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 19776CCA47D for ; Wed, 22 Jun 2022 09:22:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354229AbiFVJWv (ORCPT ); Wed, 22 Jun 2022 05:22:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233679AbiFVJWs (ORCPT ); Wed, 22 Jun 2022 05:22:48 -0400 Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 724A535261; Wed, 22 Jun 2022 02:22:47 -0700 (PDT) Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1o3wZ9-0000gW-BV; Wed, 22 Jun 2022 09:22:27 +0000 Received: from 54-240-197-231.amazon.com ([54.240.197.231] helo=debian.cbg12.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1o3wZ8-0002BS-VW; Wed, 22 Jun 2022 09:22:27 +0000 From: Paul Durrant To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Paul Durrant , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" Subject: [PATCH] KVM: x86/xen: Update Xen CPUID Leaf 4 (tsc info) sub-leaves, if present Date: Wed, 22 Jun 2022 10:22:02 +0100 Message-Id: <20220622092202.15548-1-pdurrant@amazon.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The scaling information in sub-leaf 1 should match the values in the 'vcpu_info' sub-structure 'time_info' (a.k.a. pvclock_vcpu_time_info) which is shared with the guest. The offset values are not set since a TSC offset is already applied. The host TSC frequency should also be set in sub-leaf 2. This patch adds a new kvm_xen_set_cpuid() function that scans for the relevant CPUID leaf when the CPUID information is updated by the VMM and stashes pointers to the sub-leaves in the kvm_vcpu_xen structure. The values are then updated by a call to the, also new, kvm_xen_setup_tsc_info() function made at the end of kvm_guest_time_update() just before entering the guest. Signed-off-by: Paul Durrant --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/cpuid.c | 2 ++ arch/x86/kvm/x86.c | 1 + arch/x86/kvm/xen.c | 41 +++++++++++++++++++++++++++++++++ arch/x86/kvm/xen.h | 10 ++++++++ 5 files changed, 56 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 1038ccb7056a..f77a4940542f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -638,6 +638,8 @@ struct kvm_vcpu_xen { struct hrtimer timer; int poll_evtchn; struct timer_list poll_timer; + struct kvm_cpuid_entry2 *tsc_info_1; + struct kvm_cpuid_entry2 *tsc_info_2; }; struct kvm_vcpu_arch { diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index d47222ab8e6e..eb6cd88c974a 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -25,6 +25,7 @@ #include "mmu.h" #include "trace.h" #include "pmu.h" +#include "xen.h" /* * Unlike "struct cpuinfo_x86.x86_capability", kvm_cpu_caps doesn't need to be @@ -310,6 +311,7 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) __cr4_reserved_bits(guest_cpuid_has, vcpu); kvm_hv_set_cpuid(vcpu); + kvm_xen_set_cpuid(vcpu); /* Invoke the vendor callback only after the above state is updated. */ static_call(kvm_x86_vcpu_after_set_cpuid)(vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 00e23dc518e0..8b45f9975e45 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3123,6 +3123,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) if (vcpu->xen.vcpu_time_info_cache.active) kvm_setup_guest_pvclock(v, &vcpu->xen.vcpu_time_info_cache, 0); kvm_hv_setup_tsc_page(v->kvm, &vcpu->hv_clock); + kvm_xen_setup_tsc_info(v); return 0; } diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index 610beba35907..a016ff85264d 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -10,6 +10,9 @@ #include "xen.h" #include "hyperv.h" #include "lapic.h" +#include "cpuid.h" + +#include #include #include @@ -1855,3 +1858,41 @@ void kvm_xen_destroy_vm(struct kvm *kvm) if (kvm->arch.xen_hvm_config.msr) static_branch_slow_dec_deferred(&kvm_xen_enabled); } + +void kvm_xen_set_cpuid(struct kvm_vcpu *vcpu) +{ + u32 base = 0; + u32 function; + + for_each_possible_hypervisor_cpuid_base(function) { + struct kvm_cpuid_entry2 *entry = kvm_find_cpuid_entry(vcpu, function, 0); + + if (entry && + entry->ebx == XEN_CPUID_SIGNATURE_EBX && + entry->ecx == XEN_CPUID_SIGNATURE_ECX && + entry->edx == XEN_CPUID_SIGNATURE_EDX) { + base = function; + break; + } + } + if (!base) + return; + + function = base | XEN_CPUID_LEAF(3); + vcpu->arch.xen.tsc_info_1 = kvm_find_cpuid_entry(vcpu, function, 1); + vcpu->arch.xen.tsc_info_2 = kvm_find_cpuid_entry(vcpu, function, 2); +} + +void kvm_xen_setup_tsc_info(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *entry = vcpu->arch.xen.tsc_info_1; + + if (entry) { + entry->ecx = vcpu->arch.hv_clock.tsc_to_system_mul; + entry->edx = vcpu->arch.hv_clock.tsc_shift; + } + + entry = vcpu->arch.xen.tsc_info_2; + if (entry) + entry->eax = vcpu->arch.hw_tsc_khz; +} diff --git a/arch/x86/kvm/xen.h b/arch/x86/kvm/xen.h index 532a535a9e99..1afb663318a9 100644 --- a/arch/x86/kvm/xen.h +++ b/arch/x86/kvm/xen.h @@ -32,6 +32,8 @@ int kvm_xen_set_evtchn_fast(struct kvm_xen_evtchn *xe, int kvm_xen_setup_evtchn(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e, const struct kvm_irq_routing_entry *ue); +void kvm_xen_set_cpuid(struct kvm_vcpu *vcpu); +void kvm_xen_setup_tsc_info(struct kvm_vcpu *vcpu); static inline bool kvm_xen_msr_enabled(struct kvm *kvm) { @@ -135,6 +137,14 @@ static inline bool kvm_xen_timer_enabled(struct kvm_vcpu *vcpu) { return false; } + +static inline void kvm_xen_set_cpuid(struct kvm_vcpu *vcpu) +{ +} + +static inline void kvm_xen_setup_tsc_info(struct kvm_vcpu *vcpu) +{ +} #endif int kvm_xen_hypercall(struct kvm_vcpu *vcpu); -- 2.20.1