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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham 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 D5961C433E0 for ; Sat, 16 Jan 2021 00:10:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95C7D23A5E for ; Sat, 16 Jan 2021 00:10:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728928AbhAPAJs (ORCPT ); Fri, 15 Jan 2021 19:09:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727912AbhAPAJr (ORCPT ); Fri, 15 Jan 2021 19:09:47 -0500 Received: from mail-ot1-x334.google.com (mail-ot1-x334.google.com [IPv6:2607:f8b0:4864:20::334]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9B68C061757 for ; Fri, 15 Jan 2021 16:09:06 -0800 (PST) Received: by mail-ot1-x334.google.com with SMTP id i6so10311899otr.2 for ; Fri, 15 Jan 2021 16:09:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=T96/LrmrX4v1El2ImPseDYJC7X8vCHw3ch5hAsrm1bA=; b=JgHq9YwcfkarHPYgR2P0+n7SkGpYtgtsd6SnV9KRsUnKQ+BAcHjRdpmSiHIT6lsMOL 7K1ltiSeekgfO/OdzsON8YHZEboJy8cswSlrGzH7qud3Iec4wRwuVRvKv1O37BWLMzr0 9R4/24oXo3TAAyO0VhtPA3IGx5mLPbvpEGZBsoWg7bVjdezaLKC/Bq2gC4psRNvcfz+/ pMTffgA1G7YHF1f5L4APsZlf2WpCM7Zl5Pe2yem0uoxO+kadgw49Lt7PUgIDDWHm2tlX rKZstY3UWdNJEvKlJ674kY3lf/JY3XQpoPMJ6pf7vVyUWAO/Du4rbJgfusxe/zv9vaGd 3P1w== 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; bh=T96/LrmrX4v1El2ImPseDYJC7X8vCHw3ch5hAsrm1bA=; b=nLRsjBa/PWTOfmpsbQdRpEB1kv4DBt1ITw1YCOHdUl99TTq8adHeLfXfr/JzYIrwih zC3z5kuWetN/XV/AX9m1LW6C+jaDrMmYaNiTA/tt9FG3RgiOd2wY/aOXsof3JVWJxN0R 8XLwR01Q1eZeY0qLzvWpkHqk8HNuk2MmRifyqmFii5AqONwOk2T4MURxNXfXl6KMAyH4 8IHQXZfup9lj/YOfidNNgbaysjJmN5t6KwgAIh+PzCibUPmNJ2DRRoEI0tmISVLGsKUU emVtedkkSaWBa+7fv5aOT8NaOuy1awUXDo5YCVUHlXDSXHOT/P2cxZzyEFvp3IJRfVr8 8x7g== X-Gm-Message-State: AOAM531OCEaWlvdbUQumh8oJfjcCaIKT9zRDnvn42lwruFsbURkODpYG emY2ireFjETgtaNTdGr2Qm3cUXDDdaOIqm6LcrAfrg== X-Google-Smtp-Source: ABdhPJyX5epGpS79rxarctVemmuXjNYVy1RFTLvTcq4yLzceLtn/p5JPoe5zCaa+iDP/L3UzLB9UZZRrm4vKmT6/Ky4= X-Received: by 2002:a9d:620d:: with SMTP id g13mr10334421otj.56.1610755745980; Fri, 15 Jan 2021 16:09:05 -0800 (PST) MIME-Version: 1.0 References: <20200903141122.72908-1-mgamal@redhat.com> In-Reply-To: <20200903141122.72908-1-mgamal@redhat.com> From: Jim Mattson Date: Fri, 15 Jan 2021 16:08:54 -0800 Message-ID: Subject: Re: [PATCH] KVM: x86: VMX: Make smaller physical guest address space support user-configurable To: Mohammed Gamal Cc: kvm list , Paolo Bonzini , LKML , Vitaly Kuznetsov , Wanpeng Li , Joerg Roedel , Aaron Lewis , Sean Christopherson Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 3, 2020 at 7:12 AM Mohammed Gamal wrote: > > This patch exposes allow_smaller_maxphyaddr to the user as a module parameter. > > Since smaller physical address spaces are only supported on VMX, the parameter > is only exposed in the kvm_intel module. > Modifications to VMX page fault and EPT violation handling will depend on whether > that parameter is enabled. > > Also disable support by default, and let the user decide if they want to enable > it. > > Signed-off-by: Mohammed Gamal > --- > arch/x86/kvm/vmx/vmx.c | 15 ++++++--------- > arch/x86/kvm/vmx/vmx.h | 3 +++ > arch/x86/kvm/x86.c | 2 +- > 3 files changed, 10 insertions(+), 10 deletions(-) > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index 819c185adf09..dc778c7b5a06 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -129,6 +129,9 @@ static bool __read_mostly enable_preemption_timer = 1; > module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO); > #endif > > +extern bool __read_mostly allow_smaller_maxphyaddr; Since this variable is in the kvm module rather than the kvm_intel module, its current setting is preserved across "rmmod kvm_intel; modprobe kvm_intel." That is, if set to true, it doesn't revert to false after "rmmod kvm_intel." Is that the intended behavior?