From patchwork Mon Feb 7 15:28:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 12737442 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 95042C433EF for ; Mon, 7 Feb 2022 15:32:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F1D5D11245D; Mon, 7 Feb 2022 15:32:12 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id BAD0111245D for ; Mon, 7 Feb 2022 15:32:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644247930; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JIz72i323mNLi2DkTwdrDXZhWqpT5EG0EiEDO8eaza0=; b=Ji5prR9uevHvD0Qk9w1JTi7MdQagAsAPNyA6AZPB6FVilzQBdlj3bsfje5hSfT8ERpxLAw C7erddFk5x50eKrAIHiiRqzgduuPVxxkD8jaF1sGnvSrHFskIHEiFCknuWBnb0iLe/gOqc rVoNwAx9t/dva6T55XAiMlYj+xNCHeA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-52-xQCvYTM7OYOhVZ8PDv0x5Q-1; Mon, 07 Feb 2022 10:32:07 -0500 X-MC-Unique: xQCvYTM7OYOhVZ8PDv0x5Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9BDDF1091DA2; Mon, 7 Feb 2022 15:32:04 +0000 (UTC) Received: from localhost.localdomain (unknown [10.40.192.15]) by smtp.corp.redhat.com (Postfix) with ESMTP id 18C485E495; Mon, 7 Feb 2022 15:31:55 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Date: Mon, 7 Feb 2022 17:28:33 +0200 Message-Id: <20220207152847.836777-17-mlevitsk@redhat.com> In-Reply-To: <20220207152847.836777-1-mlevitsk@redhat.com> References: <20220207152847.836777-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH 16/30] KVM: x86: SVM: allow to force AVIC to be enabled X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dave Hansen , Wanpeng Li , David Airlie , "Chang S. Bae" , "maintainer:X86 ARCHITECTURE 32-BIT AND 64-BIT" , "open list:X86 ARCHITECTURE 32-BIT AND 64-BIT" , Maxim Levitsky , Tony Luck , "open list:DRM DRIVERS" , Brijesh Singh , Paolo Bonzini , Vitaly Kuznetsov , Jim Mattson , "open list:INTEL GVT-g DRIVERS Intel GPU Virtualization" , "open list:INTEL DRM DRIVERS excluding Poulsbo, Moorestow..., Joerg Roedel , Borislav Petkov , Daniel Vetter , \"H. Peter Anvin\" , Ingo Molnar , Sean Christopherson , Joonas Lahtinen , Pawan Gupta , Thomas Gleixner " , Kan Liang Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Apparently on some systems AVIC is disabled in CPUID but still usable. Allow the user to override the CPUID if the user is willing to take the risk. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/svm/svm.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 85035324ed762..b88ca7f07a0fc 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -202,6 +202,9 @@ module_param(tsc_scaling, int, 0444); static bool avic; module_param(avic, bool, 0444); +static bool force_avic; +module_param_unsafe(force_avic, bool, 0444); + bool __read_mostly dump_invalid_vmcb; module_param(dump_invalid_vmcb, bool, 0644); @@ -4839,10 +4842,14 @@ static __init int svm_hardware_setup(void) nrips = false; } - enable_apicv = avic = avic && npt_enabled && boot_cpu_has(X86_FEATURE_AVIC); + enable_apicv = avic = avic && npt_enabled && (boot_cpu_has(X86_FEATURE_AVIC) || force_avic); if (enable_apicv) { - pr_info("AVIC enabled\n"); + if (!boot_cpu_has(X86_FEATURE_AVIC)) { + pr_warn("AVIC is not supported in CPUID but force enabled"); + pr_warn("Your system might crash and burn"); + } else + pr_info("AVIC enabled\n"); amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier); } else {