[PATCH v2] KVM: x86: Unconditionally call x86 ops that are always implemented

[PATCH v2] KVM: x86: Unconditionally call x86 ops that are always implemented

[Sean Christopherson]

Remove a few stale checks for non-NULL ops now that the ops in question
are implemented by both VMX and SVM.

Note, this is **not** stable material, the Fixes tags are there purely
to show when a particular op was first supported by both VMX and SVM.

Fixes: 74f169090b6f ("kvm/svm: Setup MCG_CAP on AMD properly")
Fixes: b31c114b82b2 ("KVM: X86: Provide a capability to disable PAUSE intercepts")
Fixes: 411b44ba80ab ("svm: Implements update_pi_irte hook to setup posted interrupt")
Cc: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---

v2: Give update_pi_iret the same treatment [Krish].

 arch/x86/kvm/x86.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 01e18caac825..e7c993f0cbed 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3506,8 +3506,7 @@ static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu,
 	for (bank = 0; bank < bank_num; bank++)
 		vcpu->arch.mce_banks[bank*4] = ~(u64)0;
 
-	if (kvm_x86_ops->setup_mce)
-		kvm_x86_ops->setup_mce(vcpu);
+	kvm_x86_ops->setup_mce(vcpu);
 out:
 	return r;
 }
@@ -9313,10 +9312,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	kvm_page_track_init(kvm);
 	kvm_mmu_init_vm(kvm);
 
-	if (kvm_x86_ops->vm_init)
-		return kvm_x86_ops->vm_init(kvm);
-
-	return 0;
+	return kvm_x86_ops->vm_init(kvm);
 }
 
 static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
@@ -9992,7 +9988,7 @@ EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
 
 bool kvm_arch_has_irq_bypass(void)
 {
-	return kvm_x86_ops->update_pi_irte != NULL;
+	return true;
 }
 
 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
@@ -10032,9 +10028,6 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
 int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq,
 				   uint32_t guest_irq, bool set)
 {
-	if (!kvm_x86_ops->update_pi_irte)
-		return -EINVAL;
-
 	return kvm_x86_ops->update_pi_irte(kvm, host_irq, guest_irq, set);
 }
 
-- 
2.22.0

Re: [PATCH v2] KVM: x86: Unconditionally call x86 ops that are always implemented

[Krish Sadhukhan]

On 08/02/2019 03:06 PM, Sean Christopherson wrote:
> Remove a few stale checks for non-NULL ops now that the ops in question
> are implemented by both VMX and SVM.
>
> Note, this is **not** stable material, the Fixes tags are there purely
> to show when a particular op was first supported by both VMX and SVM.
>
> Fixes: 74f169090b6f ("kvm/svm: Setup MCG_CAP on AMD properly")
> Fixes: b31c114b82b2 ("KVM: X86: Provide a capability to disable PAUSE intercepts")
> Fixes: 411b44ba80ab ("svm: Implements update_pi_irte hook to setup posted interrupt")
> Cc: Krish Sadhukhan <krish.sadhukhan@oracle.com>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
>
> v2: Give update_pi_iret the same treatment [Krish].
>
>   arch/x86/kvm/x86.c | 13 +++----------
>   1 file changed, 3 insertions(+), 10 deletions(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 01e18caac825..e7c993f0cbed 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -3506,8 +3506,7 @@ static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu,
>   	for (bank = 0; bank < bank_num; bank++)
>   		vcpu->arch.mce_banks[bank*4] = ~(u64)0;
>   
> -	if (kvm_x86_ops->setup_mce)
> -		kvm_x86_ops->setup_mce(vcpu);
> +	kvm_x86_ops->setup_mce(vcpu);
>   out:
>   	return r;
>   }
> @@ -9313,10 +9312,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
>   	kvm_page_track_init(kvm);
>   	kvm_mmu_init_vm(kvm);
>   
> -	if (kvm_x86_ops->vm_init)
> -		return kvm_x86_ops->vm_init(kvm);
> -
> -	return 0;
> +	return kvm_x86_ops->vm_init(kvm);
>   }
>   
>   static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
> @@ -9992,7 +9988,7 @@ EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
>   
>   bool kvm_arch_has_irq_bypass(void)

Now that this is returning true always and that this is called only in 
kvm_irqfd_assign(), this can perhaps be removed altogether ?

>   {
> -	return kvm_x86_ops->update_pi_irte != NULL;
> +	return true;
>   }
>   
>   int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
> @@ -10032,9 +10028,6 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
>   int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq,
>   				   uint32_t guest_irq, bool set)
>   {
> -	if (!kvm_x86_ops->update_pi_irte)
> -		return -EINVAL;
> -
>   	return kvm_x86_ops->update_pi_irte(kvm, host_irq, guest_irq, set);
>   }
>   

Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>

Re: [PATCH v2] KVM: x86: Unconditionally call x86 ops that are always implemented

[Sean Christopherson]

On Fri, Aug 02, 2019 at 03:48:27PM -0700, Krish Sadhukhan wrote:
> 
> On 08/02/2019 03:06 PM, Sean Christopherson wrote:
> >Remove a few stale checks for non-NULL ops now that the ops in question
> >are implemented by both VMX and SVM.
> >
> >Note, this is **not** stable material, the Fixes tags are there purely
> >to show when a particular op was first supported by both VMX and SVM.
> >
> >Fixes: 74f169090b6f ("kvm/svm: Setup MCG_CAP on AMD properly")
> >Fixes: b31c114b82b2 ("KVM: X86: Provide a capability to disable PAUSE intercepts")
> >Fixes: 411b44ba80ab ("svm: Implements update_pi_irte hook to setup posted interrupt")
> >Cc: Krish Sadhukhan <krish.sadhukhan@oracle.com>
> >Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> >---
> >
> >v2: Give update_pi_iret the same treatment [Krish].
> >
> >  arch/x86/kvm/x86.c | 13 +++----------
> >  1 file changed, 3 insertions(+), 10 deletions(-)
> >
> >diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> >index 01e18caac825..e7c993f0cbed 100644
> >--- a/arch/x86/kvm/x86.c
> >+++ b/arch/x86/kvm/x86.c
> >@@ -3506,8 +3506,7 @@ static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu,
> >  	for (bank = 0; bank < bank_num; bank++)
> >  		vcpu->arch.mce_banks[bank*4] = ~(u64)0;
> >-	if (kvm_x86_ops->setup_mce)
> >-		kvm_x86_ops->setup_mce(vcpu);
> >+	kvm_x86_ops->setup_mce(vcpu);
> >  out:
> >  	return r;
> >  }
> >@@ -9313,10 +9312,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> >  	kvm_page_track_init(kvm);
> >  	kvm_mmu_init_vm(kvm);
> >-	if (kvm_x86_ops->vm_init)
> >-		return kvm_x86_ops->vm_init(kvm);
> >-
> >-	return 0;
> >+	return kvm_x86_ops->vm_init(kvm);
> >  }
> >  static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
> >@@ -9992,7 +9988,7 @@ EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
> >  bool kvm_arch_has_irq_bypass(void)
> 
> Now that this is returning true always and that this is called only in
> kvm_irqfd_assign(), this can perhaps be removed altogether ?

No go, PowerPC has a conditional implementation.