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 3A78EC433F5 for ; Wed, 18 May 2022 12:49:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236832AbiERMtv (ORCPT ); Wed, 18 May 2022 08:49:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236776AbiERMtu (ORCPT ); Wed, 18 May 2022 08:49:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C2DE618DADC for ; Wed, 18 May 2022 05:49:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652878186; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ud+EoewnZynIABdLMtBZtAj7r2i0k69OeMeQkGeRK8k=; b=FerM3AaQf4sOabJ6AbxkBUzVic7OrT3xI5qr0rc2RHclIwOMF+929wSHNzNcTwDSLKSWrj iipYnDh9jPGoEhPJk31dKHSQZNXlIPOQNFI9WVvgrMCKF/UBtVIMXTUOGLsRfACNUqgzDl ahK9HPAtBBQBo+mGnuik0/8/xqyXiH8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-449-y84T1USJP3O-JM7cwBbXYA-1; Wed, 18 May 2022 08:49:43 -0400 X-MC-Unique: y84T1USJP3O-JM7cwBbXYA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0C1C429DD9B4; Wed, 18 May 2022 12:49:43 +0000 (UTC) Received: from starship (unknown [10.40.192.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id C65C42026D6A; Wed, 18 May 2022 12:49:40 +0000 (UTC) Message-ID: <57aa037a77ba8d8e182d8c77233c5954dd2fa2d9.camel@redhat.com> Subject: Re: [PATCH v3 14/34] KVM: x86: Introduce .post_hv_l2_tlb_flush() nested hook From: Maxim Levitsky To: Vitaly Kuznetsov Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Michael Kelley , Siddharth Chandrasekaran , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini Date: Wed, 18 May 2022 15:49:39 +0300 In-Reply-To: <871qwrui3o.fsf@redhat.com> References: <20220414132013.1588929-1-vkuznets@redhat.com> <20220414132013.1588929-15-vkuznets@redhat.com> <871qwrui3o.fsf@redhat.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-2.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Wed, 2022-05-18 at 14:43 +0200, Vitaly Kuznetsov wrote: > Maxim Levitsky writes: > > > On Thu, 2022-04-14 at 15:19 +0200, Vitaly Kuznetsov wrote: > > > Hyper-V supports injecting synthetic L2->L1 exit after performing > > > L2 TLB flush operation but the procedure is vendor specific. > > > Introduce .post_hv_l2_tlb_flush() nested hook for it. > > > > > > Signed-off-by: Vitaly Kuznetsov > > > --- > > > arch/x86/include/asm/kvm_host.h | 1 + > > > arch/x86/kvm/Makefile | 3 ++- > > > arch/x86/kvm/svm/hyperv.c | 11 +++++++++++ > > > arch/x86/kvm/svm/hyperv.h | 2 ++ > > > arch/x86/kvm/svm/nested.c | 1 + > > > arch/x86/kvm/vmx/evmcs.c | 4 ++++ > > > arch/x86/kvm/vmx/evmcs.h | 1 + > > > arch/x86/kvm/vmx/nested.c | 1 + > > > 8 files changed, 23 insertions(+), 1 deletion(-) > > > create mode 100644 arch/x86/kvm/svm/hyperv.c > > > > > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > > > index 8b2a52bf26c0..ce62fde5f4ff 100644 > > > --- a/arch/x86/include/asm/kvm_host.h > > > +++ b/arch/x86/include/asm/kvm_host.h > > > @@ -1558,6 +1558,7 @@ struct kvm_x86_nested_ops { > > > int (*enable_evmcs)(struct kvm_vcpu *vcpu, > > > uint16_t *vmcs_version); > > > uint16_t (*get_evmcs_version)(struct kvm_vcpu *vcpu); > > > + void (*post_hv_l2_tlb_flush)(struct kvm_vcpu *vcpu); > > > }; > > > > > > struct kvm_x86_init_ops { > > > diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile > > > index 30f244b64523..b6d53b045692 100644 > > > --- a/arch/x86/kvm/Makefile > > > +++ b/arch/x86/kvm/Makefile > > > @@ -25,7 +25,8 @@ kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \ > > > vmx/evmcs.o vmx/nested.o vmx/posted_intr.o > > > kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o > > > > > > -kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o