From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751047AbeBJDOw (ORCPT ); Fri, 9 Feb 2018 22:14:52 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:52278 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbeBJDOv (ORCPT ); Fri, 9 Feb 2018 22:14:51 -0500 Subject: Re: [PATCH V2 0/6]nvme-pci: fixes on nvme_timeout and nvme_dev_disable To: Keith Busch Cc: axboe@fb.com, hch@lst.de, linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Sagi Grimberg References: <1517822415-11710-1-git-send-email-jianchao.w.wang@oracle.com> <073ce416-fd26-b41a-187d-1db9210c48b0@grimberg.me> <20180208175606.GD5039@localhost.localdomain> <20180209171231.GB6970@localhost.localdomain> From: "jianchao.wang" Message-ID: <1aa130e6-a1ff-bd17-a141-1a52f596dd8b@oracle.com> Date: Sat, 10 Feb 2018 10:59:32 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8800 signatures=668666 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=962 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1802100039 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Keith On 02/10/2018 10:32 AM, jianchao.wang wrote: > Hi Keith > > Thanks for your kindly response here. > That's really appreciated. > > On 02/10/2018 01:12 AM, Keith Busch wrote: >> On Fri, Feb 09, 2018 at 09:50:58AM +0800, jianchao.wang wrote: >>> >>> if we set NVME_REQ_CANCELLED and return BLK_EH_HANDLED as the RESETTING case, >>> nvme_reset_work will hang forever, because no one could complete the entered requests. >> >> Except it's no longer in the "RESETTING" case since you added the >> "CONNECTING" state, so that's already broken for other reasons... >> > > Yes, but as your patch, we have to fail the IOs and even kill the controller. > In fact, up to nvme_wait_freeze in nvme_reset_work, the RECONNECTING state has been completed. > We even could say it is in LIVE state. Maybe we should recover the controller again instead > of fail the IOs and kill the controller. > > On the other hand, can you share with me why we cannot use blk_set_preempt_only to replace > blk_freeze_queue ? we just want to gate the new bios out of generic_make_request and we > needn't use the preempt requests. > > Looking forward your advice and directive. Avoid wait_freeze in nvme_reset_work should be a better way to fix this defect. > > Thanks > Jianchao