diff mbox series

[RESEND] KVM: X86: eliminate obsolete KVM_GET_CPUID2 ioctl

Message ID 1582516032-5161-1-git-send-email-linmiaohe@huawei.com (mailing list archive)
State New, archived
Headers show
Series [RESEND] KVM: X86: eliminate obsolete KVM_GET_CPUID2 ioctl | expand

Commit Message

Miaohe Lin Feb. 24, 2020, 3:47 a.m. UTC 
From: Miaohe Lin <linmiaohe@huawei.com>

KVM_GET_CPUID2 ioctl is straight up broken and not used anywhere. Remove
it directly.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 arch/x86/kvm/cpuid.c           | 20 --------------------
 arch/x86/kvm/cpuid.h           |  3 ---
 arch/x86/kvm/x86.c             | 17 -----------------
 include/uapi/linux/kvm.h       |  1 -
 tools/include/uapi/linux/kvm.h |  1 -
 5 files changed, 42 deletions(-)

Comments

Vitaly Kuznetsov Feb. 24, 2020, 10:06 a.m. UTC | #1 
linmiaohe <linmiaohe@huawei.com> writes:

> From: Miaohe Lin <linmiaohe@huawei.com>
>
> KVM_GET_CPUID2 ioctl is straight up broken 

It may make sense to add the gory details from your previous patch where
you were trying to fix it.

> and not used anywhere. Remove it directly.
>
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  arch/x86/kvm/cpuid.c           | 20 --------------------
>  arch/x86/kvm/cpuid.h           |  3 ---
>  arch/x86/kvm/x86.c             | 17 -----------------
>  include/uapi/linux/kvm.h       |  1 -
>  tools/include/uapi/linux/kvm.h |  1 -
>  5 files changed, 42 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index b1c469446b07..5e041a1282b8 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -261,26 +261,6 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
>  	return r;
>  }
>  
> -int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
> -			      struct kvm_cpuid2 *cpuid,
> -			      struct kvm_cpuid_entry2 __user *entries)
> -{
> -	int r;
> -
> -	r = -E2BIG;
> -	if (cpuid->nent < vcpu->arch.cpuid_nent)
> -		goto out;
> -	r = -EFAULT;
> -	if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
> -			 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
> -		goto out;
> -	return 0;
> -
> -out:
> -	cpuid->nent = vcpu->arch.cpuid_nent;
> -	return r;
> -}
> -
>  static __always_inline void cpuid_mask(u32 *word, int wordnum)
>  {
>  	reverse_cpuid_check(wordnum);
> diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
> index 7366c618aa04..76555de38e1b 100644
> --- a/arch/x86/kvm/cpuid.h
> +++ b/arch/x86/kvm/cpuid.h
> @@ -19,9 +19,6 @@ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
>  int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
>  			      struct kvm_cpuid2 *cpuid,
>  			      struct kvm_cpuid_entry2 __user *entries);
> -int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
> -			      struct kvm_cpuid2 *cpuid,
> -			      struct kvm_cpuid_entry2 __user *entries);
>  bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
>  	       u32 *ecx, u32 *edx, bool check_limit);
>  
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index fbabb2f06273..ddcc51b89e2c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4286,23 +4286,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
>  					      cpuid_arg->entries);
>  		break;
>  	}
> -	case KVM_GET_CPUID2: {
> -		struct kvm_cpuid2 __user *cpuid_arg = argp;
> -		struct kvm_cpuid2 cpuid;
> -
> -		r = -EFAULT;
> -		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
> -			goto out;
> -		r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid,
> -					      cpuid_arg->entries);
> -		if (r)
> -			goto out;
> -		r = -EFAULT;
> -		if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
> -			goto out;
> -		r = 0;
> -		break;
> -	}
>  	case KVM_GET_MSRS: {
>  		int idx = srcu_read_lock(&vcpu->kvm->srcu);
>  		r = msr_io(vcpu, argp, do_get_msr, 1);
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 4b95f9a31a2f..b37b8c1f300e 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1380,7 +1380,6 @@ struct kvm_s390_ucas_mapping {
>  #define KVM_GET_LAPIC             _IOR(KVMIO,  0x8e, struct kvm_lapic_state)
>  #define KVM_SET_LAPIC             _IOW(KVMIO,  0x8f, struct kvm_lapic_state)
>  #define KVM_SET_CPUID2            _IOW(KVMIO,  0x90, struct kvm_cpuid2)
> -#define KVM_GET_CPUID2            _IOWR(KVMIO, 0x91, struct kvm_cpuid2)

Even if we decide to be strong and remove KVM_GET_CPUID2 completely, I'd
suggest we leave a comment here saying that it was deprecated. Leaving
the branch in case (returning the same -EINVAL as passing an unsupported
IOCTL) may also make sense (with a 'deprecated' comment of course).

