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 20FE8C433EF for ; Wed, 15 Jun 2022 02:43:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345179AbiFOCno (ORCPT ); Tue, 14 Jun 2022 22:43:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242752AbiFOCnc (ORCPT ); Tue, 14 Jun 2022 22:43:32 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2792321801; Tue, 14 Jun 2022 19:43:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655261012; x=1686797012; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=9is4Wtv18iXnGG040jECVRF40gaLkbneYddeUdfg+z8=; b=UdMIFU9lH5jQcO1ZYPzBQOXXOkMCsFd76HIHUfyFTpPASyP0OcjE7oiM EWAiCyAkCFMDM/yKawlSQwhoTYkuRcBJXhueRiB8xhEl+DQh/QcRgllO+ hKNyEhKDl+WZiC0HWw9nCFeTaz7mqe2FsbnPqcdZOMbLFHHzvB4d7QI+d p9bOmhAZlYSeJgyRjESOX6+6uoQhXceTs9WrahzF72l2LfQo3KyjMfXo7 eI81r8yI7ef2Xz13sJ4xWEM7HVgAcKnVdGulJVAxg2iGn15Pvz4dCG9xl CoHzkC0deL3b7m9F8ApheZNVLcbyPjWOqWEBFAzHV5HTPy9yruAa+2J5w A==; X-IronPort-AV: E=McAfee;i="6400,9594,10378"; a="340473425" X-IronPort-AV: E=Sophos;i="5.91,300,1647327600"; d="scan'208";a="340473425" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2022 19:43:31 -0700 X-IronPort-AV: E=Sophos;i="5.91,300,1647327600"; d="scan'208";a="588834092" Received: from gao-cwp.sh.intel.com (HELO gao-cwp) ([10.239.159.23]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2022 19:43:29 -0700 Date: Wed, 15 Jun 2022 10:43:16 +0800 From: Chao Gao To: Kechen Lu Cc: kvm@vger.kernel.org, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, somduttar@nvidia.com, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v3 5/7] KVM: x86: add vCPU scoped toggling for disabled exits Message-ID: <20220615024311.GA7808@gao-cwp> References: <20220615011622.136646-1-kechenl@nvidia.com> <20220615011622.136646-6-kechenl@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220615011622.136646-6-kechenl@nvidia.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >@@ -5980,6 +5987,8 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event, > int kvm_vm_ioctl_enable_cap(struct kvm *kvm, > struct kvm_enable_cap *cap) > { >+ struct kvm_vcpu *vcpu; >+ unsigned long i; > int r; > > if (cap->flags) >@@ -6036,14 +6045,17 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, > break; > > mutex_lock(&kvm->lock); >- if (kvm->created_vcpus) >- goto disable_exits_unlock; >+ if (kvm->created_vcpus) { >+ kvm_for_each_vcpu(i, vcpu, kvm) { >+ kvm_ioctl_disable_exits(vcpu->arch, cap->args[0]); >+ static_call(kvm_x86_update_disabled_exits)(vcpu); IMO, this won't work on Intel platforms. Because, to manipulate a vCPU's VMCS, vcpu_load() should be invoked in advance to load the VMCS. Alternatively, you can add a request KVM_REQ_XXX and defer updating VMCS to the next vCPU entry. >+ } >+ } >+ mutex_unlock(&kvm->lock); > > kvm_ioctl_disable_exits(kvm->arch, cap->args[0]); > > r = 0; >-disable_exits_unlock: >- mutex_unlock(&kvm->lock); > break; > case KVM_CAP_MSR_PLATFORM_INFO: > kvm->arch.guest_can_read_msr_platform_info = cap->args[0]; >-- >2.32.0 >