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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 779A4C433E0 for ; Tue, 9 Feb 2021 20:56:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DA8364E6B for ; Tue, 9 Feb 2021 20:56:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234178AbhBIUz7 (ORCPT ); Tue, 9 Feb 2021 15:55:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233326AbhBISvh (ORCPT ); Tue, 9 Feb 2021 13:51:37 -0500 Received: from mail-lj1-x22f.google.com (mail-lj1-x22f.google.com [IPv6:2a00:1450:4864:20::22f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5A93C0617A9 for ; Tue, 9 Feb 2021 10:40:18 -0800 (PST) Received: by mail-lj1-x22f.google.com with SMTP id f2so23710824ljp.11 for ; Tue, 09 Feb 2021 10:40:18 -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:content-transfer-encoding; bh=yrqlWhEmS7qOnCD+PpBqDD/vJX8INiaqiRYekgJQZPQ=; b=Xv5BjgLYcmU0KX+yKZtjtFg1EszFEgfnsx23ypgGzZdhfjQ2uhx0rMeCFUeL5XrtRL YO09vC7QZcYwTcu/8akG7OpWlzFlemPQkHkOCvwrfIRlH4mPHf1PL9T0mqlq5zyi1BdM 8b2RY8cyGJDx1EnZISySmVhjkPFLhbEhEex5U= 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:content-transfer-encoding; bh=yrqlWhEmS7qOnCD+PpBqDD/vJX8INiaqiRYekgJQZPQ=; b=dyzJBayIuepVrv27I/SwTaNCgAV3L6E9wt4gHg8b5qjT13xk1UezzIsIj2iinxnY9k HZQdCpNwVfoKcoHZVQX0YpdnFVkSJ+9cONierXmVUmBp7oIgeGY+kNCOZdChgODneQYC dSXmqeIscYC1r/MLxYhnwG009lHMp58vBiXAb9KH5ZqIxQUe9gHBYbIt6KnVBgO9l+0F OxPJP/7PvUk1HWtutTH1YLsIyIYjwkvKifg1W9NFglvyBlUwv3VH0AyQXngWYKxsHdTA Ck5HORS7KwA9DlfzMot1QGendL8oqAx23dF/TL6883SbTl/K7oLhOXLYi0+Whpp81chb y1Zg== X-Gm-Message-State: AOAM532Su6u9i0W2ZbhEGlftYul3Y5ycAudoVHVuN9yDNlyTv1f4DmCP eTTccJPOMYKAvLK3pbW4IFsD2hco+YKUYw== X-Google-Smtp-Source: ABdhPJwJP+3y8hFX+saTf30ixefXliKSRn8XjPpbu+sczQW/1JUvBJJjGf6Wo/AnYNId2YpltLoFQQ== X-Received: by 2002:a2e:96c6:: with SMTP id d6mr15319654ljj.273.1612896016843; Tue, 09 Feb 2021 10:40:16 -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 p16sm2647674lfc.97.2021.02.09.10.40.15 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 09 Feb 2021 10:40:15 -0800 (PST) Received: by mail-lj1-f170.google.com with SMTP id f8so14029505ljk.3 for ; Tue, 09 Feb 2021 10:40:15 -0800 (PST) X-Received: by 2002:a2e:b70b:: with SMTP id j11mr14786681ljo.61.1612896014711; Tue, 09 Feb 2021 10:40:14 -0800 (PST) MIME-Version: 1.0 References: <3C17D187-8691-4521-9B64-F42A0B514F13@amacapital.net> In-Reply-To: <3C17D187-8691-4521-9B64-F42A0B514F13@amacapital.net> From: Linus Torvalds Date: Tue, 9 Feb 2021 10:39:58 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [GIT PULL] x86/urgent for v5.11-rc7 To: Andy Lutomirski Cc: Alexei Starovoitov , Steven Rostedt , Miroslav Benes , Peter Zijlstra , Josh Poimboeuf , Borislav Petkov , Dave Hansen , x86-ml , lkml , Alexei Starovoitov , live-patching@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 9, 2021 at 10:26 AM Andy Lutomirski wrote= : > > > > Anything else would just be insanely complicated, I feel. > > The other model is =E2=80=9Cdon=E2=80=99t do that then.=E2=80=9D Hmm. I guess all the code that does int3 patching could just be taught to always go to the next instruction instead. I don't think advancing the rewriting is an option for the asm alternative() logic or the static call infrastructure, but those should never be about endbr anyway, so presumably that's not an issue. So if it ends up being _only_ about kprobes, then the "don't do that then" might work fine. Linus