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[71.191.243.150]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8aca259724csm53270746d6.12.2026.04.13.12.59.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2026 12:59:16 -0700 (PDT) Date: Mon, 13 Apr 2026 15:59:14 -0400 From: Gregory Price To: "David Hildenbrand (Arm)" Cc: Andrew Morton , linux-mm@kvack.org, vishal.l.verma@intel.com, dave.jiang@intel.com, osalvador@suse.de, dan.j.williams@intel.com, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH 0/8] dax/kmem: atomic whole-device hotplug via sysfs Message-ID: References: <20260321150404.3288786-1-gourry@gourry.net> <20260321104021.4a6074330131a2058e8706bd@linux-foundation.org> <478c5700-8bf5-42b9-ad71-bbc618b36c9c@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <478c5700-8bf5-42b9-ad71-bbc618b36c9c@kernel.org> On Mon, Apr 13, 2026 at 09:40:49PM +0200, David Hildenbrand (Arm) wrote: > > > > I don't think this is a very large lift, just a slightly larger hotplug > > locking scope. But then - the per-range thing in this set should just > > work, so let me know if it's worth the extra churn. > > Well, you can rather cleanly undo the operation if any offlining fails. > If that's not a requirement, then no need to change it! > It's not a requirement for me, but maybe it makes sense that echo unplug > dax0.0/hotplug Either fully succeeds or fully rolls back. Otherwise `cat hotplug` would have to report "¯\_(ツ)_/¯". So makes sense, i'll come back around on this. ~Gregory