On Tue, Jun 08, 2021 at 09:50:01AM -0700, Jack Pham wrote: > Hi Peter, > > On Tue, Jun 08, 2021 at 06:56:56PM +0800, Peter Chen wrote: > > When do system reboot, it calls dwc3_shutdown and the whole debugfs > > for dwc3 has removed first, when the gadget tries to do deinit, and > > remove debugfs for its endpoints, it meets NULL pointer dereference > > issue when call debugfs_lookup. Fix it by removing the whole dwc3 > > debugfs later than dwc3_drd_exit. > > Ouch, thanks for catching this! I think in your previous reply[1] you > did warn about the debugfs_remove_recursive() getting called twice, but > it seems here the issue is due to the debugfs_lookup() getting called on > a stale dwc->root pointer after it was already removed. We can also fix this by getting rid of that "root" pointer as it's useless (we can look it up if we need it.) I'll send a patch later to do that, as it's a good idea to do anyway, and is independant of this fix. thanks, greg k-h