>  /* Available with KVM_CAP_VAPIC */
>  #define KVM_TPR_ACCESS_REPORTING  _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
>  /* Available with KVM_CAP_VAPIC */
> diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
> index f0a16b4adbbd..431106dedd2c 100644
> --- a/tools/include/uapi/linux/kvm.h
> +++ b/tools/include/uapi/linux/kvm.h
> @@ -1379,7 +1379,6 @@ struct kvm_s390_ucas_mapping {
>  #define KVM_GET_LAPIC             _IOR(KVMIO,  0x8e, struct kvm_lapic_state)
>  #define KVM_SET_LAPIC             _IOW(KVMIO,  0x8f, struct kvm_lapic_state)
>  #define KVM_SET_CPUID2            _IOW(KVMIO,  0x90, struct kvm_cpuid2)
> -#define KVM_GET_CPUID2            _IOWR(KVMIO, 0x91, struct kvm_cpuid2)
>  /* Available with KVM_CAP_VAPIC */
>  #define KVM_TPR_ACCESS_REPORTING  _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
>  /* Available with KVM_CAP_VAPIC */
diff mbox series

Patch

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b1c469446b07..5e041a1282b8 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -261,26 +261,6 @@  int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
 	return r;
 }
 
-int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
-			      struct kvm_cpuid2 *cpuid,
-			      struct kvm_cpuid_entry2 __user *entries)
-{
-	int r;
-
-	r = -E2BIG;
-	if (cpuid->nent < vcpu->arch.cpuid_nent)
-		goto out;
-	r = -EFAULT;
-	if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
-			 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
-		goto out;
-	return 0;
-
-out:
-	cpuid->nent = vcpu->arch.cpuid_nent;
-	return r;
-}
-
 static __always_inline void cpuid_mask(u32 *word, int wordnum)
 {
 	reverse_cpuid_check(wordnum);
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 7366c618aa04..76555de38e1b 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -19,9 +19,6 @@  int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
 			      struct kvm_cpuid2 *cpuid,
 			      struct kvm_cpuid_entry2 __user *entries);
-int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
-			      struct kvm_cpuid2 *cpuid,
-			      struct kvm_cpuid_entry2 __user *entries);
 bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
 	       u32 *ecx, u32 *edx, bool check_limit);
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fbabb2f06273..ddcc51b89e2c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4286,23 +4286,6 @@  long kvm_arch_vcpu_ioctl(struct file *filp,
 					      cpuid_arg->entries);
 		break;
 	}
-	case KVM_GET_CPUID2: {
-		struct kvm_cpuid2 __user *cpuid_arg = argp;
-		struct kvm_cpuid2 cpuid;
-
-		r = -EFAULT;
-		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
-			goto out;
-		r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid,
-					      cpuid_arg->entries);
-		if (r)
-			goto out;
-		r = -EFAULT;
-		if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
-			goto out;
-		r = 0;
-		break;
-	}
 	case KVM_GET_MSRS: {
 		int idx = srcu_read_lock(&vcpu->kvm->srcu);
 		r = msr_io(vcpu, argp, do_get_msr, 1);
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 4b95f9a31a2f..b37b8c1f300e 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1380,7 +1380,6 @@  struct kvm_s390_ucas_mapping {
 #define KVM_GET_LAPIC             _IOR(KVMIO,  0x8e, struct kvm_lapic_state)
 #define KVM_SET_LAPIC             _IOW(KVMIO,  0x8f, struct kvm_lapic_state)
 #define KVM_SET_CPUID2            _IOW(KVMIO,  0x90, struct kvm_cpuid2)
-#define KVM_GET_CPUID2            _IOWR(KVMIO, 0x91, struct kvm_cpuid2)
 /* Available with KVM_CAP_VAPIC */
 #define KVM_TPR_ACCESS_REPORTING  _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
 /* Available with KVM_CAP_VAPIC */
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index f0a16b4adbbd..431106dedd2c 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -1379,7 +1379,6 @@  struct kvm_s390_ucas_mapping {
 #define KVM_GET_LAPIC             _IOR(KVMIO,  0x8e, struct kvm_lapic_state)
 #define KVM_SET_LAPIC             _IOW(KVMIO,  0x8f, struct kvm_lapic_state)
 #define KVM_SET_CPUID2            _IOW(KVMIO,  0x90, struct kvm_cpuid2)
-#define KVM_GET_CPUID2            _IOWR(KVMIO, 0x91, struct kvm_cpuid2)
 /* Available with KVM_CAP_VAPIC */
 #define KVM_TPR_ACCESS_REPORTING  _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
 /* Available with KVM_CAP_VAPIC */