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,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 930D5C433F4 for ; Mon, 27 Aug 2018 19:10:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53DFB208DA for ; Mon, 27 Aug 2018 19:10:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jd+oHePZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 53DFB208DA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727226AbeH0W6b (ORCPT ); Mon, 27 Aug 2018 18:58:31 -0400 Received: from mail-pf1-f182.google.com ([209.85.210.182]:34073 "EHLO mail-pf1-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726823AbeH0W6b (ORCPT ); Mon, 27 Aug 2018 18:58:31 -0400 Received: by mail-pf1-f182.google.com with SMTP id k19-v6so30616pfi.1 for ; Mon, 27 Aug 2018 12:10:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=lENCYtMSxr4xRHwzZVa5NAUjz8pdiMzVvsTABxxgKDM=; b=jd+oHePZbrS6CEWWtibEUDac1tswd2DoK0YcpdwbygRAmMhZdcUSubzbQhFpK8fASC u1ijSM4l6CukcGXAe338aWU6XPYJ0xhr61mi+qZG1vNHq/zhS219/f8/jRbY0vjckHl5 6bLkz/neGROPlf5nSirsr0ay4ukTezoxHlpJFqLt3Hwp0Pt5qtb0l9+0eP7n9ZCIr8M1 18Yyku509QWgsUpKCLfnWR4U+EdCtNITw+XFyfrwiNw9VIffOn0gZzFGvvWjsvvCNsy9 t7biXwvDHBkTGs8BEODUSYOcv4W7Bh5jIysGXe7G2MtWm6PIwkrAP7IWKuOnoe32ruZy yXAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=lENCYtMSxr4xRHwzZVa5NAUjz8pdiMzVvsTABxxgKDM=; b=AYEh5EmTkTdVASSUJQ2EyKcK6HjwyCdR15lwo4Uenve+mceG++DEG7iLK3OMWdeDty 7dl84Jyl9rBVbIzYRcnJyQDMDCOudUY3Axvs4O+gA3senvMBg/Oh0Sq/JTLJRJ4VgWCY 4R5O1p2nRqW/DrmO/Lt73FY2YRWuqSoNjxM6Kv7QxBPKTJwZ+ok/cPq1XPxriAYA7n46 IO1jDvF6sYUvp455BLWPAarEee+F+Y/1xYQAAKftx6MUcGTkWreG3DphCXhYYRGdgrio rVwGN889ahKaHq9CTf3z0dJMAQECjN+dL7+gds8WW71z/qUih1pkUUrcDj95DuESk6cA cV8A== X-Gm-Message-State: APzg51BXOeskPvWb27SM5wqAvH/mDxZQoDvHdJhN1Z5QhN/SSR4LqSSv Mdc7Nh9POrkVFGfCXElDouw= X-Google-Smtp-Source: ANB0VdY1aTJ9/KwMorCuhgoCp4+VPGq31kd3w+0CNO7Neq61805fTpNZAI7B40ubm6O3lmB2cEtSzA== X-Received: by 2002:a62:234d:: with SMTP id j74-v6mr15394131pfj.106.1535397037818; Mon, 27 Aug 2018 12:10:37 -0700 (PDT) Received: from [10.33.114.204] ([66.170.99.1]) by smtp.gmail.com with ESMTPSA id b64-v6sm30389pfg.66.2018.08.27.12.10.36 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 Aug 2018 12:10:37 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) Subject: Re: TLB flushes on fixmap changes From: Nadav Amit In-Reply-To: Date: Mon, 27 Aug 2018 12:10:34 -0700 Cc: Masami Hiramatsu , Peter Zijlstra , Kees Cook , Linus Torvalds , Paolo Bonzini , Jiri Kosina , Will Deacon , Benjamin Herrenschmidt , Nick Piggin , the arch/x86 maintainers , Borislav Petkov , Rik van Riel , Jann Horn , Adin Scannell , Dave Hansen , Linux Kernel Mailing List , linux-mm , David Miller , Martin Schwidefsky , Michael Ellerman Content-Transfer-Encoding: quoted-printable Message-Id: <823D916E-4056-4A36-BDD8-0FB682A8DCAE@gmail.com> References: <20180824180438.GS24124@hirez.programming.kicks-ass.net> <56A9902F-44BE-4520-A17C-26650FCC3A11@gmail.com> <9A38D3F4-2F75-401D-8B4D-83A844C9061B@gmail.com> <8E0D8C66-6F21-4890-8984-B6B3082D4CC5@gmail.com> <20180826112341.f77a528763e297cbc36058fa@kernel.org> <20180826090958.GT24124@hirez.programming.kicks-ass.net> <20180827120305.01a6f26267c64610cadec5d8@kernel.org> <4BF82052-4738-441C-8763-26C85003F2C9@gmail.com> <20180827170511.6bafa15cbc102ae135366e86@kernel.org> <01DA0BDD-7504-4209-8A8F-20B27CF6A1C7@gmail.com> <0000D631-FDDF-4273-8F3C-714E6825E59B@gmail.com> To: Andy Lutomirski X-Mailer: Apple Mail (2.3445.9.1) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org at 11:58 AM, Andy Lutomirski wrote: > On Mon, Aug 27, 2018 at 11:54 AM, Nadav Amit = wrote: >>> On Mon, Aug 27, 2018 at 10:34 AM, Nadav Amit = wrote: >>> What do you all think? >>=20 >> I agree in general. But I think that current->mm would need to be = loaded, as >> otherwise I am afraid it would break switch_mm_irqs_off(). >=20 > What breaks? Actually nothing. I just saw the IBPB stuff regarding tsk, but it should = not matter.