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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8899BC35242 for ; Wed, 12 Feb 2020 01:03:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D9792070A for ; Wed, 12 Feb 2020 01:03:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581469404; bh=I1KoEB2fG4nytg4dHf2NGPU53q0vfjTuTQg4v8g1oEY=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=UWqzB40EmlwSiezP7lfQC2eGdEStRIXwif9RSfd34wDeCt6TMkmQDY8tEy/ogxMIB XX0VwGlBPG5aBtSDe/M7jodOzPJdI6E2KBfwgI0ppe1QTJ7X5cxPrFuUiTaSxP0d8N zwfgRtMZDeV/IegVuSnWUHq+MNKui7JF35XGafes= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728198AbgBLBDX (ORCPT ); Tue, 11 Feb 2020 20:03:23 -0500 Received: from mail-lf1-f68.google.com ([209.85.167.68]:43618 "EHLO mail-lf1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728120AbgBLBDX (ORCPT ); Tue, 11 Feb 2020 20:03:23 -0500 Received: by mail-lf1-f68.google.com with SMTP id 9so287476lfq.10 for ; Tue, 11 Feb 2020 17:03:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=fBxG1HcrByKfPtNty2DhtyD54YlVBt8nIN51NK2VPpgZ7L26CoMAQYrrNez+Edd1Gn KLAHlVWkm3Q8uZOGQqKfncW351w+GkpekQ1AxurxF26lO2WmqXR1y7xwYNvUiRUf7dX7 p/ZI6Bsp5G+eMc0JFhnEsMBjvUERkEUAYwFn4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=ZKWadedcZD7fAVq3sV07DzLHxvvzXPviicDhNaQvTuRPHnVnAeGAYX7InJrEVHJw15 gA1oVUAKnm98uAluu8hBMCO6Z8N70YH5KJ8+WSDNGbGVFp5nKj2fG6b0MznAMh63RJUl d4NId4yrDVFVG13OvMe9bS4ZipQ0AuC9vTnxdT7tjcGu4mChlogbyVOUJpqfc80tEucY RWfy00N68xmoRId77nNkg4oqVoeVn1SV06bjhlcNkdhUb3Ry0PfCC3t4dWg4GA8SdXZ+ nnhiBJ+ij6AEZQG26j8EzMqczw0TtAFuGYkpMoBY0IIWedh2rLyLQM8tC8cte/wXeDM/ G4dA== X-Gm-Message-State: APjAAAUfE0olNAaZr/IWuevBWVhOEhTFbCT3RyTOKFXzIyIimAZ9Qbwj 0c/+v+qIywgahyuJ6kNqBS8y27fPfuE= X-Google-Smtp-Source: APXvYqwZ6Q1zdaKgFPmmBgS/4YPfvd0M4L1YbdQ+VSwHzessMM5cGPgjachiTZf8ZTIuqaT/navcQA== X-Received: by 2002:a19:48c5:: with SMTP id v188mr5257655lfa.100.1581469400021; Tue, 11 Feb 2020 17:03:20 -0800 (PST) Received: from mail-lj1-f181.google.com (mail-lj1-f181.google.com. [209.85.208.181]) by smtp.gmail.com with ESMTPSA id y29sm2944267ljd.88.2020.02.11.17.03.18 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Feb 2020 17:03:19 -0800 (PST) Received: by mail-lj1-f181.google.com with SMTP id y6so334724lji.0 for ; Tue, 11 Feb 2020 17:03:18 -0800 (PST) X-Received: by 2002:a2e:580c:: with SMTP id m12mr6104508ljb.150.1581469398565; Tue, 11 Feb 2020 17:03:18 -0800 (PST) MIME-Version: 1.0 References: <20200211175507.178100-1-hannes@cmpxchg.org> <29b6e848ff4ad69b55201751c9880921266ec7f4.camel@surriel.com> <20200211193101.GA178975@cmpxchg.org> <20200211154438.14ef129db412574c5576facf@linux-foundation.org> <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> In-Reply-To: <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> From: Linus Torvalds Date: Tue, 11 Feb 2020 17:03:02 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] vfs: keep inodes with page cache off the inode shrinker LRU To: Andrew Morton , Russell King , Linux ARM , Catalin Marinas Cc: Johannes Weiner , Rik van Riel , linux-fsdevel , Linux-MM , Linux Kernel Mailing List , Dave Chinner , Yafang Shao , Michal Hocko , Roman Gushchin , Al Viro , kernel-team@fb.