From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261512AbTI3OKV (ORCPT ); Tue, 30 Sep 2003 10:10:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261514AbTI3OKV (ORCPT ); Tue, 30 Sep 2003 10:10:21 -0400 Received: from 81-2-122-30.bradfords.org.uk ([81.2.122.30]:46464 "EHLO 81-2-122-30.bradfords.org.uk") by vger.kernel.org with ESMTP id S261512AbTI3OKM (ORCPT ); Tue, 30 Sep 2003 10:10:12 -0400 Date: Tue, 30 Sep 2003 15:10:14 +0100 From: John Bradford Message-Id: <200309301410.h8UEAEgJ000652@81-2-122-30.bradfords.org.uk> To: Dave Jones Cc: Jamie Lokier , akpm@osdl.org, torvalds@osdl.org, linux-kernel@vger.kernel.org In-Reply-To: <20030930133113.GC23333@redhat.com> References: <200309300817.h8U8HGrf000881@81-2-122-30.bradfords.org.uk> <20030930133113.GC23333@redhat.com> Subject: Re: your mail Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Quote from Dave Jones : > On Tue, Sep 30, 2003 at 09:17:16AM +0100, John Bradford wrote: > > > Of course a kernel compiled strictly for 386s may seem to boot on an > > Athlon but not work properly. So what? Just don't run the 'wrong' > > kernel. > > Wrong answer. How do you intend to install Linux when a distro boot > kernel is compiled for lowest-common-denominator (386), and is the > 'wrong' kernel for an Athlon ? I don't. I *never* suggested doing that. I clearly said a kernel compiled *strictly* for 386s. I.E. Without support for other processors. > We hashed this argument out a week or so ago, it seems the message > didn't get across. YOU CAN NOT DISABLE ERRATA WORKAROUNDS IN A KERNEL > THAT MAY POSSIBLY BOOT ON HARDWARE THAT WORKAROUND IS FOR. It seems the message didn't get across to you. Have you actually looked at Adrian's patch? *Forget* that 386=lowest-common-denominator. This '386=lowest-common-denominator' theme is out of date, and we should be moving away from it - oh, hang on, that's exactly what Adrian's patch allows us to do. A distribution installation kernel needs to boot all supported hardware - of course it does. So what? Just select support for all the processors in the configurator. No, don't just select 386, because 386 doesn't mean 386 and above anymore with Adrian's patch, it means support 386 and don't bloat the kernel with workarounds for other processors. Select *all* processors. Now you have a nice, (bloated), kernel that boots on the same hardware that you old '386' one did. Fine for installation on diverse hardware. Rubbish for performance. Unless, of course, you object to the possibility that somebody might go out of their way to compile a 386 specific kernel from source themselves, then run it on an Athlon. By chance it will probably appear to work OK, but won't have the workaround enabled. So what? Only somebody who knows exactly what they were doing is likely to do that - how could it happen by accident? If you really must, put a warning in to say, 'This kernel doesn't support your processor', but doing that just adds more bloat. OK, so the bloat will be freed after boot, but it's still bloat on the boot device, which matters in some embedded systems. > clearer ? It's clear that you didn't read my original post, yes. John.