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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: <20260219152045.GR1395416@noisy.programming.kicks-ass.net> References: <20260219151729.GK1282955@noisy.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260219151729.GK1282955@noisy.programming.kicks-ass.net> X-Stat-Signature: xoattf4en3ed4jsqo6b4ohb4i5spyjjs X-Rspamd-Server: rspam11 X-Rspam-User: X-Rspamd-Queue-Id: 73E3820015 X-HE-Tag: 1771514454-590882 X-HE-Meta: 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 Iy3kfhuS eBpdY2P1MrgnNDIVfYQXnkLRg/dscF1rQwBRL7vFlzQsj0kR6J5lVgadpKRwyetAMhr+OLRN8Q/oUINt33biu7SLpZvBIgpX+dsX9xTt2UTCFPURafolFvdBBzUjJclQj5ShhxrragiRS2so1UNclR+JdEwP1w+ehNCGKQvRk5Qa6xak392GtIriW6q5USQkr/HNBOTiILg9aAU96zu5hx09Y6/ePLxl8gcDVyP8bqpHmYiHaZhQy53egh8hjOFi9dSRE4rIjlL1HfoY= 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 04:17:29PM +0100, Peter Zijlstra wrote: > 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? https://lwn.net/Articles/240914/