On Thu, 17 Mar 2005 11:42:00 -0800, David Brownell <[EMAIL PROTECTED]> wrote: > On Thursday 17 March 2005 11:24 am, Dmitry Torokhov wrote: > > On Thu, 17 Mar 2005 11:02:58 -0800, David Brownell <[EMAIL PROTECTED]> > > wrote: > > > On Thursday 17 March 2005 1:54 am, Brian Murphy wrote: > > > > Executive summary: > > > > loop until dependant device list is empty instead of for loop over > > > > changing list. > > > > > > In various other cases I've found that list_for_each_safe() is > > > actually not safe, and so I've had to switch to that same sort > > > of while-not-empty idiom. > > > > > > This makes me wonder about either compiler issues or basic > > > semantic issues with the definition of "safe" ... I leaned > > > towards thinking that "safe" was a misnomer, probably just > > > shorthand for "safe_except_for_what_you_really_want". > > > > > > > Well, as far as "list_*_safe" macros go they are actually "safe as far > > as deleting an element from the list in the middle of the loop by the > > same thread of execution", no more, no less. > > That's what I'd been trying to do when it misbehaved for me. > And what I understand Brian was doing, too.
Oh, yes... change that to "... deleting current element ...". After all list_*_safe only prefetches pointer to the next element in case memory occupied by the current element gets freed in the middle of the loop. I have re-read the tread and it looks like the problem is that device_release_driver is called recursively for the same bus which is not allowed (that limitation that hurts everyone). As far as I understand, for now caller has to disconnect/destroy all children before unregistering parent. I am doing pretty much the same with serio - when driver is unregistered I scan list of ports and unbind them from this driver. And every time I unbind a port I have to restart scanning the list because I might have deleted some children ports in the process. -- Dmitry ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&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
