KVM: x86: fix APIC page invalidation

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.

Reported-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Fixes: 38b9917350cb ("kvm: vmx: Implement set_apic_access_page_addr")
Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2")
Cc: <stable@vger.kernel.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Wanpeng Li <wanpeng.li@hotmail.com>
Tested-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 62527e053ee45942fc38ad7fa12abba10e4df998..51679843132829e38ed204eda60d50379a4fabb5 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1448,4 +1448,7 @@ 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 6ca747abfa2f35910f2deceba0738c76a3a613ba..faf843c9b916ead0992d0b155a138c6afdf7ae57 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6764,6 +6764,20 @@ 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 c422c10cd1dd176a973b234f742414cd2443cbff..210bf820385a70967c729259bf762b0d9be98b73 100644 (file)
--- 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);
 }