Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268042AbUIKAOU (ORCPT ); Fri, 10 Sep 2004 20:14:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268043AbUIKAOT (ORCPT ); Fri, 10 Sep 2004 20:14:19 -0400 Received: from pollux.ds.pg.gda.pl ([153.19.208.7]:24336 "EHLO pollux.ds.pg.gda.pl") by vger.kernel.org with ESMTP id S268042AbUIKAOR (ORCPT ); Fri, 10 Sep 2004 20:14:17 -0400 Date: Sat, 11 Sep 2004 02:14:13 +0200 (CEST) From: "Maciej W. Rozycki" To: Chris Wedgwood Cc: LKML , Linus Torvalds Subject: Re: [PATCH] i386 reduce spurious interrupt noise In-Reply-To: <20040910231052.GA3078@taniwha.stupidest.org> Message-ID: References: <20040902192820.GA6427@taniwha.stupidest.org> <20040910231052.GA3078@taniwha.stupidest.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2147 Lines: 51 On Fri, 10 Sep 2004, Chris Wedgwood wrote: > > > - printk (KERN_INFO "APIC error on CPU%d: %02lx(%02lx)\n", > > > + printk (KERN_DEBUG "APIC error on CPU%d: %02lx(%02lx)\n", > > > This should probably be KERN_ERR even. This is a serious condition -- if > > you ever get such a message, then inter-APIC messages get corrupted and > > this affects system's stability. > > These messages are very common on many platforms, infrequent (once > very few days to twice a day at most in my observations) and seemingly > harmless. These are just as harmless as single-bit RAM errors with ECC working. In both cases you want the problem to be reported. > I agree that if you get *many* of these certainly that would indicate > there is a problem but I've not not heard a single instance of this > and if that is the case we need to deal with it differently. Please search list archives for lots of such reports. > > > - printk("spurious 8259A interrupt: IRQ%d.\n", irq); > > > + printk(KERN_DEBUG "spurious 8259A interrupt: IRQ%d.\n", irq); > > > You may ever get a single message per system boot from this line. > > Sometimes as boot, though often in my experience several minutes after > boot. And never again until you reboot. That's what I mean. > > It encourages to have a look at the ERR counter in /proc/interrupts > > to check for possible problems, though admittedly the suggestion > > isn't especially clear. > > I think in *both* cases we want to detect a largish (more than 1 ever > n seconds or so) number of these and then complain, not before and > even then not excessively so that we printk our-selves to death. I agree for the latter case. I won't mind the message going away either. For the former you only really want to rate-limit the report -- some people apparently want or need to run broken hardware and they'd probably appreciate limiting the output. Maciej - 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/