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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: <20260219151729.GK1282955@noisy.programming.kicks-ass.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: 68pbn93a94zrnnfxmptc14h3p177yui1 X-Rspam-User: X-Rspamd-Queue-Id: 03D311C0018 X-Rspamd-Server: rspam01 X-HE-Tag: 1771514261-759484 X-HE-Meta: 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 irRkMsvL eOaqhxuamyXrjWDvjwoGz475XxnXDBpcigTLWfGwN0Y2IKwJIaWL9QSVdN9bNoJQ9Qekw+uHJrcDF5GUZPeJMjgysEpoZXxLCYl0NgSdO+QI/IRv7EoGOOt0/KfpDSIfqG1Qzx3KL8f9eedMKAqaWjFLnMcmDC+O91FTpoH1+J/jPPaPCeszM0El8mGJys/Cmj3VSpwg7cZLBmPvn/T/96AADmpRjKUqyEWo5SWZW0Mi4kGI= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Feb 19, 2026 at 03:08:51PM +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; > > I think we can benefit from separating these two meanings and allowing > order-0 allocations to be larger than the virtual address space covered by a > PTE entry. Didn't AA do this a decade ago or somesuch?