Return-path: Received: from mail-lf0-f53.google.com ([209.85.215.53]:56188 "EHLO mail-lf0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753688AbdKGLNv (ORCPT ); Tue, 7 Nov 2017 06:13:51 -0500 Message-ID: <1510053227.24015.3.camel@gmail.com> (sfid-20171107_121542_814615_D21C0429) Subject: Re: Soft lockup in rt2x00usb_work_rxdone() From: Richard Genoud To: Stanislaw Gruszka Cc: Helmut Schaa , "linux-kernel@vger.kernel.org" , linux-wireless@vger.kernel.org Date: Tue, 07 Nov 2017 12:13:47 +0100 In-Reply-To: <20171107101320.GA12140@redhat.com> References: <1509983829.10974.2.camel@gmail.com> <20171107085327.GA11380@redhat.com> <20171107101320.GA12140@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: Le mardi 07 novembre 2017 à 11:13 +0100, Stanislaw Gruszka a écrit : > On Tue, Nov 07, 2017 at 11:06:39AM +0100, Richard Genoud wrote: > > > 3 short articles how to configure and use ftrace are here: > > > https://lwn.net/Articles/365835/ > > > https://lwn.net/Articles/366796/ > > > https://lwn.net/Articles/370423/ > > > > > > > I tried with ftrace, but I don't think there's a way to dump the > > trace > > when there's a soft lock-up > > (I can't do anything after the unbind, even the heartbeat led > > stopped blinking). > > I saw the /proc/sys/kernel/ftrace_dump_on_oops file, but there's no > > /proc/sys/kernel/ftrace_dump_on_soft_lock-up file :) > > You should configure function trace with rt2x* functions. After that > start tracing, unbind the device, then stop tracing and provide trace > output. Here is another trace, with rt2* as function filter. (sorry for the noise) Dumping ftrace buffer: --------------------------------- CPU:0 [LOST 3606923 EVENTS]  0)   0.000 us    |      } /* rt2x00usb_clear_entry */  0)   0.000 us    |    } /* rt2x00lib_rxdone */  0)   0.000 us    |    rt2x00queue_get_entry();  0)               |    rt2x00lib_rxdone() {  0)   0.000 us    |      rt2x00queue_index_inc();  0)               |      rt2x00usb_clear_entry() {  0)               |        rt2x00usb_kick_rx_entry() {  0)               |          rt2x00lib_dmastart() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)               |          rt2x00lib_dmadone() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)   0.000 us    |        }  0)   0.000 us    |      }  0)   0.000 us    |    }  0)   0.000 us    |    rt2x00queue_get_entry();  0)               |    rt2x00lib_rxdone() {  0)   0.000 us    |      rt2x00queue_index_inc();  0)               |      rt2x00usb_clear_entry() {  0)               |        rt2x00usb_kick_rx_entry() {  0)               |          rt2x00lib_dmastart() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)               |          rt2x00lib_dmadone() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)   0.000 us    |        }  0)   0.000 us    |      }  0)   0.000 us    |    }  0)   0.000 us    |    rt2x00queue_get_entry();  0)               |    rt2x00lib_rxdone() {  0)   0.000 us    |      rt2x00queue_index_inc();  0)               |      rt2x00usb_clear_entry() {  0)               |        rt2x00usb_kick_rx_entry() {  0)               |          rt2x00lib_dmastart() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)               |          rt2x00lib_dmadone() {  0)   0.000 us    |            rt2x00queue_index_inc();  0)   0.000 us    |          }  0)   0.000 us    |        }  0)   0.000 us    |      }  0)   0.000 us    |    } > > Thanks > Stanislaw