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=-17.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, 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 BF42AC433E0 for ; Thu, 2 Jul 2020 16:19:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98F3520720 for ; Thu, 2 Jul 2020 16:19:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="suMZCdb6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726506AbgGBQTX (ORCPT ); Thu, 2 Jul 2020 12:19:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726300AbgGBQTW (ORCPT ); Thu, 2 Jul 2020 12:19:22 -0400 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2191BC08C5DD for ; Thu, 2 Jul 2020 09:19:22 -0700 (PDT) Received: by mail-qt1-x84a.google.com with SMTP id m25so15108590qtk.1 for ; Thu, 02 Jul 2020 09:19:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=CXTe1dgoIkziCoFVfYKeWk3MqTpTpSjmG77p0bE6NoA=; b=suMZCdb64YsbSOryl020BrcFDQ3UYPbRVImF5H5v6pc9aBeBZtiSXm2zZ/33mPrnrb WxErBfDhtBLdxno5VWInb25pAdsvuAPINvWptBxml477CQfyEGDM3UfI6YJU3GkUxAce dD2tKHU0hLlD3swE/sXOkvX4FezCBbL2CLT77TSj6dWGSLou78WiYYmFPRjE0KnZZCS9 m8R9XTNuKGncmUoCWNwAEnGp/RmNxWEICtYd5aEeoZB+zc0m1WR4/9SF/rdlNDw43VeA eJvJ4i9pIQ/aVIbIIRz0oZ+uoGCA/KjIwzJPxFewdN5NdyBvSRAONvVOOUamk+z9Sm6d cC7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=CXTe1dgoIkziCoFVfYKeWk3MqTpTpSjmG77p0bE6NoA=; b=d6FYA1Z5QjkOZznSSHDDcMefktwP9BPl2tC3AXy0Chje31fmfC1uXJGx8rm7lUFBMi VwRI3K+iDq1UUN0D9DIK09zEExBe1CTEiGgThn+KGON4iA/J2VJP1MyAuy1so+GztJHm sQvGU1ypiWsulPiJ/CqHMGDj4p78UN1BuhQ21iPKFdG9ZEZF55JGfv17gbRQ4ksrRjgw X7gODPd9yU3KVRu6UQLf1R4icSIFZjk3CcWHbCqczLFtbtA1RYU27w8wtSAvWp8QHvLX A2yT96Lz1Y6Dq98VPIxJz+Pb54mpBFw/rH7236UMPbNIakKxd54R8zvldXiwckI2SorW QYeg== X-Gm-Message-State: AOAM5305D67RomloGL6q+EOC9i/At2ppZNTcGvW7c6IpY7FAHZP2k/l+ r7lD3b4FtIKVsFxrOKZ5gQLfAvZdm4/I+U7w88ObBZShoGMuA4hriC5FPOzU23m7hv7lbBZ1wZH FWZfaOdggzracUBY7x5PisR+Fkh85S4kA03KNladQN6F7hlkxLoEtxGdXjYHtpGwrNBv9mMuCDT 0D311p X-Google-Smtp-Source: ABdhPJyMIMas8tgBt7VQOheH8xigvokD2vo4KZ/A/aw4GacYLB8/fzAlrqaYDQevZIT7u27IzMfwRvfLL/vjfnRF X-Received: by 2002:ad4:4d83:: with SMTP id cv3mr31515092qvb.236.1593706761146; Thu, 02 Jul 2020 09:19:21 -0700 (PDT) Date: Thu, 2 Jul 2020 09:19:16 -0700 Message-Id: <20200702161916.2456342-1-abhishekbh@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.27.0.212.ge8ba1cc988-goog Subject: [PATCH] x86/speculation/l1tf: Add KConfig for setting the L1D cache flush mode From: Abhishek Bhardwaj To: LKML Cc: Abhishek Bhardwaj , Anthony Steinhauser , Borislav Petkov , "H. Peter Anvin" , Ingo Molnar , Jim Mattson , Joerg Roedel , Josh Poimboeuf , Mark Gross , Paolo Bonzini , Pawan Gupta , Peter Zijlstra , Sean Christopherson , Thomas Gleixner , Tony Luck , Vitaly Kuznetsov , Waiman Long , Wanpeng Li , kvm@vger.kernel.org, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This change adds a new kernel configuration that sets the l1d cache flush setting at compile time rather than at run time. Signed-off-by: Abhishek Bhardwaj --- arch/x86/kernel/cpu/bugs.c | 8 ++++++++ arch/x86/kvm/Kconfig | 17 +++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 0b71970d2d3d2..1dcc875cf5547 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1406,7 +1406,15 @@ enum l1tf_mitigations l1tf_mitigation __ro_after_init = L1TF_MITIGATION_FLUSH; #if IS_ENABLED(CONFIG_KVM_INTEL) EXPORT_SYMBOL_GPL(l1tf_mitigation); #endif +#if (CONFIG_KVM_VMENTRY_L1D_FLUSH == 1) +enum vmx_l1d_flush_state l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NEVER; +#elif (CONFIG_KVM_VMENTRY_L1D_FLUSH == 2) +enum vmx_l1d_flush_state l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_COND; +#elif (CONFIG_KVM_VMENTRY_L1D_FLUSH == 3) +enum vmx_l1d_flush_state l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_ALWAYS; +#else enum vmx_l1d_flush_state l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO; +#endif EXPORT_SYMBOL_GPL(l1tf_vmx_mitigation); /* diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index b277a2db62676..f82a0c564e931 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -107,4 +107,21 @@ config KVM_MMU_AUDIT This option adds a R/W kVM module parameter 'mmu_audit', which allows auditing of KVM MMU events at runtime. +config KVM_VMENTRY_L1D_FLUSH + int "L1D cache flush settings (1-3)" + range 1 3 + default "2" + depends on KVM && X86 && X86_64 + help + This setting determines the L1D cache flush behavior before a VMENTER. + This is similar to setting the option / parameter to + kvm-intel.vmentry_l1d_flush. + 1 - Never flush. + 2 - Conditinally flush. + 3 - Always flush. + +# OK, it's a little counter-intuitive to do this, but it puts it neatly under +# the virtualization menu. +source "drivers/vhost/Kconfig" + endif # VIRTUALIZATION -- 2.27.0.212.ge8ba1cc988-goog