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Fri, 2 Oct 2026 11:52:43 +0000 (GMT) Received: from [9.61.28.159] (unknown [9.61.28.159]) by smtpav01.dal12v.mail.ibm.com (Postfix) with ESMTP; Fri, 2 Oct 2026 11:52:43 +0000 (GMT) Message-ID: <573b1136-7fb1-4457-b5a9-9ee07e0c07ce@linux.ibm.com> Date: Fri, 2 Oct 2026 17:22:42 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 2/2] nvme-multipath: add fail_if_no_path sysfs attribute To: Krishna Iyer , Hannes Reinecke Cc: Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, saravanand@crusoe.ai, sjpark@crusoe.ai References: <20261001094857.74567-1-kiyer@crusoe.ai> <20261001094857.74567-3-kiyer@crusoe.ai> <4a4e228f-7143-4d5a-b773-2c6238852503@suse.de> <20261002105612.25298-1-kiyer@crusoe.ai> Content-Language: en-US From: Nilay Shroff In-Reply-To: <20261002105612.25298-1-kiyer@crusoe.ai> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Spam-Info: AW1haW4tMjYxMDAyMDA0NiBTYWx0ZWRfX0Cv7lmH5ABdC XMGDFqIChG9ty6CiRIJEOzlw21UpkKz14egmYEOO6AThUVMlA+m+mIF8l4P38rCgJN40Xu4BVbH mgg5U0MS7YcFE8QE2Y5m9ibmdrw230A= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYxMDAyMDA0NiBTYWx0ZWRfX+q5xhCOUv0O7 V7wZgisEZoY3EJhnoumb8SmM8raQPfEFa6M3evCEYiJF2kxf+BbT/qV0URCUXzJCNreeYtv79b0 Ehes1eL821wai+8l+t8NEs+NOVBC69RqI3i1cT8+4be9iCvbZe9EYnsDmYxbzm6OaT3D+IbkxQM hPkv38mSTCZFlvCc79SuOr64yLV+iYyXyc+UcGQOul11UXuybol95n71JmUPNkWSErzG8EkXhDD i6Dhi/PbT/lsVN9Sm3rde21gdYSxb07SIhltJlvcPPO3VBK1F0FrQlF22EAyUUZ2R/flOelV20Q boVUDlN+f4cisMyejBhwTFUyoz/DvR7d0JECtWr8JSZVciitm4I++Wk110ksRupA18mHb4FDUHR m8jOB9RVS8S16TRpxjDHG0K/6ArGoLycVYY+w0Ko++G/8dANLY0YJ1RqSrnUuGXcP50ZCsi5SON 0TRLwcEuf/8vWmnBSsQ== X-Proofpoint-GUID: mAPZQsDCx287cqa2V_-IhvhI110W83eQ X-Authority-Analysis: v=2.4 cv=RKcmjIi+ c=1 sm=1 tr=0 ts=6abf9b10 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=660iZSQnnn4A:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=0gLi0y45t31yEeiaKmAA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: mAPZQsDCx287cqa2V_-IhvhI110W83eQ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-10-02_03,2026-10-01_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 priorityscore=1501 spamscore=0 bulkscore=0 impostorscore=0 adultscore=0 lowpriorityscore=0 suspectscore=0 malwarescore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2609040000 definitions=main-2610020046 On 10/2/26 4:26 PM, Krishna Iyer wrote: > On 10/2/26 11:39 AM, Hannes Reinecke wrote: >> I do get the problem, but I think that 'fail_if_no_path' is a misnomer. >> Problem is that we already have a 'QUEUE_IF_NO_PATH' setting, so >> 'FAIL_IF_NO_PATH' really sounds like the inverstion of that. >> Only that it isn't. >> Maybe rename to 'FAIL_ON_CTRL_LOSS' to make it clear that the two >> settings really describe different use-cases? > > Agreed, and thanks. You are right that fail_if_no_path reads as the > inverse of queue_if_no_path when it is not, and the v4 split makes that > clearer. Patch 1 now fails the cases where a path exists but cannot > serve I/O, so the only thing this attribute still does is stop waiting > for a controller that is gone or reconnecting. I am happy to rename it, > and fail_on_ctrl_loss describes that well. > > One piece of history worth surfacing first. The fail_if_no_path name was > Nilay's suggestion in v2, so I would request we settle on one name you > both agree on rather than change it twice. Nilay, does fail_on_ctrl_loss > work for you? > Yes, I also like fail_on_ctrl_loss as Hannes suggested. The earlier fail_if_no_path name came from the dm-multipath policy, which uses the same name for a similar use case. However, I agree that fail_if_no_path could be misleading here since it sounds like the inverse of QUEUE_IF_NO_PATH. So I'd vote for fail_on_ctrl_loss for this change. Thanks, --Nilay