From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752039AbdLAP1Q (ORCPT ); Fri, 1 Dec 2017 10:27:16 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60890 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbdLAP1P (ORCPT ); Fri, 1 Dec 2017 10:27:15 -0500 Subject: Re: [PATCH 1/2] KVM: x86: fix APIC page invalidation To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , =?UTF-8?Q?Fabian_Gr=c3=bcnbichler?= Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, Andrea Arcangeli , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= References: <20171130161933.GB1606@flask> <20171130180546.4331-1-rkrcmar@redhat.com> From: Paolo Bonzini Message-ID: <47491ef9-5de0-35ac-3358-29966db92541@redhat.com> Date: Fri, 1 Dec 2017 16:27:11 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20171130180546.4331-1-rkrcmar@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Fri, 01 Dec 2017 15:27:14 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/11/2017 19:05, Radim Krčmář wrote: > Implementation of the unpinned APIC page didn't update the VMCS address > cache when invalidation was done through range mmu notifiers. > This became a problem when the page notifier was removed. > > Re-introduce the arch-specific helper and call it from ...range_start. > > Fixes: 38b9917350cb ("kvm: vmx: Implement set_apic_access_page_addr") > Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2") > Signed-off-by: Radim Krčmář > --- > arch/x86/include/asm/kvm_host.h | 3 +++ > arch/x86/kvm/x86.c | 14 ++++++++++++++ > virt/kvm/kvm_main.c | 8 ++++++++ > 3 files changed, 25 insertions(+) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 977de5fb968b..c16c3f924863 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1435,4 +1435,7 @@ static inline int kvm_cpu_get_apicid(int mps_cpu) > #define put_smstate(type, buf, offset, val) \ > *(type *)((buf) + (offset) - 0x7e00) = val > > +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, > + unsigned long start, unsigned long end); > + > #endif /* _ASM_X86_KVM_HOST_H */ > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index eee8e7faf1af..a219974cdb89 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -6778,6 +6778,20 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu) > kvm_x86_ops->tlb_flush(vcpu); > } > > +void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, > + unsigned long start, unsigned long end) > +{ > + unsigned long apic_address; > + > + /* > + * The physical address of apic access page is stored in the VMCS. > + * Update it when it becomes invalid. > + */ > + apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT); > + if (start <= apic_address && apic_address < end) > + kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD); > +} > + > void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu) > { > struct page *page = NULL; > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index c01cff064ec5..b7f4689e373f 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -135,6 +135,11 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm); > static unsigned long long kvm_createvm_count; > static unsigned long long kvm_active_vms; > > +__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, > + unsigned long start, unsigned long end) > +{ > +} > + > bool kvm_is_reserved_pfn(kvm_pfn_t pfn) > { > if (pfn_valid(pfn)) > @@ -360,6 +365,9 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, > kvm_flush_remote_tlbs(kvm); > > spin_unlock(&kvm->mmu_lock); > + > + kvm_arch_mmu_notifier_invalidate_range(kvm, start, end); > + > srcu_read_unlock(&kvm->srcu, idx); > } > > Reviewed-by: Paolo Bonzini