Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751542Ab1EaEFY (ORCPT ); Tue, 31 May 2011 00:05:24 -0400 Received: from linux-sh.org ([111.68.239.195]:52751 "EHLO linux-sh.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750762Ab1EaEFW (ORCPT ); Tue, 31 May 2011 00:05:22 -0400 Date: Tue, 31 May 2011 13:04:44 +0900 From: Paul Mundt To: Magnus Damm Cc: linux-kernel@vger.kernel.org, johnstul@us.ibm.com, linux-sh@vger.kernel.org Subject: Re: [PATCH] clocksource: sh_tmu: Runtime PM support Message-ID: <20110531040444.GA1745@linux-sh.org> References: <20110425134026.4249.13858.sendpatchset@t400s> <20110523083005.GA11986@linux-sh.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110523083005.GA11986@linux-sh.org> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1182 Lines: 30 On Mon, May 23, 2011 at 05:30:06PM +0900, Paul Mundt wrote: > On Mon, Apr 25, 2011 at 10:40:26PM +0900, Magnus Damm wrote: > > From: Magnus Damm > > > > Add Runtime PM support to the TMU driver. > > [snip] > > > > + /* wake up device and enable clock */ > > + pm_runtime_get_sync(&p->pdev->dev); > > ret = clk_enable(p->clk); > > if (ret) { > > dev_err(&p->pdev->dev, "cannot enable clock\n"); > > + pm_runtime_put_sync(&p->pdev->dev); > > return ret; > > } > > > At this point the spinlock hasn't been initialized yet, so any of the > pm_runtime calls are pretty much unsafe. We could manually test > pm_runtime_enabled() before any of the get/put_sync() calls, but that gets to > be a bit ugly. Note that I will be reverting these patches for -rc2 if no progress is made here. This is a fundamental ordering issue with regards to locking, and is completely bogus for every SMP platform we have. -- 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/