Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753519AbbFOFvL (ORCPT ); Mon, 15 Jun 2015 01:51:11 -0400 Received: from smtprelay2.synopsys.com ([198.182.60.111]:39634 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752559AbbFOFvD convert rfc822-to-8bit (ORCPT ); Mon, 15 Jun 2015 01:51:03 -0400 From: Vineet Gupta To: Max Filippov , Alexey Brodkin CC: "linux-kernel@vger.kernel.org" Subject: Re: arc_pmu not initialized in the arc/kernel/perf_event.c? Thread-Topic: arc_pmu not initialized in the arc/kernel/perf_event.c? Thread-Index: AQHQpi4FF6MtWsVTW0q8xXlBPDMr3A== Date: Mon, 15 Jun 2015 05:50:59 +0000 Message-ID: References: <1434236946-15326-1-git-send-email-jcmvbkbc@gmail.com> Accept-Language: en-US, en-IN Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.12.197.3] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1940 Lines: 57 -CC Mischa (left Synopsys a while back) +CC Alexey (does most fo perf work these days) Hi Max, On Sunday 14 June 2015 04:39 AM, Max Filippov wrote: > Mischa, Vineet, > > Looking at ARC PMU driver I've got an impression that its static arc_pmu > is left uninitialized, which possibly leads to Oops once registered > callbacks are invoked. I don't have neither ARC toolchain nor hardware to > test it, so I may be missing something. Below is the fix for it. > > Thanks. > -- Max > > ---8<--- > From: Max Filippov > Subject: [PATCH] arc: fix use of uninitialized arc_pmu > > static arc_pmu in the arch/arc/kernel/perf_event.c is not initialized as > it's shadowed by a local variable of the same name in the > arc_pmu_device_probe. > > Signed-off-by: Max Filippov Thx for the fix. Indeed looks like a big SNAFU on my side. The reason we didn't run into this despite pretty regular use of perf is that we have been using a bunch of out of tree patches (recently floated for upstream) which removed the offending code for other reasons. Neverthless I will add this to for-next and CC stable as well. Thx, -Vineet > --- > arch/arc/kernel/perf_event.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c > index fd2ec50..57b58f5 100644 > --- a/arch/arc/kernel/perf_event.c > +++ b/arch/arc/kernel/perf_event.c > @@ -266,7 +266,6 @@ static int arc_pmu_add(struct perf_event *event, int flags) > > static int arc_pmu_device_probe(struct platform_device *pdev) > { > - struct arc_pmu *arc_pmu; > struct arc_reg_pct_build pct_bcr; > struct arc_reg_cc_build cc_bcr; > int i, j, ret; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/