On Fri, Aug 09, 2019 at 12:38:35PM +0000, Schmid, Carsten wrote: > Hi again, > > >> > >> Hey, i did not want to trigger an eartquake in the basement of the kernel ;-) > >> My intention was to prevent some crashes, and help developers to find their bugs. > >> I think my patch exactly does this. > > > > Hehe, actually drivers not being able to block unbind has been bugging me > > for > > a while now, because there are cases where this would be really helpful. > >>> 1) make resources refcounted, have child resources take a ref on the parent > >>> 2) Disallow unbind on devices with bound child-devices? > >>> > >> Exactly what i was thinking of in first attempts. > >> But i fear that would break even more use cases. > >> > >> Hans, directly regarding the driver: > >> The problem i see is that the xhci_intel_unregister_pdev which is added > >> as an action with devm_add_action_or_reset() is called late by the framework, > >> later than the usb_hcd_pci_remove() in xhci_pci_remove. > >> Is there any chance to trigger this before? > >> This is what Greg meant with "right order". > > > > Ah, I missed that part, sure that should be easy, just stop using > > devm_add_action_or_reset() and do the xhci_intel_unregister_pdev() > > manually at the right time. The downside of this is that you also > > need to make sure it happens at the right time from probe error-paths > > but given the bug you are hitting, I guess that is probably > > already a problem. > > > @Hans: > Sure, will have a look at this. I think i have found where to do that, > but need to check how to get the pdev pointer there .... > > @Greg: > I am still confident that my patch in __release_region should be taken in. Ok, submit it in a "real" way and we can consider it :) thanks, greg k-h
