Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030286AbWJCKnz (ORCPT ); Tue, 3 Oct 2006 06:43:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030287AbWJCKnz (ORCPT ); Tue, 3 Oct 2006 06:43:55 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:60304 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1030286AbWJCKny (ORCPT ); Tue, 3 Oct 2006 06:43:54 -0400 Date: Tue, 3 Oct 2006 12:35:03 +0200 From: Ingo Molnar To: Andrew Morton Cc: Thomas Gleixner , LKML , Jim Gettys , John Stultz , David Woodhouse , Arjan van de Ven , Dave Jones Subject: [patch] clockevents: drivers for i386, fix #2 Message-ID: <20061003103503.GA6350@elte.hu> References: <20061001225720.115967000@cruncher.tec.linutronix.de> <20061002210053.16e5d23c.akpm@osdl.org> <20061003084729.GA24961@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061003084729.GA24961@elte.hu> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.8 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.5 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] -0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1520 Lines: 50 * Ingo Molnar wrote: > yeah, i suspect it works again if you disable: > > CONFIG_X86_UP_APIC=y > CONFIG_X86_UP_IOAPIC=y > CONFIG_X86_LOCAL_APIC=y > CONFIG_X86_IO_APIC=y > > as the slowdown has the feeling of a runaway lapic timer irq. > > from code review so far we can only see an udelay(10) difference in > the initialization sequence of the PIT - we'll send a fix for that but > i dont think that's the cause of the bug. the patch below fixes that particular bug. But ... the symptoms you are describing have the feeling of being apic related. Ingo --------------------> Subject: clockevents: drivers for i386, fix #2 From: Ingo Molnar add back a mistakenly removed udelay(10) to the PIT initialization sequence. Signed-off-by: Ingo Molnar --- arch/i386/kernel/i8253.c | 1 + 1 file changed, 1 insertion(+) Index: linux/arch/i386/kernel/i8253.c =================================================================== --- linux.orig/arch/i386/kernel/i8253.c +++ linux/arch/i386/kernel/i8253.c @@ -45,6 +45,7 @@ static void init_pit_timer(enum clock_ev outb_p(0x34, PIT_MODE); udelay(10); outb_p(LATCH & 0xff , PIT_CH0); /* LSB */ + udelay(10); outb(LATCH >> 8 , PIT_CH0); /* MSB */ break; - 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/