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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, 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 E15EDC34031 for ; Tue, 18 Feb 2020 23:11:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5C5324655 for ; Tue, 18 Feb 2020 23:11:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=amacapital-net.20150623.gappssmtp.com header.i=@amacapital-net.20150623.gappssmtp.com header.b="XZenJzgM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727849AbgBRXL4 (ORCPT ); Tue, 18 Feb 2020 18:11:56 -0500 Received: from mail-pg1-f182.google.com ([209.85.215.182]:37214 "EHLO mail-pg1-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727553AbgBRXLz (ORCPT ); Tue, 18 Feb 2020 18:11:55 -0500 Received: by mail-pg1-f182.google.com with SMTP id z12so11720818pgl.4 for ; Tue, 18 Feb 2020 15:11:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amacapital-net.20150623.gappssmtp.com; s=20150623; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=DXk+4RCbn43nqyIHGgTQFY5EAVuHQEITLuF0Eerk39Q=; b=XZenJzgMpinXndb3Ft4G15TfderKPHgDYRxpubwasNQLkZB+Ej7R/UFEF15vdnY9y4 knD7v9XCGz7RiZzDop4DPV2KOyHwLl2olZtj5k4OEp1FCOpvdxk+9um/fK5aCrlgg4I3 PG+3JJr57m6oGVFFXkqnu4GTFYrTXok91wMb4hIhi09OIE0d9E/anDmZJbts186Pr0BI QIcVz41u97YuL94xKs5o8oQv22Ne16wb56FisvA82LkFUCqlZha+3goWyrX9J/hCRZ/z v0vLEiTg3Lnd7R67bGrnQ7TeA7ONNqzDUmWutK39lOikG9jz2SwbcC6tvZeIduhnNlZq B8uQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=DXk+4RCbn43nqyIHGgTQFY5EAVuHQEITLuF0Eerk39Q=; b=hCf9y0qv/yho/r1P/Mg0dTjy/7BGTEjWndT9s3pNbBjfc3MydBk6nNYaHuRgjqgkJv qPN41kILmYL8PpgWnnPs+uBIi5igE7K3AnlRrG567QhXyVGrCvfdWdWD9bt5Wjvsa7Gz +vxoILYCQ0x0fEh/9Zb8juf/SZCp7lnoiyDW5ymvw8jaP5xk46m6D4FHlyXFT3ChA1hw Q4vGZdzHarBaVBsYo7snR4GprPAOxEZqaEZX8mANGItaebqsRn25O8efl0Pw9c8PG05l XISCsertXxrfdeRpPPUsuCXjGLWru4qhWAl8RqglGbJYbMsqOjaGZE4R4Jx4M8h6s7WP le3w== X-Gm-Message-State: APjAAAWIRAKZfg1Wy11hliZbVnWFPrROcZqxT0FN2FmqE75sugXRKpXG rs3WQleiGpBRfBXBBXs7/61+0w== X-Google-Smtp-Source: APXvYqxAvYc6wOp++1fA29CqVZ4pX8ZcQgO5sfXyrjNUJqM3cKhZrGBDX4l7ssoxrYcvkA1KbymPQQ== X-Received: by 2002:aa7:968c:: with SMTP id f12mr23710431pfk.235.1582067515244; Tue, 18 Feb 2020 15:11:55 -0800 (PST) Received: from [10.234.160.59] (58.sub-97-41-129.myvzw.com. [97.41.129.58]) by smtp.gmail.com with ESMTPSA id p17sm76321pfn.31.2020.02.18.15.11.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 18 Feb 2020 15:11:54 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Andy Lutomirski Mime-Version: 1.0 (1.0) Subject: Re: [RFC] #MC mess Date: Tue, 18 Feb 2020 15:10:17 -0800 Message-Id: <3CF4895A-5BCF-4E5C-B8D9-F9019DD02A12@amacapital.net> References: <3908561D78D1C84285E8C5FCA982C28F7F57B937@ORSMSX115.amr.corp.intel.com> Cc: Borislav Petkov , Peter Zijlstra , Steven Rostedt , Andy Lutomirski , x86-ml , lkml In-Reply-To: <3908561D78D1C84285E8C5FCA982C28F7F57B937@ORSMSX115.amr.corp.intel.com> To: "Luck, Tony" X-Mailer: iPhone Mail (17D50) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Feb 18, 2020, at 10:20 AM, Luck, Tony wrote: >=20 > =EF=BB=BF >>=20 >> Anything else I'm missing? It is likely... >=20 > + hw_breakpoint_disable(); > + static_key_disable(&__tracepoint_read_msr.key); > + tracing_off(); > + > ist_enter(regs); >=20 > How about some code to turn all those back on for a recoverable (where we a= ctually recovered) #MC? >=20 >=20 At the very least, in the user_mode(regs) case, tracing is fine.=