From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BDBA3CA0FED for ; Wed, 10 Sep 2025 20:33:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:Subject:References:In-Reply-To:Message-ID:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Xn32CgfsCdcgiZc5xVsldvxbovwbLiKF6pDU6aeqlX8=; b=Be7jYHv215yr9+oXVu6cvbnnfN PRtWfFAPhYyb8yTzE7/zsNpnB79k0y/5sjvV/XijOnyB7x3ZjQDObcvoGCZbQGU5/12yUgAPz6sKR wnkva1ylkT1IHEtU2jKfPrZoPdM8mlUGBW0pFGd5e9MWCdzSd3BDWic+nYJJS3cWX+N8IBAHV72yJ M6iBg9VgWspe6RlpgbUFxhrPmsxsu8yuBnfWsRZliCc3yfkp/HDtYt6ITcI8YI2MeldqMN5N21SS0 HpojLYmc5V9sCpuOsd3NMadDIFVLWutTKXrMN2SOjWvSyPZqWQ98MC9w79zofNTOmvRbiDg3O7uYG BWoHQRJA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uwRVJ-0000000GZvi-0uaR; Wed, 10 Sep 2025 20:33:21 +0000 Received: from mailout.nod.at ([116.203.167.152] helo=lithops.sigma-star.at) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uwRVG-0000000GZqt-0hpE for linux-arm-kernel@lists.infradead.org; Wed, 10 Sep 2025 20:33:19 +0000 Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 511D5CE34D; Wed, 10 Sep 2025 22:33:07 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id aSKreuvdlGXI; Wed, 10 Sep 2025 22:33:06 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 4BFD3CE34E; Wed, 10 Sep 2025 22:33:06 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id YO9RM-IU3T_L; Wed, 10 Sep 2025 22:33:06 +0200 (CEST) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id 082B5CE34D; Wed, 10 Sep 2025 22:33:06 +0200 (CEST) Date: Wed, 10 Sep 2025 22:33:05 +0200 (CEST) From: Richard Weinberger To: Dave Hansen Cc: Arnd Bergmann , ksummit , linux-kernel , linux-arm-kernel , linuxppc-dev , linux-mips , linux-mm , imx , Christophe Leroy , Lucas Stach , Linus Walleij , Geert Uytterhoeven , Ankur Arora , David Hildenbrand , Mike Rapoport , Lorenzo Stoakes , Matthew Wilcox , Andrew Morton , "Liam R. Howlett" , vbabka , Suren Baghdasaryan , Ira Weiny , Nishanth Menon , heiko , Alexander Sverdlin , "Chester A. Unal" , Sergio Paracuellos , Andreas Larsson Message-ID: <640041197.22387.1757536385810.JavaMail.zimbra@nod.at> In-Reply-To: References: <4ff89b72-03ff-4447-9d21-dd6a5fe1550f@app.fastmail.com> <497308537.21756.1757513073548.JavaMail.zimbra@nod.at> Subject: Re: [TECH TOPIC] Reaching consensus on CONFIG_HIGHMEM phaseout MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [195.201.40.130] X-Mailer: Zimbra 8.8.12_GA_3807 (ZimbraWebClient - FF141 (Linux)/8.8.12_GA_3809) Thread-Topic: Reaching consensus on CONFIG_HIGHMEM phaseout Thread-Index: qX92QwLBi0un/69XQpQP6tb4aScRlQ== X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250910_133318_347077_81EC0BF9 X-CRM114-Status: GOOD ( 11.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Dave, ----- Urspr=C3=BCngliche Mail ----- > Von: "Dave Hansen" >> Even with a new memory split, which could utilize most of the >> available memory, I expect there to be issues with various >> applications and FPGA device drivers. > I'd be really curious what the _actual_ issues would be with a > non-standard split. There are a lot of "maybe" problems and solutions > here, but it's hard to move forward without known practical problems to > tackle. >=20 > Has anybody run into actual end user visible problems when using one of > weirdo PAGE_OFFSET configs? In the past I saw that programs such as the Java Runtime (JRE) ran into address space limitations due to a 2G/2G split on embedded systems. Reverting to a 3G/1G split fixed the problems. Thanks, //richard