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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: References: <20260219151729.GK1282955@noisy.programming.kicks-ass.net> <20260219152045.GR1395416@noisy.programming.kicks-ass.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: <20260219152045.GR1395416@noisy.programming.kicks-ass.net> On Thu, Feb 19, 2026 at 04:20:45PM +0100, Peter Zijlstra wrote: > 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/ Oh, 2007. It predates me in kernel. Will read up. Thanks! -- Kiryl Shutsemau / Kirill A. Shutemov