Hi Mathias, On Thu, Jul 19, 2018 at 01:59:01PM +0300, Mathias Nyman wrote: > On 17.07.2018 18:10, Sudip Mukherjee wrote: > > Hi Alan, Greg, > > > > On Tue, Jul 17, 2018 at 03:49:18PM +0100, Sudip Mukherjee wrote: > > > On Tue, Jul 17, 2018 at 03:40:22PM +0100, Sudip Mukherjee wrote: > > > > Hi Alan, > > > > > > > > On Tue, Jul 17, 2018 at 10:28:14AM -0400, Alan Stern wrote: > > > > > On Tue, 17 Jul 2018, Sudip Mukherjee wrote: > > > > > > > > > > > I did some more debugging. Tested with a KASAN enabled kernel and that > > > > > > shows the problem. The report is attached. > > > > > > <snip> > > > > And, my hacky patch worked as I prevented it from calling > > usb_disable_interface() in this particular case. > > > > Back for a few days, looking at this I hope you had a good holiday. :) > > xhci driver will set up all the endpoints for the new altsetting already in > usb_hcd_alloc_bandwidth(). > <snip> > > As first aid I could try to implement checks that make sure the flushed URBs > trb pointers really are on the current endpoint ring, and also add some warning > if we are we are dropping endpoints with URBs still queued. Yes, please. I think your first-aid will be a much better option than the hacky patch I am using atm. > > But we need to fix this properly as well. > xhci needs to be more in sync with usb core in usb_set_interface(), currently xhci > has the altssetting up and running when usb core hasn't event started flushing endpoints. I am able to reproduce this on almost all cycles, so I can always test the fix for you after you are fully back from your holiday. -- Regards Sudip -- 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
