough.: Always deallocate the bandwidth_mutex except when you're removing a secondary shared hcd. That should work out okay, regardless of how you manage the pointers. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
