Re: [PATCH 7/7] KVM: Drop kvm_arch_sync_events() now that all implementations are nops

[bibo mao <maobibo@xxxxxxxxxxx>]

Reviewed-by: Bibo Mao <maobibo@xxxxxxxxxxx>

On 2025/2/25 上午7:55, Sean Christopherson wrote:
> Remove kvm_arch_sync_events() now that x86 no longer uses it (no other
> arch has ever used it).
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> ---
>   arch/arm64/include/asm/kvm_host.h     | 2 --
>   arch/loongarch/include/asm/kvm_host.h | 1 -
>   arch/mips/include/asm/kvm_host.h      | 1 -
>   arch/powerpc/include/asm/kvm_host.h   | 1 -
>   arch/riscv/include/asm/kvm_host.h     | 2 --
>   arch/s390/include/asm/kvm_host.h      | 1 -
>   arch/x86/kvm/x86.c                    | 5 -----
>   include/linux/kvm_host.h              | 1 -
>   virt/kvm/kvm_main.c                   | 1 -
>   9 files changed, 15 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index 7cfa024de4e3..40897bd2b4a3 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -1346,8 +1346,6 @@ static inline bool kvm_system_needs_idmapped_vectors(void)
>   	return cpus_have_final_cap(ARM64_SPECTRE_V3A);
>   }
>   
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
> -
>   void kvm_init_host_debug_data(void);
>   void kvm_vcpu_load_debug(struct kvm_vcpu *vcpu);
>   void kvm_vcpu_put_debug(struct kvm_vcpu *vcpu);
> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
> index 590982cd986e..ab5b7001e2ff 100644
> --- a/arch/loongarch/include/asm/kvm_host.h
> +++ b/arch/loongarch/include/asm/kvm_host.h
> @@ -320,7 +320,6 @@ static inline bool kvm_is_ifetch_fault(struct kvm_vcpu_arch *arch)
>   
>   /* Misc */
>   static inline void kvm_arch_hardware_unsetup(void) {}
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>   static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
>   static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
>   static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
> diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
> index f7222eb594ea..c14b10821817 100644
> --- a/arch/mips/include/asm/kvm_host.h
> +++ b/arch/mips/include/asm/kvm_host.h
> @@ -886,7 +886,6 @@ extern unsigned long kvm_mips_get_ramsize(struct kvm *kvm);
>   extern int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
>   			     struct kvm_mips_interrupt *irq);
>   
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>   static inline void kvm_arch_free_memslot(struct kvm *kvm,
>   					 struct kvm_memory_slot *slot) {}
>   static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
> diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
> index 6e1108f8fce6..2d139c807577 100644
> --- a/arch/powerpc/include/asm/kvm_host.h
> +++ b/arch/powerpc/include/asm/kvm_host.h
> @@ -902,7 +902,6 @@ struct kvm_vcpu_arch {
>   #define __KVM_HAVE_ARCH_WQP
>   #define __KVM_HAVE_CREATE_DEVICE
>   
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>   static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
>   static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {}
>   static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
> diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
> index cc33e35cd628..0e9c2fab6378 100644
> --- a/arch/riscv/include/asm/kvm_host.h
> +++ b/arch/riscv/include/asm/kvm_host.h
> @@ -301,8 +301,6 @@ static inline bool kvm_arch_pmi_in_guest(struct kvm_vcpu *vcpu)
>   	return IS_ENABLED(CONFIG_GUEST_PERF_EVENTS) && !!vcpu;
>   }
>   
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
> -
>   #define KVM_RISCV_GSTAGE_TLB_MIN_ORDER		12
>   
>   void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid,
> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
> index 9a367866cab0..424f899d8163 100644
> --- a/arch/s390/include/asm/kvm_host.h
> +++ b/arch/s390/include/asm/kvm_host.h
> @@ -1056,7 +1056,6 @@ bool kvm_s390_pv_cpu_is_protected(struct kvm_vcpu *vcpu);
>   extern int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc);
>   extern int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc);
>   
> -static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>   static inline void kvm_arch_free_memslot(struct kvm *kvm,
>   					 struct kvm_memory_slot *slot) {}
>   static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index ea445e6579f1..454fd6b8f3db 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -12770,11 +12770,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
>   	return ret;
>   }
>   
> -void kvm_arch_sync_events(struct kvm *kvm)
> -{
> -
> -}
> -
>   /**
>    * __x86_set_memory_region: Setup KVM internal memory slot
>    *
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index c28a6aa1f2ed..5438a1b446a6 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1747,7 +1747,6 @@ static inline void kvm_unregister_perf_callbacks(void) {}
>   
>   int kvm_arch_init_vm(struct kvm *kvm, unsigned long type);
>   void kvm_arch_destroy_vm(struct kvm *kvm);
> -void kvm_arch_sync_events(struct kvm *kvm);
>   
>   int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
>   
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 991e8111e88b..55153494ac70 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1271,7 +1271,6 @@ static void kvm_destroy_vm(struct kvm *kvm)
>   	kvm_destroy_pm_notifier(kvm);
>   	kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
>   	kvm_destroy_vm_debugfs(kvm);
> -	kvm_arch_sync_events(kvm);
>   	mutex_lock(&kvm_lock);
>   	list_del(&kvm->vm_list);
>   	mutex_unlock(&kvm_lock);