Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754705Ab2JHS7O (ORCPT ); Mon, 8 Oct 2012 14:59:14 -0400 Received: from mail-vc0-f174.google.com ([209.85.220.174]:46830 "EHLO mail-vc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752644Ab2JHS7K (ORCPT ); Mon, 8 Oct 2012 14:59:10 -0400 MIME-Version: 1.0 In-Reply-To: <20121007191627.GA19278@redhat.com> References: <20121006204736.GA1830@ds20.borg.net> <20121007165534.GA8024@redhat.com> <20121007171300.GA10942@redhat.com> <20121007180420.GA900@ds20.borg.net> <20121007191627.GA19278@redhat.com> Date: Mon, 8 Oct 2012 20:59:10 +0200 X-Google-Sender-Auth: 01UjCNg3KuAlXwWLxO6rBRaij-o Message-ID: Subject: Re: [regression] boot failure on alpha, bisected From: Geert Uytterhoeven To: Oleg Nesterov Cc: dl8bcu@dl8bcu.de, peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , Al Viro Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1841 Lines: 45 On Sun, Oct 7, 2012 at 9:16 PM, Oleg Nesterov wrote: > On 10/07, Thorsten Kranzkowski wrote: >> On Sun, Oct 07, 2012 at 07:13:00PM +0200, Oleg Nesterov wrote: >> > On 10/07, Oleg Nesterov wrote: >> > > Hmm. I know nothing about arch/alpha and I can't understand its entry.S. >> > > But _it seems_ to me that do_notify_resume() is called with irqs disabled. >> > > If this is true, then imho arch/alpha should be fixed. >> > > >> > > Before this commit task_work_run() enabled irqs, but this was the "side >> > > effect" of spin_lock_irq/spin_unlock_irq, we should not rely on this. >> > >> > Could you please test the debugging patch below? >> >> Of course. With that patch applied the kernel (ac3d0da) boots again. The trace line >> is printed about once a second, with values '2' and '4'. > > Thanks a lot Thorsten! > > So I'll probably send the patch which enables interrupts in > task_work_run(). I guess this needs "if (irqs_disabled())" > for lockdep. > > The question is, should I add the warning to remind that this > arch needs a fix? Just wondering. As this is on an SMP system, perhaps the read_barrier_depends() vs. smp_read_barrier_depends() matters here? http://lkml.indiana.edu/hypermail/linux/kernel/1209.3/00555.html Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- 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/