On 06-02-25 12:59 am, Pelle Windestam wrote: >>>>>> Odd, you have a usb-serial gadget device in this system that is >>>>>> disconnecting somehow? That oops doesn't point to anything in the >>>>>> usb gadget codebase, "all" we have done is move the call to >>>>>> shutdown the endpoints to earlier in the disconnect function. >>>>> >>>>> Yes the board starts usb-serial and usb-ethernet gadget and on >>>>> reboot when tearing it down I am seeing the above. As soon as it >>>>> disables the tegra-xudc endpoints (as seen above) the board appears to >>> stall. >>>>> >>>>>> I'm glad to revert this, but it feels really odd that this is >>>>>> causing you an rcu stall issue. >>>>> >>>>> Thanks. I can't say I understand it either, but I am certain it is >>>>> caused by this change. >>>>> > > I do not have much to add in terms of solutions but want to chime in > that the same issue happened to me the other day when I upgraded my > kernel. It manifests itself with the rcu stall whenever I try to reboot > my device with the USB-cable connected (it is a usb-serial gadget > device). Moving the usb_ep_disable() calls to outside the lock (where > they were before the patch) solves it. Are you also using tegra-xudc ? ep_disable routine may be called in an atomic (interrupt) context. Regards, Prashanth K
