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=-4.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_PASS,URIBL_BLOCKED autolearn=ham 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 26E6EC43444 for ; Sun, 6 Jan 2019 01:51:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF720222CC for ; Sun, 6 Jan 2019 01:51:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="Um4YEyAt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726405AbfAFBvX (ORCPT ); Sat, 5 Jan 2019 20:51:23 -0500 Received: from mail-lf1-f66.google.com ([209.85.167.66]:41321 "EHLO mail-lf1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726377AbfAFBvW (ORCPT ); Sat, 5 Jan 2019 20:51:22 -0500 Received: by mail-lf1-f66.google.com with SMTP id c16so27835300lfj.8 for ; Sat, 05 Jan 2019 17:51:20 -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=AcswdOBczXk+iMEaWZLv2123bIfAtssmPcZQKRLxpec=; b=Um4YEyAt8jYVvSh/qfFiqPF+GCGUMUEdHNIOKX3UpSSg+Jiiq+gkn8CZUF4jdBJxd5 ZcIyf17YCpILnvKPAgOoflI/KyDQRA5TVSSZoMnoaUCNfSp9CUyGyNuqDxtLhGzrhKXo B7zTL8Hn+Ok5KsEFJHpktWBjGUYOLesmk/W0o= 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=AcswdOBczXk+iMEaWZLv2123bIfAtssmPcZQKRLxpec=; b=nSrO/JVME32GYDhbr1rkUodQ2el8eu/vDPQnEts6BzyCeLrX5QiVqUHc3pquA/gPHC dYlFgzyGfY7SeC0SNqtKdzII7kJLxzlM1/rKU1GRfV8nJRvG1shaen9+joOKRJE6+gko WyJkcg+Ej9eEBlLdBk3HiArfCdyJb9nQn7Jojqfgvm82IC445wT112i1MAuJ0UHfozb7 oedO/F4dBqvdH0Dq4EGDGBd7IIzpntQ9WJCvnrqqAIa+Ujc/40U5vN6dn8Ls26sb26CD nj9wEuKSFHuznVag4/92i7Sy2j03bzBXbuBsBPw53NCaoRTyOWdBJHuUxlo5BaaBu6Gb yr3A== X-Gm-Message-State: AA+aEWYGiSvSFykULRalJA1QZg7U9slXUiLSgfgl5QzYF+UX9BFRoEaQ gq/YPnOXLT9xeYwlo8La9EF9qRr4ih4= X-Google-Smtp-Source: AFSGD/VUjSMkWayynn/i3gfQOL1Ra1I2mh57PZPM4ykDWAxEnQguzrWbXwRpPeYR2UCTl3qSR0K8vA== X-Received: by 2002:a19:f204:: with SMTP id q4mr30174927lfh.133.1546739479368; Sat, 05 Jan 2019 17:51:19 -0800 (PST) Received: from mail-lf1-f49.google.com (mail-lf1-f49.google.com. [209.85.167.49]) by smtp.gmail.com with ESMTPSA id z6sm12043232lfd.50.2019.01.05.17.51.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 05 Jan 2019 17:51:16 -0800 (PST) Received: by mail-lf1-f49.google.com with SMTP id i26so27882305lfc.0 for ; Sat, 05 Jan 2019 17:51:16 -0800 (PST) X-Received: by 2002:a19:6e0b:: with SMTP id j11mr30297686lfc.124.1546739475480; Sat, 05 Jan 2019 17:51:15 -0800 (PST) MIME-Version: 1.0 References: <20190106001138.GW6310@bombadil.infradead.org> In-Reply-To: From: Linus Torvalds Date: Sat, 5 Jan 2019 17:50:59 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] mm/mincore: allow for making sys_mincore() privileged To: Matthew Wilcox Cc: Jann Horn , Jiri Kosina , Andrew Morton , Greg KH , Peter Zijlstra , Michal Hocko , Linux-MM , kernel list , Linux API Content-Type: multipart/mixed; boundary="000000000000ff4c37057ec05817" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --000000000000ff4c37057ec05817 Content-Type: text/plain; charset="UTF-8" On Sat, Jan 5, 2019 at 4:22 PM Linus Torvalds wrote: > > But I think my patch to just rip out all that page lookup, and just > base it on the page table state has the fundamental advantage that it > gets rid of code. Maybe I should jst commit it, and see if anything > breaks? We do have options in case things break, and then we'd at > least know who cares (and perhaps a lot more information of _why_ they > care). Slightly updated patch in case somebody wants to try things out. Also, any comments about the pmd_trans_unstable() case? 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