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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 D2C0FC433ED for ; Tue, 4 May 2021 21:51:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4A46613D2 for ; Tue, 4 May 2021 21:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232905AbhEDVwD (ORCPT ); Tue, 4 May 2021 17:52:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44292 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231478AbhEDVwC (ORCPT ); Tue, 4 May 2021 17:52:02 -0400 Received: from mail-pf1-x42e.google.com (mail-pf1-x42e.google.com [IPv6:2607:f8b0:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8B14C061574 for ; Tue, 4 May 2021 14:51:07 -0700 (PDT) Received: by mail-pf1-x42e.google.com with SMTP id i190so336320pfc.12 for ; Tue, 04 May 2021 14:51:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=VqtYvGK2HW/675ICBPcjqx1NTuB+M4OsXaqpSs46khM=; b=QVzEY1/U66ql90TgUkNXnanon4r1J+F8V1Gt1Z4s5/5TrMs+tD6bjJBjsnHFJrxGVR Tv0S9Sn1fBbNgOUIjsxdlfVTxK/6zGH1tetbrj8jx4/EYzbPzKav2DSWMBklIxj7KQfW /bZVW6cSqc7tV9B6ciuT5EKNmyDR4V6gzpao7w+D83KB+Kt0E8YJh8GIcK/Vc8S21uQV 95ameDL+aEyLlr7sXj7zFJtXQ1arJ1nZSBUPjyj7w0gz+a3/kDtG4RKe+s0rBjhJwm00 OhcvNYRi39aziHoPnkjAIEhP9sM3PDO9P17WlJeKHhtw2ELJNPoql9V1fPXdsgfcZNCY 4NYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=VqtYvGK2HW/675ICBPcjqx1NTuB+M4OsXaqpSs46khM=; b=PpVKFomkIFiVnLQgj21y8c1iBIgV7qmCNOzdbDEuW82m/FAHRxs6EqjcfbEfXOjjPz FF7ChcbDiYQHm7QnjUY72RAguGhJ7AezEZZXlv1ue5DGnqK2s+KlQ2WZTt66LYxWfwAD IAfFvlC4SytXkj7BzhJtXHxM0Ii9Sai9C8+wasQuc/myFLpK4jitAG6JHzy09IaKI7HO tc9Ph1rfs9XWGjn8F7+TWuJlFeuF+v3V9vEexyUdLOSMVPi4lZ6fSEXkxgbBxf4X6jTA f4Pxs99eix0zqmuXBEPORHzcOsrCKigitq7DPHmFr7yrohESzd9AdwcXS/QbLzWb35LJ NxEA== X-Gm-Message-State: AOAM532tYNJ8ptuXpO5dP2UBZLwMCP6CfZlJMLdtyCtKOjq1936DK4+l irhUjhEtfEkiw/4owtePJldSPg== X-Google-Smtp-Source: ABdhPJzkmLrLLD0/l4/t/IcaSwG83WGzyVrq8p5sXjdb/DpYBUdbDT95ew7RUGTG01LIDQmDoMPX1w== X-Received: by 2002:a17:90a:280d:: with SMTP id e13mr7873857pjd.191.1620165067168; Tue, 04 May 2021 14:51:07 -0700 (PDT) Received: from google.com (240.111.247.35.bc.googleusercontent.com. [35.247.111.240]) by smtp.gmail.com with ESMTPSA id l64sm4655029pgd.20.2021.05.04.14.51.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 May 2021 14:51:06 -0700 (PDT) Date: Tue, 4 May 2021 21:51:02 +0000 From: Sean Christopherson To: Paolo Bonzini Cc: Andy Lutomirski , Maxim Levitsky , Thomas Gleixner , Lai Jiangshan , linux-kernel@vger.kernel.org, Lai Jiangshan , Steven Rostedt , Andi Kleen , Andy Lutomirski , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Josh Poimboeuf , Uros Bizjak , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Alexandre Chartre , Juergen Gross , Joerg Roedel , Jian Cai Subject: Re: [PATCH] KVM/VMX: Invoke NMI non-IST entry instead of IST entry Message-ID: References: <38B9D60F-F24F-4910-B2DF-2A57F1060452@amacapital.net> <625057c7-ea40-4f37-8bea-cddecfe1b855@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <625057c7-ea40-4f37-8bea-cddecfe1b855@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 04, 2021, Paolo Bonzini wrote: > On 04/05/21 23:23, Andy Lutomirski wrote: > > > On May 4, 2021, at 2:21 PM, Sean Christopherson wrote: > > > FWIW, NMIs are masked if the VM-Exit was due to an NMI. > > Huh, indeed: "An NMI causes subsequent NMIs to be blocked, but only after > the VM exit completes". > > > Then this whole change is busted, since nothing will unmask NMIs. Revert it? SMI? #MC? :-) > Looks like the easiest way out indeed. I've no objection to reverting to intn, but what does reverting versus handling NMI on the kernel stack have to do with NMIs being blocked on VM-Exit due to NMI? I'm struggling mightily to connect the dots.