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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 C9DDAC433E1 for ; Fri, 24 Jul 2020 17:42:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A86932067D for ; Fri, 24 Jul 2020 17:42:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="WU9slZt/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726821AbgGXRmW (ORCPT ); Fri, 24 Jul 2020 13:42:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726397AbgGXRmW (ORCPT ); Fri, 24 Jul 2020 13:42:22 -0400 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DBC5C0619E4 for ; Fri, 24 Jul 2020 10:42:22 -0700 (PDT) Received: by mail-pl1-x642.google.com with SMTP id m16so4878492pls.5 for ; Fri, 24 Jul 2020 10:42:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=XwpNl/RSgSBBWaddv3urfADovlU2IQQNUsOQ5gJRgfo=; b=WU9slZt/60VXkdmS1OpvEXJ8mEGSsVlwVeByIAqKlB/4k4px26WInz/NJ5KOpt9C7f 71G2bwjhucwf/lZMokI1XX2uVD8KUgvc/COEJEVz2m64NkyoZ/IbSDZCGM/fR83z0Ctk /0825/9u+PETjTUByM40o6Ma8MVukMZWFS+Ms= 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=XwpNl/RSgSBBWaddv3urfADovlU2IQQNUsOQ5gJRgfo=; b=YV6z/mevLPYLtTPOqYCmvbRl7vIQC1Qda/VaoZv3xorY76IfJsQbW81tsCOnJUFWGA 2/QpaX2brPxvH2V6Rx8+/X/1a8zsq52LOZ7cHD37b5jV7cBgdDkFX9UsSeNhaeDb/9hL DOs4bbRbgldKL2Lo9hpeefVeVVRrhCnz+w3sN9mp5HA7Qko0e0f6LmxzgEseKqju1bPK Y6WYJyJ42eWZ2+EOFz2srXP9/U0DCsN/5RPcpVUZckN0dmG7Guqy96cNy6ZbhizmoV2M qwlUcnwNcMNqK4DlrR/n+Hkmpb7FbcyM3Ko2mtwZUsYNggi2dfaENvdORcQt2aC+1RC4 Q2kw== X-Gm-Message-State: AOAM530EpeHJqZgNpsVt2r9Gn8Z8AN+KMalvZJnuLxVstYV3t5SatS41 /wx4/TPpfS6ARbzLmZPTMma2LQ== X-Google-Smtp-Source: ABdhPJzuAMEgACl6KnJ/cKznCSDX4BZLn6+ziD98Tx6G4Jv3sBo+cq7KrfZKMmeGTt0N9+kxSsv5rA== X-Received: by 2002:a17:90b:1812:: with SMTP id lw18mr208834pjb.70.1595612541740; Fri, 24 Jul 2020 10:42:21 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id p11sm6540646pfq.91.2020.07.24.10.42.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jul 2020 10:42:20 -0700 (PDT) Date: Fri, 24 Jul 2020 10:42:20 -0700 From: Kees Cook To: Joerg Roedel Cc: x86@kernel.org, Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: Re: [PATCH v5 30/75] x86/head/64: Setup MSR_GS_BASE before calling into C code Message-ID: <202007241041.71B4B3E@keescook> References: <20200724160336.5435-1-joro@8bytes.org> <20200724160336.5435-31-joro@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200724160336.5435-31-joro@8bytes.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Jul 24, 2020 at 06:02:51PM +0200, Joerg Roedel wrote: > From: Joerg Roedel > > When stack-protector is enabled a valid GS_BASE is needed before > calling any C code function, because the stack canary is loaded from > per-cpu data. > > Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook -- Kees Cook