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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS autolearn=unavailable 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 0AFAAC10F03 for ; Tue, 23 Apr 2019 16:26:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C964F208E4 for ; Tue, 23 Apr 2019 16:26:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556036802; bh=2OT9KGiqC+6zd5kn44Txotwu4I0Uuogn1Ev4NEa7fQ4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=LvPtjcXAVzUp1IWZE79sAj0eT7EbKMMHUyj9RUgg99SUrdMWupyuRCNPIE3/cYpJT U1Yjn2OCBL/mG+u4BYeRvvoYyhoHGSTeZF8l03hkRwyOLC1dpk2fn38XnnARMCX0gw qb5KG3/ZrtXslDhz3pAoBcKvbHltXLpFrM+LZxXg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727754AbfDWQ0m (ORCPT ); Tue, 23 Apr 2019 12:26:42 -0400 Received: from mail-lf1-f67.google.com ([209.85.167.67]:46135 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727666AbfDWQ0l (ORCPT ); Tue, 23 Apr 2019 12:26:41 -0400 Received: by mail-lf1-f67.google.com with SMTP id k18so12224383lfj.13 for ; Tue, 23 Apr 2019 09:26:40 -0700 (PDT) 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=9lZI3PImqx3T4CK/0DFoAjfnTtOk7dOVBphM/XkSKVI=; b=U0ZAOGTH5UzOQdSVmsRebl4caZMqgVo2nPoPpTPrrdJ2jTA2RW3NvPCtg1KZ42Zvcn G1ZGbbk7dpA34xaZlDxhRhMjPICHO6n25H8k2Y6VQo012xfUtNyPqEP4sg7Co05cV8zT 6xNAONXbiweJJlYFDC8Lw3jO/2/rX7GIsZO6s= 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=9lZI3PImqx3T4CK/0DFoAjfnTtOk7dOVBphM/XkSKVI=; b=IwBFLYJaoxyyMICOrUUEfQgrFgV3L4l3ijJsKPNYXa9YCUFzWdZBV+/cbGztSxQEkd QDD+hef27fBsJj8/8vk47rpRY+VrQD+5w7IeqYsx4tNK1uI8iDxQIiodQLKJnTUlwZMd rthoImyuobL7TuVLGzMFNxKmJTMUg3k6a9yvgjzfVyGfUZUsV1BdhJOGJ81WWiFBzHfp 6ZnxJiVqhErN9A4z+Niq9sEy5XZThfa6mtnxTiDz2QubVprsJgzBAKIQXUb7Ae5rY4mz swMjrGvTkbfeaZA/+2C7FKWc0ybURuTjCOdcBU2PgACilJOGIm2SuvYHez6eqRGy0/PN NiPQ== X-Gm-Message-State: APjAAAX3XDUgexMAmo8OTXLevJa9L4IqZmrND9zMjq1jYqdtgyeJ9wUQ b110ZT57EkfvGCH+Xmhv8co25MNaeS0= X-Google-Smtp-Source: APXvYqw5NoDZUs62LL3QOTCBX4BTb8yWocH8Alq5lWfzkvKd4sgeBTP+txzjTWIIC/MwcCeOVmi3Ig== X-Received: by 2002:a19:428c:: with SMTP id p134mr15102819lfa.108.1556036799484; Tue, 23 Apr 2019 09:26:39 -0700 (PDT) Received: from mail-lj1-f172.google.com (mail-lj1-f172.google.com. [209.85.208.172]) by smtp.gmail.com with ESMTPSA id s67sm3486599lja.57.2019.04.23.09.26.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 23 Apr 2019 09:26:39 -0700 (PDT) Received: by mail-lj1-f172.google.com with SMTP id l23so3508671lja.3 for ; Tue, 23 Apr 2019 09:26:38 -0700 (PDT) X-Received: by 2002:a2e:5dd2:: with SMTP id v79mr14738625lje.22.1556036406473; Tue, 23 Apr 2019 09:20:06 -0700 (PDT) MIME-Version: 1.0 References: <20190419215358.WMVFXV3bT%akpm@linux-foundation.org> <20190423082448.GY11158@hirez.programming.kicks-ass.net> In-Reply-To: <20190423082448.GY11158@hirez.programming.kicks-ass.net> From: Linus Torvalds Date: Tue, 23 Apr 2019 09:19:50 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: mmotm 2019-04-19-14-53 uploaded (objtool) To: Peter Zijlstra Cc: Randy Dunlap , Andrew Morton , Mark Brown , linux-fsdevel , Linux List Kernel Mailing , Linux-MM , linux-next@vger.kernel.org, mhocko@suse.cz, mm-commits@vger.kernel.org, Stephen Rothwell , Josh Poimboeuf , Andy Lutomirski Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Apr 23, 2019 at 1:25 AM Peter Zijlstra wrote: > > Now, we could of course allow this symbol, but I found only the below > was required to make allyesconfig build without issue. > > Andy, Linus? Ack on that patch. Except I think the uaccess.h part should be a separate commit: I think it goes along with 2a418cf3f5f1 ("x86/uaccess: Don't leak the AC flag into __put_user() value evaluation") we did earlier. I think the logic is the same - it's not just the _value_ that can have complex calculations, the address can too (although admittedly that's really not supposed to be common, but you clearly found one case where a complier misfeature made it happen, so...). I also wonder if we should just make "count" be "unsigned long" in do_{strncpy_from,strnlen}_user() too, since we've already done if (unlikely(count <= 0)) return 0; in the caller, so it *is* unsigned by then, and we'd not be mixing signedness when comparing "max/count/res". Linus