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Fri, 27 Feb 2026 15:57:28 +0000 (GMT) Message-ID: <343bc90a-e502-4178-86ab-74e0fa4f33ff@linux.ibm.com> Date: Fri, 27 Feb 2026 21:27:26 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCHv2 2/3] nvme-multipath: rescan siblings on last path removal To: Keith Busch Cc: Keith Busch , linux-nvme@lists.infradead.org, hch@lst.de References: <20260226183216.2098584-1-kbusch@meta.com> <20260226183216.2098584-3-kbusch@meta.com> <7797a6a3-d47d-440c-a580-40bae546728a@linux.ibm.com> Content-Language: en-US From: Nilay Shroff In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: j4Y4NT63IEVUo3bpYYnA9C5ucp9eEdm2 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjI3MDE0MCBTYWx0ZWRfX0yTtZKZrAW5r tais/t1dZ+60NjcFeGsWYrns4/V6qcy1l1vQLl3VVYU84Svh+kWBJc5gnPXdt2pHO0XaNif3l+j hDm8ip3lV/wYCoK+WkOOQOyZHMJt6PEvWaPUTR9hjjvVcTNGceT31lmbBnvWtsAfHAiqvT3KZsf 5c2KXfdHUCDs3j9IFjii/KkWxAJ/ajgNKiaikpgK52yG5icyIVZTK5HnKonrf5j9g4BK96+WiKB q7xwVKr0D2ON6qYEWybHerZJNKRzCTBNmSSgzDjwb9LkGLORQ6V51ccR3DuYLJ4V/1DQdUjaPUh 38b2Lc/J/31Evc33u4dU9Sw4nRjqWC1YYOMalv9Epxp/hiZFSHtyExz0c3FcfhCCnV8ATjlLVu9 JiKxl0y6xkLo8+pOTI0mysiQZUeIBKdd7EWvy/3Vb0svaECy3vDyHAHZ/P4zdhUueuCabtChxpj 4kySO8n5UMPPtuHpXPw== X-Authority-Analysis: v=2.4 cv=eNceTXp1 c=1 sm=1 tr=0 ts=69a1beee cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=IkcTkHD0fZMA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22 a=Mpw57Om8IfrbqaoTuvik:22 a=GgsMoib0sEa3-_RKJdDe:22 a=VnNF1IyMAAAA:8 a=bZhc5tH6S1NQCDocyvMA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: j4Y4NT63IEVUo3bpYYnA9C5ucp9eEdm2 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-02-27_03,2026-02-27_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 priorityscore=1501 phishscore=0 suspectscore=0 adultscore=0 bulkscore=0 lowpriorityscore=0 malwarescore=0 impostorscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000 definitions=main-2602270140 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260227_075739_158622_DC2BC2FB X-CRM114-Status: GOOD ( 15.15 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 2/27/26 9:04 PM, Keith Busch wrote: > On Fri, Feb 27, 2026 at 12:29:00PM +0530, Nilay Shroff wrote: >> Should we consider reordering patches 2/3 and 3/3? It seems like this >> patch depends on the changes introduced in 3/3. >> >> Without the updates from 3/3, if delayed head removal is still in effect >> and the NSIDs are recycled with mismatched identifiers, a forced rescan >> of the sibling controller may still fail to instantiate the namespace. >> In that case, requeueing the scan alone might not be sufficient. > > But the other way around, if we're racing with another controller's scan > to complete the last path removal, then the delayed work hasn't been > scheduled yet so patch 3 has a significant gap without patch 2 preceding > it. Yes, that’s also correct — both patches depend on each other to some extent. If the user does not configure delayed_removal_sec, then patch 2 by itself is sufficient to resolve the race. So with that, overall, the changes look good to me: Reviewed-by: Nilay Shroff