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 11, 2020 at 4:47 PM Andrew Morton wrote: > > What's the situation with highmem on ARM? Afaik it's exactly the same as highmem on x86 - only 32-bit ARM ever needed it, and I was ranting at some people for repeating all the mistakes Intel did. But arm64 doesn't need it, and while 32-bit arm is obviosuly still selling, I think that in many ways the switch-over to 64-bit has been quicker on ARM than it was on x86. Partly because it happened later (so all the 64-bit teething pains were dealt with), but largely because everybody ended up actively discouraging 32-bit on the Android side. There were a couple of unfortunate early 32-bit arm server attempts, but they were - predictably - complete garbage and nobody bought them. They don't exist any more. So at least my gut feel is that the arm people don't have any big reason to push for maintaining HIGHMEM support either. But I'm adding a couple of arm people and the arm list just in case they have some input. [ Obvious background for newly added people: we're talking about making CONFIG_HIGHMEM a deprecated feature and saying that if you want to run with lots of memory on a 32-bit kernel, you're doing legacy stuff and can use a legacy kernel ] Linus 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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8419BC3B187 for ; Wed, 12 Feb 2020 01:03:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 322D420842 for ; Wed, 12 Feb 2020 01:03:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="fBxG1Hcr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 322D420842 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 833826B0384; Tue, 11 Feb 2020 20:03:24 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7E4B06B0385; Tue, 11 Feb 2020 20:03:24 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6AC876B0386; Tue, 11 Feb 2020 20:03:24 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0028.hostedemail.com [216.40.44.28]) by kanga.kvack.org (Postfix) with ESMTP id 53ED26B0384 for ; Tue, 11 Feb 2020 20:03:24 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DF185180AD804 for ; Wed, 12 Feb 2020 01:03:23 +0000 (UTC) X-FDA: 76479676686.13.pot29_3ab337d736526 X-HE-Tag: pot29_3ab337d736526 X-Filterd-Recvd-Size: 5193 Received: from mail-lf1-f68.google.com (mail-lf1-f68.google.com [209.85.167.68]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Wed, 12 Feb 2020 01:03:23 +0000 (UTC) Received: by mail-lf1-f68.google.com with SMTP id r14so305282lfm.5 for ; Tue, 11 Feb 2020 17:03:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=fBxG1HcrByKfPtNty2DhtyD54YlVBt8nIN51NK2VPpgZ7L26CoMAQYrrNez+Edd1Gn KLAHlVWkm3Q8uZOGQqKfncW351w+GkpekQ1AxurxF26lO2WmqXR1y7xwYNvUiRUf7dX7 p/ZI6Bsp5G+eMc0JFhnEsMBjvUERkEUAYwFn4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=K4upII0eVyov6dS0Yd0gBtJmTKB51BhbhZNgyGeSNBiLUm2FEmW1eS2jGDc574sSpt //or/zUjRmL+dVgo/eeiCDQKYQYKIQOEh/SPtquL5WBijnzizyKjXacLiqTXzwegzhyQ phIkIG4fre1FsHQ+Ib7l4INiA5CG7noRztUWhIW8aTOKJntznBCSOFItWunltKwykmY0 sVbjRPwp8pFwHMGtEEXgw+eO/PzAdiYadtjE6frQx1S320wGfoyVnQjCRvaGiYV7OpIM atfTWufzMZesNC731IfKEpJpqfbjLQu84zZ6bb9ReiRiWf3/Oi4KLp15EZk9GrXNR5aa VbIQ== X-Gm-Message-State: APjAAAUNhtOF8zaUCUXjlIhqEdmB6Q8XmDwfrcVh9mRPa3YOmh2kUToL 7A6o4TkbQ1kDZxMgZc8VrBsvDrf8aUY= X-Google-Smtp-Source: APXvYqzBe3Wo1mbU7gbBnmQXSIxdtzXSgoKVaVcmtRJhijPU+P9Vo7veTfeIci3oWn6bf67yYRriwg== X-Received: by 2002:ac2:46dc:: with SMTP id p28mr5144307lfo.23.1581469400670; Tue, 11 Feb 2020 17:03:20 -0800 (PST) Received: from mail-lj1-f170.google.com (mail-lj1-f170.google.com. [209.85.208.170]) by smtp.gmail.com with ESMTPSA id u19sm2585350lfu.68.2020.02.11.17.03.19 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Feb 2020 17:03:20 -0800 (PST) Received: by mail-lj1-f170.google.com with SMTP id x7so328662ljc.1 for ; Tue, 11 Feb 2020 17:03:19 -0800 (PST) X-Received: by 2002:a2e:580c:: with SMTP id m12mr6104508ljb.150.1581469398565; Tue, 11 Feb 2020 