svm/sev.o > > > +kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \ > > > + svm/sev.o svm/hyperv.o > > > > > > ifdef CONFIG_HYPERV > > > kvm-amd-y += svm/svm_onhyperv.o > > > diff --git a/arch/x86/kvm/svm/hyperv.c b/arch/x86/kvm/svm/hyperv.c > > > new file mode 100644 > > > index 000000000000..c0749fc282fe > > > --- /dev/null > > > +++ b/arch/x86/kvm/svm/hyperv.c > > > @@ -0,0 +1,11 @@ > > > +// SPDX-License-Identifier: GPL-2.0-only > > > +/* > > > + * AMD SVM specific code for Hyper-V on KVM. > > > + * > > > + * Copyright 2022 Red Hat, Inc. and/or its affiliates. > > > + */ > > > +#include "hyperv.h" > > > + > > > +void svm_post_hv_l2_tlb_flush(struct kvm_vcpu *vcpu) > > > +{ > > > +} > > > diff --git a/arch/x86/kvm/svm/hyperv.h b/arch/x86/kvm/svm/hyperv.h > > > index 8cf702fed7e5..a2b0d7580b0d 100644 > > > --- a/arch/x86/kvm/svm/hyperv.h > > > +++ b/arch/x86/kvm/svm/hyperv.h > > > @@ -48,4 +48,6 @@ static inline void nested_svm_hv_update_vm_vp_ids(struct kvm_vcpu *vcpu) > > > hv_vcpu->nested.vp_id = hve->hv_vp_id; > > > } > > > > > > +void svm_post_hv_l2_tlb_flush(struct kvm_vcpu *vcpu); > > > + > > > #endif /* __ARCH_X86_KVM_SVM_HYPERV_H__ */ > > > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c > > > index 2d1a76343404..de3f27301b5c 100644 > > > --- a/arch/x86/kvm/svm/nested.c > > > +++ b/arch/x86/kvm/svm/nested.c > > > @@ -1665,4 +1665,5 @@ struct kvm_x86_nested_ops svm_nested_ops = { > > > .get_nested_state_pages = svm_get_nested_state_pages, > > > .get_state = svm_get_nested_state, > > > .set_state = svm_set_nested_state, > > > + .post_hv_l2_tlb_flush = svm_post_hv_l2_tlb_flush, > > > }; > > > diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c > > > index 87e3dc10edf4..e390e67496df 100644 > > > --- a/arch/x86/kvm/vmx/evmcs.c > > > +++ b/arch/x86/kvm/vmx/evmcs.c > > > @@ -437,3 +437,7 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu, > > > > > > return 0; > > > } > > > + > > > +void vmx_post_hv_l2_tlb_flush(struct kvm_vcpu *vcpu) > > > +{ > > > +} > > > diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h > > > index 8d70f9aea94b..b120b0ead4f3 100644 > > > --- a/arch/x86/kvm/vmx/evmcs.h > > > +++ b/arch/x86/kvm/vmx/evmcs.h > > > @@ -244,5 +244,6 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu, > > > uint16_t *vmcs_version); > > > void nested_evmcs_filter_control_msr(u32 msr_index, u64 *pdata); > > > int nested_evmcs_check_controls(struct vmcs12 *vmcs12); > > > +void vmx_post_hv_l2_tlb_flush(struct kvm_vcpu *vcpu); > > > > > > #endif /* __KVM_X86_VMX_EVMCS_H */ > > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > > > index ee88921c6156..cc6c944b5815 100644 > > > --- a/arch/x86/kvm/vmx/nested.c > > > +++ b/arch/x86/kvm/vmx/nested.c > > > @@ -6850,4 +6850,5 @@ struct kvm_x86_nested_ops vmx_nested_ops = { > > > .write_log_dirty = nested_vmx_write_pml_buffer, > > > .enable_evmcs = nested_enable_evmcs, > > > .get_evmcs_version = nested_get_evmcs_version, > > > + .post_hv_l2_tlb_flush = vmx_post_hv_l2_tlb_flush, > > > }; > > > > I think that the name of the function is misleading, since it is not called > > after each L2 HV tlb flush, but only after a flush which needs to inject > > that synthetic VM exit. > > > > I think something like 'inject_synthetic_l2_hv_tlb_flush_vmexit' > > (not a good name IMHO, but you get the idea) would be better. > > > > Naming is hard indeed, Indeed :-) https://www.monkeyuser.com/2019/_/ > > hv_inject_synthetic_vmexit_post_tlb_flush() Looks great! Best regards, Maxim Levitsky > > seems to be accurate. >