From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-42a8.mail.infomaniak.ch (smtp-42a8.mail.infomaniak.ch [84.16.66.168]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C4612DC76C for ; Sun, 19 Jul 2026 22:40:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=84.16.66.168 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784500837; cv=none; b=ThCu66yUDWLgLgGRf00ld0zQyaCPmBXIdTxqT3Zp2YD4wLruQ0AiA9SJ5RTRku2rPbin+K8tO67pZkvbHO5HbkdOpow/yXyC/D2t8lwgomYwcdTNXicv3QengvPiT2/Berk/tx+jJymJSZ+hOa8GstdMd2fJENWl9OllbCwmcIo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784500837; c=relaxed/simple; bh=z/As3jh9J+Ri5350i8gIWsDUlERwPDa465oZg/kBHcQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VgHKIlWAm2F0sDE1Po0FXXrqQ8uBORvZiRnFWT2LfgjkhYPVr253WqUOrYc72UKl6Sfq+r8Huiu6BmRDmQoh+C6r70bUxqv5ws0hMXh1V1lQ7Ti5YqxuJbml+STtj4klCLqoMEqOUq/GqrfWVvFr2NKnYvNFOWvTSZgV0Mm5WHk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ik.me; spf=pass smtp.mailfrom=ik.me; dkim=pass (1024-bit key) header.d=ik.me header.i=@ik.me header.b=LJk+VVcg; arc=none smtp.client-ip=84.16.66.168 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ik.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ik.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ik.me header.i=@ik.me header.b="LJk+VVcg" Received: from smtp-3-0000.mail.infomaniak.ch (smtp-3-0000.mail.infomaniak.ch [10.4.36.107]) by smtp-3-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4h3JKk6t97zQlg; Mon, 20 Jul 2026 00:31:54 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ik.me; s=20200325; t=1784500314; bh=wM1/+Ssl5lb/f8P5nWzlhL+7cN81hvJNcfIMkDKJQJM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LJk+VVcgpPTVwDgGzASJk8W6JvdF0ueL6YzhxX43xjN5jtCft3Yc80T+0Qmeuld4T RxAZ2BFGifR8sc7DSuQ4r7nPmWBs7dViyKqk1KA3f53HA6XTz4AV/P+usTXBbI6CvE A9QXcFb2ZoJ9bbYEi8S7JhoWomdWOqr0tmpn4G3c= Received: from unknown by smtp-3-0000.mail.infomaniak.ch (Postfix) with ESMTPA id 4h3JKj0jRszgmr; Mon, 20 Jul 2026 00:31:53 +0200 (CEST) Date: Mon, 20 Jul 2026 00:31:51 +0200 From: Nadia Chambers To: David Laight Cc: Kiryl Shutsemau , 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: References: <20260220090409.1784bc64@pumpkin> 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=utf-8 Content-Disposition: inline In-Reply-To: <20260220090409.1784bc64@pumpkin> Feedback-ID: :965687c8d9b437c:ham:b89b32586f6d122 X-Infomaniak-Routing: alpha 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; Am Fr, Feb 20, 2026 um 09:04:09 +0000, David Laight schrieb: > 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). It doesn't. Any adequate implementation has to sweep drivers and update them to use MMUPAGE_SIZE or other address calculations that are still correct for device memory, buffers need sizing so they work usw. Yes, those things are there. Sweeping them is integral to implementing page clustering, whether it was Hugh, me, Andrea or Kiryl. -- nyc