17:03:18 -0800 (PST) MIME-Version: 1.0 References: <20200211175507.178100-1-hannes@cmpxchg.org> <29b6e848ff4ad69b55201751c9880921266ec7f4.camel@surriel.com> <20200211193101.GA178975@cmpxchg.org> <20200211154438.14ef129db412574c5576facf@linux-foundation.org> <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> In-Reply-To: <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> From: Linus Torvalds Date: Tue, 11 Feb 2020 17:03:02 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] vfs: keep inodes with page cache off the inode shrinker LRU To: Andrew Morton , Russell King , Linux ARM , Catalin Marinas Cc: Johannes Weiner , Rik van Riel , linux-fsdevel , Linux-MM , Linux Kernel Mailing List , Dave Chinner , Yafang Shao , Michal Hocko , Roman Gushchin , Al Viro , kernel-team@fb.com Content-Type: text/plain; charset="UTF-8" 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: On Tue, Feb 11, 2020 at 4:47 PM Andrew Morton wrote: > > What's the situation with highmem on ARM? Afaik it's exactly the same as highmem on x86 - only 32-bit ARM ever needed it, and I was ranting at some people for repeating all the mistakes Intel did. But arm64 doesn't need it, and while 32-bit arm is obviosuly still selling, I think that in many ways the switch-over to 64-bit has been quicker on ARM than it was on x86. Partly because it happened later (so all the 64-bit teething pains were dealt with), but largely because everybody ended up actively discouraging 32-bit on the Android side. There were a couple of unfortunate early 32-bit arm server attempts, but they were - predictably - complete garbage and nobody bought them. They don't exist any more. So at least my gut feel is that the arm people don't have any big reason to push for maintaining HIGHMEM support either. But I'm adding a couple of arm people and the arm list just in case they have some input. [ Obvious background for newly added people: we're talking about making CONFIG_HIGHMEM a deprecated feature and saying that if you want to run with lots of memory on a 32-bit kernel, you're doing legacy stuff and can use a legacy kernel ] Linus 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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2570AC35242 for ; Wed, 12 Feb 2020 01:03:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id CC6CE2070A for ; Wed, 12 Feb 2020 01:03:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="d4OZ+MoA"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="fBxG1Hcr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC6CE2070A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Ri6YWvEgdYBP5Fu0FOSuRy3h+FfoI6lEgJVAYCrt+4U=; b=d4OZ+MoA4fduPv oiEd4Umc5K/5V+NXr8BGsT0zPxC8ZamhhwPKk+qOo9HkozvJJomlif1uwqwnUtbzxvF7whEJWpazN lRT9p5lDlQY7DZhX8qiRH2fcTmgZ5hoWOZd2O31MLJy4g7BD1GDal622BvpFNn3iLO9pDnWcrdnS4 Bw1uW011ItMIsYGinLAzT7GlwMKvM/8MtGkKwmXw9D3eKkY2w8pI/ONSpALEbYVhUXNDcQiAnP/38 jy9vgOAB9/+qveg3KiS8xP9dreqSsC6bDWZdefsN6qeseCpYr2D6IGyC27/nGoZ7CrNmGx4FCra+U osTQHTOxUW8ZTTx7XZiw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j1gR9-0006Tv-Am; Wed, 12 Feb 2020 01:03:31 +0000 Received: from mail-lf1-x144.google.com ([2a00:1450:4864:20::144]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j1gR1-0006SZ-KU for linux-arm-kernel@lists.infradead.org; Wed, 12 Feb 2020 01:03:29 +0000 Received: by mail-lf1-x144.google.com with SMTP id 9so287497lfq.10 for ; Tue, 11 Feb 2020 17:03:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=fBxG1HcrByKfPtNty2DhtyD54YlVBt8nIN51NK2VPpgZ7L26CoMAQYrrNez+Edd1Gn KLAHlVWkm3Q8uZOGQqKfncW351w+GkpekQ1AxurxF26lO2WmqXR1y7xwYNvUiRUf7dX7 