From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] OMAP2+: clocksource: fix crash on boot when !CONFIG_OMAP_32K_TIMER Date: Thu, 24 Feb 2011 13:13:29 -0800 Message-ID: <20110224211328.GK20560@atomide.com> References: <20110224202157.GG20560@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:13399 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755511Ab1BXVNd (ORCPT ); Thu, 24 Feb 2011 16:13:33 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Paul Walmsley Cc: linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org * Paul Walmsley [110224 12:29]: > On Thu, 24 Feb 2011, Tony Lindgren wrote: > > > * Paul Walmsley [110222 18:58]: > > > > > > OMAP2+ kernels built without CONFIG_OMAP_32K_TIMER crash on boot after the > > > 2.6.38 sched_clock changes: > > > > > > [ 0.000000] OMAP clockevent source: GPTIMER1 at 13000000 Hz > > > [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00000000 > > > [ 0.000000] pgd = c0004000 > > > [ 0.000000] [00000000] *pgd=00000000 > > > [ 0.000000] Internal error: Oops: 80000005 [#1] SMP > > > [ 0.000000] last sysfs file: > > > [ 0.000000] Modules linked in: > > > [ 0.000000] CPU: 0 Not tainted (2.6.38-rc5-00057-g04aa67d #152) > > > [ 0.000000] PC is at 0x0 > > > [ 0.000000] LR is at sched_clock_poll+0x2c/0x3c > > > > > > Without CONFIG_OMAP_32K_TIMER, the kernel has an clockevent and > > > clocksource resolution about three orders of magnitude higher than > > > with CONFIG_OMAP_32K_TIMER set. The tradeoff is that the lowest > > > power consumption states are not available. > > > > > > Fix by calling init_sched_clock() from the GPTIMER clocksource init code. > > > > I'll queue this as a fix as it's a regression. > > Sounds good, I've got one or two other -rc candidates. Want me to build a > branch with this and the other two? Well I already applied this one. But for the two others yes please. Tony