From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756556AbZELR1Y (ORCPT ); Tue, 12 May 2009 13:27:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752781AbZELR1P (ORCPT ); Tue, 12 May 2009 13:27:15 -0400 Received: from fg-out-1718.google.com ([72.14.220.153]:16720 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752395AbZELR1O (ORCPT ); Tue, 12 May 2009 13:27:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=XErzuoHWnvhLUIyDcHOpU2dlRij/m98curzUTtlWRYwpKCIVVOMTC22yXcfdRIuL5u jFTvsMpzeQMmLMIqbYcStyE6M1z8nbJ0KgrqRHuNG9Ls3si7+HB0ba6q/a6874eZLDGO MQHqPof36+xT8X5CMjoNUu+fAQMptpx4yAaWE= Date: Tue, 12 May 2009 21:27:10 +0400 From: Cyrill Gorcunov To: Yinghai Lu Cc: Ingo Molnar , mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, eswierk@aristanetworks.com, linux-tip-commits@vger.kernel.org Subject: Re: [tip:irq/numa] x86: read apic ID in the !acpi_lapic case Message-ID: <20090512172710.GD12820@lenovo> References: <49FC85A9.2070702@kernel.org> <20090512112205.GA12108@elte.hu> <20090512145128.GA10220@lenovo> <20090512145808.GA20587@elte.hu> <4A099013.6040708@kernel.org> <20090512150631.GA32067@elte.hu> <20090512164617.GA21673@elte.hu> <20090512170246.GB12820@lenovo> <4A09ADE5.3010102@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A09ADE5.3010102@kernel.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [Yinghai Lu - Tue, May 12, 2009 at 10:12:05AM -0700] | Cyrill Gorcunov wrote: | > [Ingo Molnar - Tue, May 12, 2009 at 06:46:17PM +0200] | > | | > | got this on a testbox: | > | | > | [ 0.113333] WARNING: at arch/x86/kernel/apic/apic.c:253 warn_slowpath_null+0x28/0x50() | > | | > | Ingo | > | | > | > It's expected (unfortunately). If we have SMP compiled kernel | > we still rely on apic_read heavily. Since for fake'ed apic | > we just return 0 for any reading I suspect we could just drop | > WARN_ON_ONCE for native_apic_read_dummy. Yinghai? | > | > (well, actually we should clean up callees but it would require | > some effort) | | 32bit seems doesn't have this warning. | | and on 64bit, we always assumed have local APIC there. so could be that | noapic is not cleanly enforced | yes, that is why I said that we need to cleanup the call-pathes. And since it requires some effort we either could save WARN_ON_ONCE here (so it hit us everyday provoking to do cleanup) and keep in mind that it's expected behaviour at moment, or if it's that annoying -- remove it (though it would be just a hidding of code defect I think). Unfortunatelly I have a number of tasks to be done before I could start such a checking/cleanups. | | YH | -- Cyrill