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Fri, 14 Aug 2026 06:27:15 -0700 (PDT) Date: Fri, 14 Aug 2026 09:27:09 -0400 From: Gregory Price To: Pankaj Gupta Cc: linux-mm@kvack.org, Zhigang.Luo@amd.com, arun.george@samsung.com, balbirs@nvidia.com, brendan.jackman@linux.dev, yuzenghui@huawei.com, apopple@nvidia.com, alucerop@amd.com, matthew.brost@intel.com, akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, corbet@lwn.net, skhan@linuxfoundation.org, gregkh@linuxfoundation.org, rafael@kernel.org, dakr@kernel.org, djbw@kernel.org, "Gupta, Pankaj" , vishal.l.verma@intel.com, dave.jiang@intel.com, alison.schofield@intel.com, osandov@osandov.com, jannh@google.com, pfalcato@suse.de, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com, pbonzini@redhat.com, osalvador@suse.de, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, kasong@tencent.com, qi.zheng@linux.dev, shakeel.butt@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, yury.norov@gmail.com, linux@rasmusvillemoes.dk, longman@redhat.com, ridong.chen@linux.dev, tj@kernel.org, mkoutny@suse.com, sj@kernel.org, jgg@ziepe.ca, jhubbard@nvidia.com, peterx@redhat.com, baolin.wang@linux.alibaba.com, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, lance.yang@linux.dev, usama.arif@linux.dev, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, roman.gushchin@linux.dev, muchun.song@linux.dev, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, driver-core@lists.linux.dev, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-debuggers@vger.kernel.org, linux-fsdevel@vger.kernel.org, kvm@vger.kernel.org, cgroups@vger.kernel.org, damon@lists.linux.dev, linux-kselftest@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH v5 00/36] Private Memory NUMA Nodes Message-ID: References: <20260720193431.3841992-1-gourry@gourry.net> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Aug 13, 2026 at 10:55:13AM +0200, Pankaj Gupta wrote: > > > > A device driver could very well just call memory-hotplug directly, > > or its memory could be brought up as a private node via a boot > > paremeter (which I have sculpted for v7). The former is preferred, > > but there's a bit of a chicken/egg scenario for bootstrapping. > > I find this interesting as this appears to be evolving towards a vendor > agnostic framework for hotplugging memory directly to private nodes. > Agnostic would depend on a common standard for such devices. Otherwise, there is still a need for per-device drivers - but hopefully the interaction itself can be generalized. > How you see this working? In particular, How would the kernel know which > memory ranges correspond to HBM or other device memory? > Device marks the region reserved at boot, driver hotplugs. or Device marks the region normal, but boot param sets the node private. > Please also CC me when you post v7: pankaj.gupta@amd.com > Sure ~Gregory