[PATCH] LoongArch: KVM: Return the actual error code in kvm_pch_pic_create()

[PATCH] LoongArch: KVM: Return the actual error code in kvm_pch_pic_create()

[Chaithanya Lagisetty]

kvm_pch_pic_create() sets up the default IRQ routing and reports every
failure as -ENOMEM, discarding the error code it was given:

	ret = kvm_setup_default_irq_routing(kvm);
	if (ret)
		return -ENOMEM;

kvm_setup_default_irq_routing() returns -ENOMEM only when its routing
entry array cannot be allocated. Otherwise it forwards the result of
kvm_set_irq_routing(), which also fails with -EINVAL when an entry is
rejected by setup_routing_entry(). Userspace creating a
KVM_DEV_TYPE_LOONGARCH_PCHPIC device can therefore receive -ENOMEM even
when IRQ routing setup actually failed with -EINVAL.

Return ret so the original error code reaches userspace. This matches
kvm_eiointc_create(), which already propagates the error code from the
helpers it calls.

Only compile-tested.

Fixes: 1928254c5ccb ("LoongArch: KVM: Add irqfd support")
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
---
 arch/loongarch/kvm/intc/pch_pic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
index 2b63b0c2c7ce..7fee60ae01a5 100644
--- a/arch/loongarch/kvm/intc/pch_pic.c
+++ b/arch/loongarch/kvm/intc/pch_pic.c
@@ -444,7 +444,7 @@ static int kvm_pch_pic_create(struct kvm_device *dev, u32 type)
 
 	ret = kvm_setup_default_irq_routing(kvm);
 	if (ret)
-		return -ENOMEM;
+		return ret;
 
 	s = kzalloc_obj(struct loongarch_pch_pic);
 	if (!s)
-- 
2.43.0

Re: [PATCH] LoongArch: KVM: Return the actual error code in kvm_pch_pic_create()

[Bibo Mao]

Hi Chaithanya,

Thanks for patch, there is similar version at:
https://lore.kernel.org/lkml/20260927075240.3007947-6-cui.tao@linux.dev/

Regards
Bibo Mao

在 2026/9/29 13:27, Chaithanya Lagisetty 写道:
> kvm_pch_pic_create() sets up the default IRQ routing and reports every
> failure as -ENOMEM, discarding the error code it was given:
> 
> 	ret = kvm_setup_default_irq_routing(kvm);
> 	if (ret)
> 		return -ENOMEM;
> 
> kvm_setup_default_irq_routing() returns -ENOMEM only when its routing
> entry array cannot be allocated. Otherwise it forwards the result of
> kvm_set_irq_routing(), which also fails with -EINVAL when an entry is
> rejected by setup_routing_entry(). Userspace creating a
> KVM_DEV_TYPE_LOONGARCH_PCHPIC device can therefore receive -ENOMEM even
> when IRQ routing setup actually failed with -EINVAL.
> 
> Return ret so the original error code reaches userspace. This matches
> kvm_eiointc_create(), which already propagates the error code from the
> helpers it calls.
> 
> Only compile-tested.
> 
> Fixes: 1928254c5ccb ("LoongArch: KVM: Add irqfd support")
> Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
> ---
>   arch/loongarch/kvm/intc/pch_pic.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
> index 2b63b0c2c7ce..7fee60ae01a5 100644
> --- a/arch/loongarch/kvm/intc/pch_pic.c
> +++ b/arch/loongarch/kvm/intc/pch_pic.c
> @@ -444,7 +444,7 @@ static int kvm_pch_pic_create(struct kvm_device *dev, u32 type)
>   
>   	ret = kvm_setup_default_irq_routing(kvm);
>   	if (ret)
> -		return -ENOMEM;
> +		return ret;
>   
>   	s = kzalloc_obj(struct loongarch_pch_pic);
>   	if (!s)