p/ZI6Bsp5G+eMc0JFhnEsMBjvUERkEUAYwFn4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=zy6kGEEkqAsEiZzWHqRtvxnsI6DtM6n9AdiuD2GudTU=; b=N5wQ0xc3+Q3uG4cUNpYSPiqTK9d284vGHg+F8Lsg1j8B5TmsFPGd7y1NfpE8X/W++w L/bba/FHB7UJg4l+nYdlGKLPvdxrK7K2Z2xpImmcqoSCOYk6sktv109W0AmVlKJE7Vif iIl0nUexUWNAM+n2ff88ANXaZGdI6JoU4KqCHDaQ45o1WUA7NWv/Txj4Dx6UzXg42EJg sPrIpuxsabzgFiIAtaHo8u91IlRiRUS7ZjWxoJVLdCQhBVkCfbBhohIWGo2gk+i8uRWH lQ3PmW/9H0zjKdWmrh7K9loklK9YxRMEHKUXuA96vb4pW/y7nD1C+oI3AMAIqnbQwgvv biSQ== X-Gm-Message-State: APjAAAXfsx493u9Jm89DuUm10EJNxdjrhiEGcgzRYjkH2N+aGYXPuIOT 7leb0ZA6TGDODqSlZ2SyFgLqDC6TC24= X-Google-Smtp-Source: APXvYqwdUDunt7Eo22hpClDQ+KT+sBQdhLzmS3LzkneDpxcHNQlYh95p6XjUx+NOnSr1Wi49BKktpg== X-Received: by 2002:a19:84d:: with SMTP id 74mr4953170lfi.122.1581469400462; Tue, 11 Feb 2020 17:03:20 -0800 (PST) Received: from mail-lj1-f172.google.com (mail-lj1-f172.google.com. [209.85.208.172]) by smtp.gmail.com with ESMTPSA id o69sm2580398lff.14.2020.02.11.17.03.19 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Feb 2020 17:03:20 -0800 (PST) Received: by mail-lj1-f172.google.com with SMTP id n18so298551ljo.7 for ; Tue, 11 Feb 2020 17:03:19 -0800 (PST) X-Received: by 2002:a2e:580c:: with SMTP id m12mr6104508ljb.150.1581469398565; Tue, 11 Feb 2020 17:03:18 -0800 (PST) MIME-Version: 1.0 References: <20200211175507.178100-1-hannes@cmpxchg.org> <29b6e848ff4ad69b55201751c9880921266ec7f4.camel@surriel.com> <20200211193101.GA178975@cmpxchg.org> <20200211154438.14ef129db412574c5576facf@linux-foundation.org> <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> In-Reply-To: <20200211164701.4ac88d9222e23d1e8cc57c51@linux-foundation.org> From: Linus Torvalds Date: Tue, 11 Feb 2020 17:03:02 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] vfs: keep inodes with page cache off the inode shrinker LRU To: Andrew Morton , Russell King , Linux ARM , Catalin Marinas X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200211_170323_684759_A7803A68 X-CRM114-Status: GOOD ( 11.78 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michal Hocko , Rik van Riel , Dave Chinner , Linux Kernel Mailing List , Linux-MM , Yafang Shao , Al Viro , Johannes Weiner , linux-fsdevel , kernel-team@fb.com, Roman Gushchin Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Feb 11, 2020 at 4:47 PM Andrew Morton wrote: > > What's the situation with highmem on ARM? Afaik it's exactly the same as highmem on x86 - only 32-bit ARM ever needed it, and I was ranting at some people for repeating all the mistakes Intel did. But arm64 doesn't need it, and while 32-bit arm is obviosuly still selling, I think that in many ways the switch-over to 64-bit has been quicker on ARM than it was on x86. Partly because it happened later (so all the 64-bit teething pains were dealt with), but largely because everybody ended up actively discouraging 32-bit on the Android side. There were a couple of unfortunate early 32-bit arm server attempts, but they were - predictably - complete garbage and nobody bought them. They don't exist any more. So at least my gut feel is that the arm people don't have any big reason to push for maintaining HIGHMEM support either. But I'm adding a couple of arm people and the arm list just in case they have some input. [ Obvious background for newly added people: we're talking about making CONFIG_HIGHMEM a deprecated feature and saying that if you want to run with lots of memory on a 32-bit kernel, you're doing legacy stuff and can use a legacy kernel ] Linus _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel