Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758489Ab3EGP6r (ORCPT ); Tue, 7 May 2013 11:58:47 -0400 Received: from mail-la0-f44.google.com ([209.85.215.44]:54972 "EHLO mail-la0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758378Ab3EGP6p (ORCPT ); Tue, 7 May 2013 11:58:45 -0400 MIME-Version: 1.0 In-Reply-To: <5189234D.3040208@codeaurora.org> References: <1366974299-17877-1-git-send-email-pranavkumar@linaro.org> <87obcyc9sh.fsf@rustcorp.com.au> <336C59AA-D5D7-472E-A8DA-EEB413DD6C68@suse.de> <87sj27xxjr.fsf@rustcorp.com.au> <87ip2wr8tp.fsf@rustcorp.com.au> <87txmfo0rl.fsf@rustcorp.com.au> <5189234D.3040208@codeaurora.org> From: Peter Maydell Date: Tue, 7 May 2013 16:58:23 +0100 Message-ID: Subject: Re: [PATCH 0/2] Early printk support for virtio console devices. To: Christopher Covington Cc: Rusty Russell , "linaro-kernel@lists.linaro.org" , "patches@linaro.org" , "linux-kernel@vger.kernel.org List" , Alexander Graf , Amit Shah , "kvmarm@lists.cs.columbia.edu" , "linux-arm-kernel@lists.infradead.org" , Pranavkumar Sawargaonkar Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1169 Lines: 28 On 7 May 2013 16:52, Christopher Covington wrote: > On 05/07/2013 08:19 AM, Peter Maydell wrote: >> Well, at the moment EARLY_PRINTK is hardcoded to >> "use some specific UART or equivalent selected at >> compile time". So the equivalent presumably would >> be to hard-compile "use virtio-console", but then >> how does that code know where the virtio-console >> is in the address space? > > arm64 uses a kernel argument. This mixes up "information that the user provides to the kernel" (ie configuration) with "information that QEMU or kvmtool should provide to the kernel" (ie hardware description), and would require QEMU/kvmtool to parse the user's commandline tool to figure out if they needed to override it or edit it (or alternatively, would require the user to know internal details of QEMU/kvmtool's address map for the guest). I think it would be nicer to keep them separate. thanks -- PMM -- 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/