From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753129AbYIVNYR (ORCPT ); Mon, 22 Sep 2008 09:24:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751933AbYIVNYD (ORCPT ); Mon, 22 Sep 2008 09:24:03 -0400 Received: from qw-out-2122.google.com ([74.125.92.24]:38089 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752047AbYIVNYB (ORCPT ); Mon, 22 Sep 2008 09:24:01 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=IEqH+Sj41ENO2+BwISOOnBVoGfk+k1drtHkzKj3ld/KR5bQI/K9My5soyuZ2+duaXN mSlVNU9JkZ5u2r/A/FPyZFj619cFKysQBtB4ZsXlKFezOocKa69uL25bz6Nx+ECXlR9w iSUNPchxPAOI9xSBZlXUMbMUCDbOZP5CR5Yrg= Message-ID: <9e4733910809220623ka3670f7r8937d248fec4c986@mail.gmail.com> Date: Mon, 22 Sep 2008 09:23:59 -0400 From: "Jon Smirl" To: "Jeff Moyer" Subject: Re: netconsole and a serial one Cc: lkml , dhowells@redhat.com In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <9e4733910809211714j5d79592cj162f8be4ecebaa78@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 22, 2008 at 9:19 AM, Jeff Moyer wrote: > "Jon Smirl" writes: > >> I have both netconsole and a serial console setup on an embedded >> system. This is what I need for the boot process. >> >> After I'm booted I want to turn off printk() output to the serial >> console but keep it going to netconsole. >> I've been googling for an hour, how do I do this? >> >> I need to turn off the serial output after boot because serial >> printk() disables interrupts for up to 1ms which is enough to cause me >> to lose a lot of other interrupts. > > There's no way (that I know of) to do this presently. However, I think > David Howells has been working on a patch that reduces the amount of > time printk spends with IRQs disabled. I looked into interrupts and printk several years ago. If I recall correctly printk() prints with interrupts off to ensure stability in an OOPS situation. Could serial printk() be changed to disable interrupts only in the OOPS situation? It's all of the other non-critical printks that are impacting my system. -- Jon Smirl jonsmirl@gmail.com