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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9AC1CDB482 for ; Wed, 18 Oct 2023 19:41:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231687AbjJRTlQ (ORCPT ); Wed, 18 Oct 2023 15:41:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231618AbjJRTlN (ORCPT ); Wed, 18 Oct 2023 15:41:13 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04CB0AB for ; Wed, 18 Oct 2023 12:41:12 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d9b9f56489fso5652390276.1 for ; Wed, 18 Oct 2023 12:41:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1697658071; x=1698262871; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=Ofuuq8OnXnBwuNBiWtVLb1NEzqrH7XwtOSMnrh73sd8=; b=KQUyfewpiZDgHKhuBlxHffQ0dmFuq14bplh/X97tRzsZ1J4IVFw9LgSRusq4uePP7p I2fWrJB20gGOcn5OK3sPVx1Cws82eApx0yayMcRBTHMuag8ieLn/2rpiqGl3vYU4HPMP plDRDLUy8748Fghanx4KRrDiuZHDMRky8F4wOa8TUtlosUPPrnt8TW2Km2mHMOe1rfJT aNFAX76iUsrGF5vygVrg4yh/zpC/grDHqg9iEFeZfNT7U1Y0o/YXZDFBZvUTTCpBtV2t ZuO/MR0PUS/H22Pu5+Tp47+t0h+q8nJwrIqvaJ1iEY8W14kWB6immkZlwC+AABSEmehm PINg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697658071; x=1698262871; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Ofuuq8OnXnBwuNBiWtVLb1NEzqrH7XwtOSMnrh73sd8=; b=PRKOH9ukV0504k3WI3r5SlfLGfVm82eEZ4pTlrpl5fslNdMiMGeJKI2kR9ZsxbpspA I8zbevtlGYr9cejldEP/NXQrpJHYdYq5+z4hbX0TpgN1gsqtaB+bfIdgfaZrtIC/9J8q Zz2gxD22tWbH447cWBXOg7mbCQgUH6i7v7fb61NhunwJp/JaQYpvywocuJgC+qpAIyAb 60/ocboslsYSAeK7ZOCMyFvIuHewOlMQXU/CEqdRkkncudsHLfAuDUjT7nOsd5yLSf4G 1HG2GsBZbPwwISbxgTKzXXWTLvnvO6uUWHN390MlhJPN1mwe9ImoFVEqwFLWAHcx2bWK KkVw== X-Gm-Message-State: AOJu0YwUC5fcFU1ZKg1cEZi4qAu9xvPY21wVqWWBVSoiH387g7Pka7R8 WaDiZeyCiL3gUQq4R6lipzt4qD1yzHo= X-Google-Smtp-Source: AGHT+IGW0vvt2l55+JL2+bM3VOgMoxB7qvHv720MxhQbccRQ4nqpX0a4NV57+RPdy39vplncxaNMVHs5grk= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6902:1825:b0:d9a:d272:ee58 with SMTP id cf37-20020a056902182500b00d9ad272ee58mr7884ybb.9.1697658071068; Wed, 18 Oct 2023 12:41:11 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 18 Oct 2023 12:41:04 -0700 In-Reply-To: <20231018194104.1896415-1-seanjc@google.com> Mime-Version: 1.0 References: <20231018194104.1896415-1-seanjc@google.com> X-Mailer: git-send-email 2.42.0.655.g421f12c284-goog Message-ID: <20231018194104.1896415-3-seanjc@google.com> Subject: [PATCH 2/2] KVM: nSVM: Advertise support for flush-by-ASID From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Sterz Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Advertise support for FLUSHBYASID when nested SVM is enabled, as KVM can always emulate flushing TLB entries for a vmcb12 ASID, e.g. by running L2 with a new, fresh ASID in vmcb02. Some modern hypervisors, e.g. VMWare Workstation 17, require FLUSHBYASID support and will refuse to run if it's not present. Punt on proper support, as "Honor L1's request to flush an ASID on nested VMRUN" is one of the TODO items in the (incomplete) list of issues that need to be addressed in order for KVM to NOT do a full TLB flush on every nested SVM transition (see nested_svm_transition_tlb_flush()). Reported-by: Stefan Sterz Closes: https://lkml.kernel.org/r/b9915c9c-4cf6-051a-2d91-44cc6380f455%40proxmox.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 1785de7dc98b..9cf7eef161ff 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -5083,6 +5083,7 @@ static __init void svm_set_cpu_caps(void) if (nested) { kvm_cpu_cap_set(X86_FEATURE_SVM); kvm_cpu_cap_set(X86_FEATURE_VMCBCLEAN); + kvm_cpu_cap_set(X86_FEATURE_FLUSHBYASID); if (nrips) kvm_cpu_cap_set(X86_FEATURE_NRIPS); -- 2.42.0.655.g421f12c284-goog