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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 D4E2BC2BA19 for ; Tue, 14 Apr 2020 11:41:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2ECA2076B for ; Tue, 14 Apr 2020 11:41:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ocqZqq6s" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439473AbgDNLll (ORCPT ); Tue, 14 Apr 2020 07:41:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2439459AbgDNLlg (ORCPT ); Tue, 14 Apr 2020 07:41:36 -0400 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F06D3C061A0C; Tue, 14 Apr 2020 04:41:35 -0700 (PDT) Received: by mail-pl1-x644.google.com with SMTP id t4so4540275plq.12; Tue, 14 Apr 2020 04:41:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:subject:to:cc:references:in-reply-to:mime-version :message-id:content-transfer-encoding; bh=8Esq4uJjc7hCqZPSyfuH3UXfV8N/MZeW3NHhinZ8EQA=; b=ocqZqq6sP10NyE5Oqrsyu24BO4bUv9d+CybYLvjUEA0qRTbQq8IAo2pJTWQfIqu4RO sPTYsA+WN55nEjfpiAKwJ3efgvE0y02zIRGr4QJLeGvUEOTkWEwmF8lPwgWo+rxrPEs5 VDTf42M1YbD+ARAsRZhdeD47bvnZpwfdPk63IxzHlEP4FOS+xZOTFLokGOmvq6qCsYSC 9tfWtMbUwXgESksl6KkJnUtYDYhwxUwpcnrbpFt8xAH3B/hJvFo4WpPegEXCjs4dhUzZ W26SU5gqovyT9qgqJ6qWu6cT8BV0oBUpmf+pSVOyif6EAbW821Qd95yr49cfUdak8sxQ mhEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:subject:to:cc:references:in-reply-to :mime-version:message-id:content-transfer-encoding; bh=8Esq4uJjc7hCqZPSyfuH3UXfV8N/MZeW3NHhinZ8EQA=; b=WGFvk2eopzzhnzAKMqczAIyD6wLlBVfs7PY3INiZdxfU4MPoGd4n3TTWjqarVcnweU C5Yt9OmQcvvdATPOIYsmM1eOXWh0r4RUve1Me1zIlD6+oqn2mXTKOVexUMrQ1Ov+/o0X ynOXyCsBNxbUJlVv0/wwC/ZkXbv4XCxbcLcSRlPLyTi6IEgqAjHU7pp70Qm47VbQa8ws Jf3MRlCZfJv0WkX8lIv3Wu3p5whHDO113j81OCw19rXVwykUvjsP5Uc/P1H7L3FI/5BQ MUYifou97+SfNF2BarIGH0Re0WqMR+xW+pdPB0CanvoGes7kyAcQxhxrkQnC/O1YhLYa EaMw== X-Gm-Message-State: AGi0PuYM1E+KZqhuTkSMqNpb470s3CdfuWvXcLewXGUJuc9u8cjggT1f v1t7DbgwdN962Kd9Oo4Vx+k= X-Google-Smtp-Source: APiQypLIBjtk6RQd/AotCq9xnqN6ML09PMuOg/nS9Dm4xLrHmr38av9P0xvvmudk1+K5veWBSwJi4w== X-Received: by 2002:a17:90a:2281:: with SMTP id s1mr27766299pjc.68.1586864495571; Tue, 14 Apr 2020 04:41:35 -0700 (PDT) Received: from localhost ([203.18.28.220]) by smtp.gmail.com with ESMTPSA id 132sm11155833pfc.183.2020.04.14.04.41.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Apr 2020 04:41:35 -0700 (PDT) Date: Tue, 14 Apr 2020 21:39:53 +1000 From: Nicholas Piggin Subject: Re: [PATCH v2 4/4] mm/vmalloc: Hugepage vmalloc mappings To: Matthew Wilcox Cc: Borislav Petkov , Catalin Marinas , "H. Peter Anvin" , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Ingo Molnar , Thomas Gleixner , Will Deacon , x86@kernel.org References: <20200413125303.423864-1-npiggin@gmail.com> <20200413125303.423864-5-npiggin@gmail.com> <20200413134106.GN21484@bombadil.infradead.org> In-Reply-To: <20200413134106.GN21484@bombadil.infradead.org> MIME-Version: 1.0 Message-Id: <1586863931.xb4yeowkao.astroid@bobo.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Excerpts from Matthew Wilcox's message of April 13, 2020 11:41 pm: > On Mon, Apr 13, 2020 at 10:53:03PM +1000, Nicholas Piggin wrote: >> +static int vmap_pages_range_noflush(unsigned long start, unsigned long = end, >> + pgprot_t prot, struct page **pages, >> + unsigned int page_shift) >> +{ >> + if (page_shift =3D=3D PAGE_SIZE) { >=20 > ... I think you meant 'page_shift =3D=3D PAGE_SHIFT' Thanks, good catch. I obviously didn't test the fallback path (the other path works for small pages, it just goes one at a time). > Overall I like this series, although it's a bit biased towards CPUs > which have page sizes which match PMD/PUD sizes. It doesn't offer the > possibility of using 64kB page sizes on ARM, for example. No, it's just an incremental step on existing huge vmap stuff in tree, so such a thing would be out of scope. > But it's a > step in the right direction. >=20 I don't know about moving kernel maps away from a generic Linux page table format. I quite like moving to it and making it as generic as possible. On the other hand, I also would like to make some arch-specific allowances for certain special cases that may not fit within the standard page table format, but it might be a much more specific and limited interface than the general vmalloc stuff. Thanks, Nick