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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 23780C433DF for ; Tue, 23 Jun 2020 16:14:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EBC492076E for ; Tue, 23 Jun 2020 16:14:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="AR8Cmxfv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732533AbgFWQOA (ORCPT ); Tue, 23 Jun 2020 12:14:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728916AbgFWQOA (ORCPT ); Tue, 23 Jun 2020 12:14:00 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB55CC061573; Tue, 23 Jun 2020 09:13:59 -0700 (PDT) Received: from zn.tnic (p200300ec2f0d47007938aef930b6c4fb.dip0.t-ipconnect.de [IPv6:2003:ec:2f0d:4700:7938:aef9:30b6:c4fb]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 768C01EC0318; Tue, 23 Jun 2020 18:13:58 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1592928838; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=3hydVVgqDlrgbEgBTFy7VUDI9fCz0nmR1nF+TA1bYQw=; b=AR8Cmxfvj2g5TZiJF22qVNjyxrjEzi3qfokFyvjRPZq+FHX1ONnQ12Y6ioP86xvNIHjtpg gOafUnBClkDXUL9gFcNJbChJb5NJxzTl5Zu/LFrlT4AOc2DvxW0JNlKjsJmB/sKD0V4kPs hmqNU/N1ePn0BbF1IV0jxu/Bj1GQ9R0= Date: Tue, 23 Jun 2020 18:13:55 +0200 From: Borislav Petkov To: Andrew Cooper Cc: Peter Zijlstra , Joerg Roedel , Andy Lutomirski , Joerg Roedel , Dave Hansen , Tom Lendacky , Mike Stunes , Dan Williams , Dave Hansen , "H. Peter Anvin" , Juergen Gross , Jiri Slaby , Kees Cook , kvm list , LKML , Thomas Hellstrom , Linux Virtualization , X86 ML , Sean Christopherson Subject: Re: Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace) Message-ID: <20200623161355.GF32590@zn.tnic> References: <20200623113007.GH31822@suse.de> <20200623114818.GD4817@hirez.programming.kicks-ass.net> <20200623120433.GB14101@suse.de> <20200623125201.GG4817@hirez.programming.kicks-ass.net> <20200623134003.GD14101@suse.de> <20200623135916.GI4817@hirez.programming.kicks-ass.net> <20200623145344.GA117543@hirez.programming.kicks-ass.net> <20200623145914.GF14101@suse.de> <20200623152326.GL4817@hirez.programming.kicks-ass.net> <56af2f70-a1c6-aa64-006e-23f2f3880887@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <56af2f70-a1c6-aa64-006e-23f2f3880887@citrix.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Jun 23, 2020 at 04:39:26PM +0100, Andrew Cooper wrote: > P.S. did you also hear that with Rowhammer, userspace has a nonzero > quantity of control over generating #MC, depending on how ECC is > configured on the platform. Where does that #MC point to? Can it control for which address to flip the bits for, i.e., make the #MC appear it has been generated for an address in kernel space? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette