Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752573AbcCLItt (ORCPT ); Sat, 12 Mar 2016 03:49:49 -0500 Received: from mail-yw0-f181.google.com ([209.85.161.181]:35799 "EHLO mail-yw0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750702AbcCLItm (ORCPT ); Sat, 12 Mar 2016 03:49:42 -0500 MIME-Version: 1.0 In-Reply-To: <20160312074329.GA19066@kmo-pixel> References: <20160312074329.GA19066@kmo-pixel> Date: Sat, 12 Mar 2016 16:49:41 +0800 Message-ID: Subject: Re: e827091cb1 "block: merge: get the 1st and last bvec via helpers" broken From: Ming Lei To: Kent Overstreet Cc: Ming Lin , Jens Axboe , Linux Kernel Mailing List 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: 486 Lines: 15 On Sat, Mar 12, 2016 at 3:43 PM, Kent Overstreet wrote: > I don't know exactly how it's broken, but with that patch segment counting is > broken - I'm seeing blk_rq_map_sg() overrun the end of the sgtable. > > I suggest reverting it for 4.5... Kent, could you share your test case? I'd like to figure out the root cause. BTW, I don't object to revert it given it is close to v4.5 release, but I am curious how it breaks segment couting. Thanks, Ming Lei