Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932667AbaGET0n (ORCPT ); Sat, 5 Jul 2014 15:26:43 -0400 Received: from gw-1.arm.linux.org.uk ([78.32.30.217]:55486 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756136AbaGET0m (ORCPT ); Sat, 5 Jul 2014 15:26:42 -0400 Date: Sat, 5 Jul 2014 20:26:34 +0100 From: Russell King - ARM Linux To: pawandeep oza Cc: akpm@linux-foundation.org, holt@sgi.com, mingo@kernel.org, sboyd@codeaurora.org, k.khlebnikov@samsung.com, u.kleine-koenig@pengutronix.de, Nicolas Pitre , linux-arm-kernel@lists.infradead.or, linux-kernel@vger.kernel.org Subject: Re: [PATCH] machine_power_off: not only local_irq_disable but also do disable preemption Message-ID: <20140705192634.GT21766@n2100.arm.linux.org.uk> References: <20140705181015.GQ21766@n2100.arm.linux.org.uk> <20140705190105.GR21766@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 06, 2014 at 12:34:14AM +0530, pawandeep oza wrote: > no this is not a generic code bug, because only in this scenerio, problem > might happen. > because other core is plugged out and now there is no chance that it can > release the spin_lock it would have held previously. > > so this core must run with preemption and interrupt disabled. > > this is only applicable for shutdown, not for any other scenerio. No. See my reply I just sent. Preempting when local interrupts disabled is a bug. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. -- 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/