From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934269AbZLJMlI (ORCPT ); Thu, 10 Dec 2009 07:41:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758524AbZLJMlF (ORCPT ); Thu, 10 Dec 2009 07:41:05 -0500 Received: from nat.nue.novell.com ([195.135.221.3]:49903 "EHLO emea5-mh.id5.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757986AbZLJMlE (ORCPT ); Thu, 10 Dec 2009 07:41:04 -0500 X-Greylist: delayed 1202 seconds by postgrey-1.27 at vger.kernel.org; Thu, 10 Dec 2009 07:41:04 EST Message-ID: <4B20E7B2.1010208@suse.de> Date: Thu, 10 Dec 2009 15:21:06 +0300 From: Alexey Starikovskiy User-Agent: Thunderbird 2.0.0.23 (X11/20090817) MIME-Version: 1.0 To: Xiaotian Feng CC: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Len Brown , Bob Moore , Lin Ming , Pavel Machek Subject: Re: [PATCH -V2] acpi: don't cond_resched if irq is disabled References: <20091210100907.GA2446@ucw.cz> <1260446205-16868-1-git-send-email-dfeng@redhat.com> In-Reply-To: <1260446205-16868-1-git-send-email-dfeng@redhat.com> X-Enigmail-Version: 0.95.7 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 Hi Xiaotian, I think, this is another round of "armor vs. bullet" race... It will hold until might_sleep() logic changes again. Please consider using preemptible() -- IMHO this is the check we should perform in our case of voluntary preemption. Regards, Alex. Xiaotian Feng пишет: > commit 8bd108d adds preemption point after each opcode parse, then > a sleeping function called from invalid context bug was founded > during suspend/resume stage. this was fixed in commit abe1dfa by > don't cond_resched when irq_disabled. But recent commit 138d156 changes > the behaviour to don't cond_resched when in_atomic. This makes the > sleeping function called from invalid context bug happen again, which > is reported in http://lkml.org/lkml/2009/12/1/371. > > This patch also fixes http://bugzilla.kernel.org/show_bug.cgi?id=14483 > > Reported-and-bisected-by: Larry Finger > Reported-and-bisected-by: Justin P. Mattock > Signed-off-by: Xiaotian Feng > Cc: Len Brown > Cc: Bob Moore > Cc: Lin Ming > Cc: Alexey Starikovskiy > Cc: Pavel Machek > --- > include/acpi/platform/aclinux.h | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h > index 9d7febd..0946997 100644 > --- a/include/acpi/platform/aclinux.h > +++ b/include/acpi/platform/aclinux.h > @@ -152,7 +152,7 @@ static inline void *acpi_os_acquire_object(acpi_cache_t * cache) > #include > #define ACPI_PREEMPTION_POINT() \ > do { \ > - if (!in_atomic_preempt_off()) \ > + if (!in_atomic_preempt_off() && !irqs_disabled()) \ > cond_resched(); \ > } while (0) >