Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753806AbWLPVg5 (ORCPT ); Sat, 16 Dec 2006 16:36:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753808AbWLPVg5 (ORCPT ); Sat, 16 Dec 2006 16:36:57 -0500 Received: from smtp.osdl.org ([65.172.181.25]:46348 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753806AbWLPVg4 (ORCPT ); Sat, 16 Dec 2006 16:36:56 -0500 Date: Sat, 16 Dec 2006 13:36:28 -0800 (PST) From: Linus Torvalds To: Alistair John Strachan cc: Jens Axboe , Linux Kernel Mailing List , Jeff Garzik Subject: Re: Linux 2.6.20-rc1 In-Reply-To: <200612150141.09020.s0348365@sms.ed.ac.uk> Message-ID: References: <20061214212055.GR5010@kernel.dk> <200612150048.25552.s0348365@sms.ed.ac.uk> <200612150141.09020.s0348365@sms.ed.ac.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1574 Lines: 39 On Fri, 15 Dec 2006, Alistair John Strachan wrote: > > In total isolation, v2.6.19..0e75f9063f5c55fb0b0b546a7c356f8ec186825e it > breaks. Reverting just 0e75f9063f5c55fb0b0b546a7c356f8ec186825e, it works > again. > > So I think this is the source, but I can't explain why it "goes away" before > git1 and "comes back" before 2.6.20-rc1. Can you see if the kernel state at commit 77d172ce ("[PATCH] fix SG_IO bio leak") is good? Ie just do something like git checkout -b test-branch 77d172ce and compile and test that? That commit _should_ be the one that fixed whatever problems that commit 0e75f906 introduced. It *did* fix it for other - somewhat similar - situations. That said: Jens - I think 0e75f906 was a mistake. "blk_rq_unmap()" really should be passed the "struct bio", not the "struct request *". Right now it does something _really_ strange with requests with linked bio's, and I don't think your and FUJITA's "leak fix" really works. What happens when the bio was a linked list on the request, and you put the old _head_ on the request with "rq->bio = bio"? What happens to the other parts of it? IOW, I think this is broken. I think we should revert 0e75f906. Or at least you should explain to me why it's not broken, and why clearly people (eg Alistair) still see problems with it? Linus - 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/