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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,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 CEF61C433B4 for ; Tue, 4 May 2021 23:37:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5CCB613C1 for ; Tue, 4 May 2021 23:37:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231447AbhEDXh4 (ORCPT ); Tue, 4 May 2021 19:37:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39246 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231430AbhEDXhy (ORCPT ); Tue, 4 May 2021 19:37:54 -0400 Received: from mail-oi1-x232.google.com (mail-oi1-x232.google.com [IPv6:2607:f8b0:4864:20::232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4EEFC061574 for ; Tue, 4 May 2021 16:36:58 -0700 (PDT) Received: by mail-oi1-x232.google.com with SMTP id t8so583098oij.0 for ; Tue, 04 May 2021 16:36:58 -0700 (PDT) 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=7ZG1nWXtzTYTaXrMK1FVDEfdYcnwUzz0W/Bp4Vm63w8=; b=W0/NtpO49BkFw56cUrtxd4cEfAJIY00IrrdCRRM83zOAeUgsB5GNY/mRrQ9guQ+GCu zt+IJvmorwCO7B/VnqnHGwHqgBURRJbU4N9fAgchjHtd3fM8mwQ3UelDSkOAA8+3qMf8 r9JZMox/04J0poAyl2fdpSvJp4JNeW+aKECRZEie7GHgopXF8ef5KvuID8N/VIJ3vacw /pAZnyCOMa76HYaURuL4TrKT5xRQmbHMuP/59JFIL5CjKdSjWfNmpOhrGkgBJEeFKtJR 3qFalKYZueX64+3yV8ur8yG1/8AgITMp2LXEsXIZN2c/2iR9N87REuOR7ayWiX89ltLq MGAg== 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=7ZG1nWXtzTYTaXrMK1FVDEfdYcnwUzz0W/Bp4Vm63w8=; b=CF5BsgFLHh0TrrA3OSeMyAz+4j+9NQCInh0TsxLcdDMoPYrAtpV1lO1wXwv0OEh4i6 zbJxxMQ/VybgHt6gLPFsSE0BZ4R5BAkG8qb1oa+3t+JeXDPN0pDisqE7adsKWwlccHxV oo/88maF7V7wGVqyRJkkUdHmbr1TSjyFTTBlBi3Wn1ANfnTOzX4+Pdc3VZqH+NPloKXl XD6ubWhhdGq8700GTfA8+E//4bzbw4EEjMcfQZzyR2gH80pHSmcSmNv8ekuXb38TdAnG 8FHrAIx7X8+w31/6QI7Oyfe9Ewxx/3c2i5uRB/NPGLIUEtSpv+demubulo+YlxL5IOpk vt0A== X-Gm-Message-State: AOAM533C5s9z62w4eSX7STwJRtyCIH78Fd3sRqUgfsa/e7vSBYAIRQMW DtmyW2n5hu3Bl619dz4GqLXsW7vTbU8Vwm57QgirCg== X-Google-Smtp-Source: ABdhPJwn/nngurgnvemnAXyxfhI7q1jjWsE5Plk4Zrimr9wx7e+kViDLlODMMe3olSMzacxI1V8LVMwEjPJKagGUspg= X-Received: by 2002:a05:6808:b2f:: with SMTP id t15mr4766153oij.6.1620171418015; Tue, 04 May 2021 16:36:58 -0700 (PDT) MIME-Version: 1.0 References: <20210504171734.1434054-1-seanjc@google.com> <20210504171734.1434054-6-seanjc@google.com> In-Reply-To: <20210504171734.1434054-6-seanjc@google.com> From: Jim Mattson Date: Tue, 4 May 2021 16:36:46 -0700 Message-ID: Subject: Re: [PATCH 05/15] KVM: VMX: Disable preemption when probing user return MSRs To: Sean Christopherson Cc: Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Joerg Roedel , kvm list , LKML , Xiaoyao Li , Reiji Watanabe Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 4, 2021 at 10:17 AM Sean Christopherson wrote: > > Disable preemption when probing a user return MSR via RDSMR/WRMSR. If > the MSR holds a different value per logical CPU, the WRMSR could corrupt > the host's value if KVM is preempted between the RDMSR and WRMSR, and > then rescheduled on a different CPU. > > Opportunistically land the helper in common x86, SVM will use the helper > in a future commit. > > Fixes: 4be534102624 ("KVM: VMX: Initialize vmx->guest_msrs[] right after allocation") > Cc: stable@vger.kernel.org > Cc: Xiaoyao Li > Signed-off-by: Sean Christopherson Reviewed-by: Jim Mattson