From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932725AbbJMRoR (ORCPT ); Tue, 13 Oct 2015 13:44:17 -0400 Received: from mail.kernel.org ([198.145.29.136]:53840 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932562AbbJMRoQ (ORCPT ); Tue, 13 Oct 2015 13:44:16 -0400 MIME-Version: 1.0 In-Reply-To: <20151013115011.GA6546@infradead.org> References: <1439363241-31772-1-git-send-email-mlin@kernel.org> <1439363241-31772-6-git-send-email-mlin@kernel.org> <20151013115011.GA6546@infradead.org> Date: Tue, 13 Oct 2015 10:44:11 -0700 Message-ID: Subject: Re: [PATCH v6 05/11] block: remove split code in blkdev_issue_{discard,write_same} From: Ming Lin To: Christoph Hellwig Cc: lkml , Jens Axboe , Kent Overstreet , Dongsu Park , Mike Snitzer , "Martin K. Petersen" , Ming Lin , linux-nvme@lists.infradead.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 13, 2015 at 4:50 AM, Christoph Hellwig wrote: > On Wed, Aug 12, 2015 at 12:07:15AM -0700, Ming Lin wrote: >> From: Ming Lin >> >> The split code in blkdev_issue_{discard,write_same} can go away >> now that any driver that cares does the split. We have to make >> sure bio size doesn't overflow. >> >> For discard, we set max discard sectors to (1<<31)>>9 to ensure >> it doesn't overflow bi_size and hopefully it is of the proper >> granularity as long as the granularity is a power of two. > > This ends up breaking discard on NVMe devices for a me. An mkfs.xfs > which does a discard of the whole device now hangs the system. > Something in here makes it send discard command that the device doesn't > like and the aborts don't seem to help either, although that might be > an issue with the abort handling in the driver. > > Just a heads up for now, once I get a bit more time I'll try to collect > a blktrace to figure out how the commands sent to the driver look > different before and after the patch. I just did a quick test with a Samsung 900G NVMe device. mkfs.xfs is OK on 4.3-rc5. What's your device model? I may find a similar one to try.