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[96.255.20.42]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7cd00f4e093sm568092885a.8.2025.05.12.09.38.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 May 2025 09:38:49 -0700 (PDT) Date: Mon, 12 May 2025 12:38:47 -0400 From: Gregory Price To: Matthew Wilcox Cc: linux-cxl@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, dave@stgolabs.net, jonathan.cameron@huawei.com, dave.jiang@intel.com, alison.schofield@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, dan.j.williams@intel.com, corbet@lwn.net Subject: Re: [PATCH v3 14/17] cxl: docs/allocation/page-allocator Message-ID: References: <20250512162134.3596150-1-gourry@gourry.net> <20250512162134.3596150-15-gourry@gourry.net> 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=us-ascii Content-Disposition: inline In-Reply-To: On Mon, May 12, 2025 at 05:34:56PM +0100, Matthew Wilcox wrote: > On Mon, May 12, 2025 at 12:21:31PM -0400, Gregory Price wrote: > > Document some interesting interactions that occur when exposing CXL > > memory capacity to page allocator. > > We should not do this. Asking the page allocator for memory (eg for > slab) should never return memory on CXL. There need to be special > interfaces for clients that know they can tolerate the added latency. > > NAK this concept, and NAK this specific document. I have no comment on > the previous documents. This describes what presently exists, so i'm not sure of what value a NAK here is. Feel free to submit patches that deletes the existing code if you want it removed from the documentation. ~Gregory