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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-483a31f995dsm57350025e9.13.2026.02.20.01.04.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Feb 2026 01:04:10 -0800 (PST) Date: Fri, 20 Feb 2026 09:04:09 +0000 From: David Laight To: Kiryl Shutsemau Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, x86@kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , David Hildenbrand , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Matthew Wilcox , Johannes Weiner , Usama Arif Subject: Re: [LSF/MM/BPF TOPIC] 64k (or 16k) base page size on x86 Message-ID: <20260220090409.1784bc64@pumpkin> In-Reply-To: References: X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) 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-Transfer-Encoding: 7bit On Thu, 19 Feb 2026 15:08:51 +0000 Kiryl Shutsemau wrote: > No, there's no new hardware (that I know of). I want to explore what page size > means. > > The kernel uses the same value - PAGE_SIZE - for two things: > > - the order-0 buddy allocation size; > > - the granularity of virtual address space mapping; Also the 'random' buffers that are PAGE_SIZE rather than 4k. I also wonder how is affects mmap of kernel memory and the alignement of PCIe windows (etc). David