From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: current git kernel has strange problems during bisect Date: Sun, 11 Jan 2009 12:04:12 -0800 (PST) Message-ID: References: <200901111602.53082.borntraeger@de.ibm.com> <200901111607.59054.borntraeger@de.ibm.com> <200901111620.03345.borntraeger@de.ibm.com> <20090111194258.GA4840@uranus.ravnborg.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Christian Borntraeger , Johannes Schindelin , git@vger.kernel.org, Linux Kernel Mailing List To: Sam Ravnborg X-From: git-owner@vger.kernel.org Sun Jan 11 21:06:10 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1LM6ZE-0005e9-MP for gcvg-git-2@gmane.org; Sun, 11 Jan 2009 21:05:53 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752151AbZAKUE3 (ORCPT ); Sun, 11 Jan 2009 15:04:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751880AbZAKUE2 (ORCPT ); Sun, 11 Jan 2009 15:04:28 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:34462 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905AbZAKUE1 (ORCPT ); Sun, 11 Jan 2009 15:04:27 -0500 Received: from imap1.linux-foundation.org (imap1.linux-foundation.org [140.211.169.55]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id n0BK4DGa015784 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 11 Jan 2009 12:04:14 -0800 Received: from localhost (localhost [127.0.0.1]) by imap1.linux-foundation.org (8.13.5.20060308/8.13.5/Debian-3ubuntu1.1) with ESMTP id n0BK4CPh032451; Sun, 11 Jan 2009 12:04:13 -0800 X-X-Sender: torvalds@localhost.localdomain In-Reply-To: <20090111194258.GA4840@uranus.ravnborg.org> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) X-Spam-Status: No, hits=-3.461 required=5 tests=AWL,BAYES_00 X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.13 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Sun, 11 Jan 2009, Sam Ravnborg wrote: > > The cost of moving this piece of history from one git tree to another > git tree is that we make it harder to debug the kernel for the advanced user > that knows how to do bisect. > > It is not like this history would be lost - one just had to look > somewhere else to find it. > > That may be a bad pain/benefit ratio - time will tell. Umm. No. Time is exactly what makes it useful. It will make all the downsides shrink, and the advantages stay. > There should be a way to avoid such pain when bisecting without > having to mark a semi-random (for the average person) commit as good. Well, you don't actually have to mark that semi-random one as good either. What you can do is to just mark anything that _only_ contains fs/btrfs as good. IOW, you don't have to know the magic number - you just have to be told that "oh, if you only have btrfs files, and you're not actively bisecting a btrfs bug, just do 'git bisect good' and continue". Yeah, you'll hit it a few times, but you don't even have to compile things or boot anything, so it's not actually going to be all that much slower than just knowing about the magic point either. So now you can consider yourself told how to solve it. It wasn't that hard. And the advantage is that we have real history. Linus