From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755016AbdL1RpF (ORCPT ); Thu, 28 Dec 2017 12:45:05 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:33157 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754390AbdL1RpB (ORCPT ); Thu, 28 Dec 2017 12:45:01 -0500 Date: Thu, 28 Dec 2017 18:44:56 +0100 (CET) From: Thomas Gleixner To: Andy Shevchenko cc: "alan@linux.intel.com" , "Ailus, Sakari" , "linux-kernel@vger.kernel.org" , "linux-media@vger.kernel.org" Subject: Re: IRQ behaivour has been changed from v4.14 to v4.15-rc1 In-Reply-To: <1514482448.7000.460.camel@linux.intel.com> Message-ID: References: <1514481444.7000.451.camel@intel.com> <1514482448.7000.460.camel@linux.intel.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 28 Dec 2017, Andy Shevchenko wrote: > On Thu, 2017-12-28 at 18:21 +0100, Thomas Gleixner wrote: > > > [ 85.167061] spurious APIC interrupt through vector ff on CPU#0, > > > should never happen. > > > [ 85.199886] atomisp-isp2 0000:00:03.0: stream[0] started. > > > > > > and Ctrl+C does NOT work. Machine just hangs. > > > > > > It might be related to this: > > > https://lkml.org/lkml/2017/12/22/697 > > > > I don't think so. > > > > Does the patch below cure it? > > Unfortunately, no. > > Same behaviour. > > Tell me if I need to provide some debug before it hangs. For now I have > apic=debug (AFAIR it doesn't affect this). The interesting question is why that spurious APIC interrupt through vector ff happens. Can you please add the following to the kernel command line: 'trace_events=irq_vectors:* ftrace_dump_on_oops' and apply the patch below. That should spill out the trace over serial (I hope you have that ...) Thanks, tglx 8<--------------- --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1978,6 +1978,8 @@ void __init register_lapic_address(unsig /* see sw-dev-man vol 3, chapter 7.4.13.5 */ pr_info("spurious APIC interrupt through vector %02x on CPU#%d, " "should never happen.\n", vector, smp_processor_id()); + tracing_off(); + BUG(); trace_spurious_apic_exit(vector); exiting_irq();