From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752273AbaABUDI (ORCPT ); Thu, 2 Jan 2014 15:03:08 -0500 Received: from mail-pb0-f48.google.com ([209.85.160.48]:47522 "EHLO mail-pb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751172AbaABUDG (ORCPT ); Thu, 2 Jan 2014 15:03:06 -0500 Message-ID: <52C5C5F6.70803@linaro.org> Date: Thu, 02 Jan 2014 12:03:02 -0800 From: John Stultz User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Linus Torvalds , =?UTF-8?B?S3J6eXN6dG9m?= =?UTF-8?B?IEhhxYJhc2E=?= CC: =?UTF-8?B?VXdlIEtsZWluZS1Lw7ZuaWc=?= , Willy Tarreau , lkml , "linux-arm-kernel@lists.infradead.org" , Ingo Molnar , Stephen Boyd Subject: Re: v3.13-rc6+ regression (ARM board) References: <20131231104511.GA9688@1wt.eu> <20140102101455.GG10158@pengutronix.de> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/02/2014 11:38 AM, Linus Torvalds wrote: > On Thu, Jan 2, 2014 at 4:07 AM, Krzysztof Hałasa wrote: >> This means these two commits don't like each other: >> >> seqcount: Add lockdep functionality to seqcount/seqlock structures >> sched_clock: Use seqcount instead of rolling our own > Does something like this fix it for you? > > --- a/kernel/time/sched_clock.c > +++ b/kernel/time/sched_clock.c > @@ -36,6 +36,7 @@ core_param(irqtime, irqtime, int, 0400); > > static struct clock_data cd = { > .mult = NSEC_PER_SEC / HZ, > + .seq = SEQCNT_ZERO(cd.seq), > }; > > static u64 __read_mostly sched_clock_mask; > > (The above is not even compile-tested, because x86 doesn't use > GENERIC_SCHED_CLOCK. So I did the patch blindly, but I think you get > the idea..) Sheesh. Just finishing up holiday email backlog and Linus already has a fix. :) This looks like it should fix the issue, and does build for me. Assuming it works for Krzysztof, Acked-by: John Stultz I'll do another grep pass through -rc6 to make sure no other new uninitialized seqlock usage was added. thanks -john From mboxrd@z Thu Jan 1 00:00:00 1970 From: john.stultz@linaro.org (John Stultz) Date: Thu, 02 Jan 2014 12:03:02 -0800 Subject: v3.13-rc6+ regression (ARM board) In-Reply-To: References: <20131231104511.GA9688@1wt.eu> <20140102101455.GG10158@pengutronix.de> Message-ID: <52C5C5F6.70803@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 01/02/2014 11:38 AM, Linus Torvalds wrote: > On Thu, Jan 2, 2014 at 4:07 AM, Krzysztof Ha?asa wrote: >> This means these two commits don't like each other: >> >> seqcount: Add lockdep functionality to seqcount/seqlock structures >> sched_clock: Use seqcount instead of rolling our own > Does something like this fix it for you? > > --- a/kernel/time/sched_clock.c > +++ b/kernel/time/sched_clock.c > @@ -36,6 +36,7 @@ core_param(irqtime, irqtime, int, 0400); > > static struct clock_data cd = { > .mult = NSEC_PER_SEC / HZ, > + .seq = SEQCNT_ZERO(cd.seq), > }; > > static u64 __read_mostly sched_clock_mask; > > (The above is not even compile-tested, because x86 doesn't use > GENERIC_SCHED_CLOCK. So I did the patch blindly, but I think you get > the idea..) Sheesh. Just finishing up holiday email backlog and Linus already has a fix. :) This looks like it should fix the issue, and does build for me. Assuming it works for Krzysztof, Acked-by: John Stultz I'll do another grep pass through -rc6 to make sure no other new uninitialized seqlock usage was added. thanks -john