Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761786AbXEPER7 (ORCPT ); Wed, 16 May 2007 00:17:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754682AbXEPERw (ORCPT ); Wed, 16 May 2007 00:17:52 -0400 Received: from wr-out-0506.google.com ([64.233.184.227]:22965 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754665AbXEPERv (ORCPT ); Wed, 16 May 2007 00:17:51 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=m6imSZI1mVOW2aSW++Sumk9AFnGD9tHD3OaiZDu254KhDuyNBQusoBinWwBo0wif/qpQiRBcyjWsfv1jKch5QMIms7c+qf55KTyHlcn6oFcO1olFoDmnTRWxJeE4hFfW/zA9dP6Uo6QApi12mKhFeXRipc++yvPym0sTbx5nqwc= Message-ID: <86802c440705152117o34325f1dw4a0cdf95241b3b42@mail.gmail.com> Date: Tue, 15 May 2007 21:17:50 -0700 From: "Yinghai Lu" To: "Gerd Hoffmann" , "Andi Kleen" , "Bjorn Helgaas" , akpm@linux-foundation.org, "Linus Torvalds" , "Eric W. Biederman" Subject: Re: [patch] early printk and boot console fixups. Cc: "linux kernel mailing list" In-Reply-To: <45D5C473.4010608@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <45D5C473.4010608@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1917 Lines: 43 On 2/16/07, Gerd Hoffmann wrote: > The console subsystem already has an idea of a boot console, using the > CON_BOOT flag. The implementation has some flaws though. The major > problem is that presence of a boot console makes register_console() > ignore any other console devices (unless explicitly specified on the > kernel command line). > > This patch fixes the console selection code to *not* consider a boot > console a full-featured one, so the first "normal" console registering > will become the default boot console instead. This way the unregister > call for the boot console in register_console() actually triggers and > the handover from the boot console to the real console device works > smoothly. > > The patch also changes the x86 early_printk code to use this. The early > console is simply tagged as boot console, the disable_early_printk() > call is gone as it isn't needed any more. just notice console handover patch got into mainline 5/8. for early_uart_console, I have some ideas: 1. merged that into early_serial_console in arch/x86_64/kernel/early_printk.c, and move early_printk.c to kernel/, --- make it understand earlyprintk=uart,io,0x3f8,9600n8 earlyprintk=uart,mmio,0xff5e0000,115200n8 in addition to vga, ttyS, serial 2. or make early_uart_console to be another CON_BOOT, and get rid of late_initcall(early_uart_console_switch). actually with late_initcall early_uart_console_switch instead of console handover, we will lose char output from serial drv init to late_initcall stage. in this case, we need to EARLY_SERIAL_CONSOLE to select early_serial_console or early_uart_console for x86_64 platform. YH - 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/