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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> 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> X-Rspamd-Queue-Id: 445901C000C X-Stat-Signature: kgfcr3duarszqujcmqxip6y4zjbeb6e1 X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1776110358-326301 X-HE-Meta: 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 6S1krXGl h+j1YnzaFBm0BGB9hhSeX9YQ5dSK0XeaOh0n/Dr2qpzwsovEnknvoR+ciEnE9K9cBFs4KxRuN35prn9SBfwAHwqaqfuJV9qio9OF9ZMSYkRy6FWj1kUAp3mqiepY4h6fHnzzflif3gNQVEacJlN44kzRfxSs757q1fFWxX4A0B8YYFxQ/I7FN3qSOq437/MNfcyh0dJwhoGecGtbGv81a+NqzQPGNjXUjIcIXswhPFhzY3pT+NzqqUXCRIsmI0z5i5LOcNlzBEdkfDTfnFn1i2xmf4M7NRfu01h3QiRNV1kKjm1We7gVR9zTYUoKUM7lWueiyfPR1fTD63bKtsNEO3N2LoOE+MeiwBShO Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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