From owner-freebsd-current Thu Apr 4 12:49:35 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id MAA29412 for current-outgoing; Thu, 4 Apr 1996 12:49:35 -0800 (PST) Received: from GndRsh.aac.dev.com (GndRsh.aac.dev.com [198.145.92.241]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id MAA29380 for ; Thu, 4 Apr 1996 12:49:12 -0800 (PST) Received: (from rgrimes@localhost) by GndRsh.aac.dev.com (8.6.12/8.6.12) id MAA07188; Thu, 4 Apr 1996 12:43:29 -0800 From: "Rodney W. Grimes" Message-Id: <199604042043.MAA07188@GndRsh.aac.dev.com> Subject: Re: tty-level buffer overflows - what to do? To: nate@sri.MT.net (Nate Williams) Date: Thu, 4 Apr 1996 12:43:29 -0800 (PST) Cc: root@deadline.snafu.de, jgreco@brasil.moneng.mei.com, current@FreeBSD.org In-Reply-To: <199604041914.MAA17253@rocky.sri.MT.net> from Nate Williams at "Apr 4, 96 12:14:09 pm" X-Mailer: ELM [version 2.4ME+ PL11 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-current@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk > > But another problem is still going on on that machine. During boot there > > are several occurences of "stray irq 7" messages until syslog says it would > > not log them anymore. I have no idea where this stray irq's should happen. > > Physically there is no adaptor card installed which could ever generate a > > IRQ 7 ? Possible that this has to do with the other thing? > > This is a pretty good indication that something is mis-confugred. IRQ 7 > is the 'junk' interrupt, which means it gets all of the interrupts not > otherwise assigned to a particular piece of hardware. Something is > generating interrupts on your system bogusly and you need to find out > what. This is not quite correct, IRQ 7 is signal when someone asserts an IRQ singal then removes that signal _before_ the CPU runs the interrupt acknowledge cycle to the 8259 PIC. Devices that fully assert and hold it asserted do _not_ cause IRQ7, they cause there respective interrupt. Often the cause of stray IRQ7's is noisy or floating IRQ signals from boards that are not recognized by FreeBSD. In any case a system having this problem is going to be marginal at best, you should be able to see the rate of these events with a vmstat -i, watch the irq 7 counter... if you only get a burst of these during boot then you are probably okay and it is caused by some strange piece of hardware that is tickled into bad behavior by the invasive FreeBSD probe code, one way to cut that down is to eliminate all devices from the kernel that you do not really have. -- Rod Grimes rgrimes@gndrsh.aac.dev.com Accurate Automation Company Reliable computers for FreeBSD