2019-11-28 03:13:02

by Miaohe Lin

Subject: [PATCH] KVM: arm64: eliminate unnecessary var err and jump label in set_core_reg()

From: Miaohe Lin <[email protected]>

The var err and jump label out isn't really needed in
set_core_reg(). Clean them up.
Signed-off-by: Miaohe Lin <[email protected]>
---
arch/arm64/kvm/guest.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 3b836c91609e..88eb6e5399ed 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -159,7 +159,6 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
__uint128_t tmp;
void *valp = &tmp;
u64 off;
- int err = 0;

/* Our ID is an index into the kvm_regs struct. */
off = core_reg_offset_from_id(reg->id);
@@ -173,10 +172,8 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
return -EINVAL;

- if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
- err = -EFAULT;
- goto out;
- }
+ if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;

if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK;
@@ -200,14 +197,12 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return -EINVAL;
break;
default:
- err = -EINVAL;
- goto out;
+ return -EINVAL;
}
}

memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
-out:
- return err;
+ return 0;
}

#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
--
2.19.1

2019-11-28 09:56:15

by Eric Auger

Subject: Re: [PATCH] KVM: arm64: eliminate unnecessary var err and jump label in set_core_reg()

Hi,

On 11/28/19 4:09 AM, linmiaohe wrote:
> From: Miaohe Lin <[email protected]>
>
> The var err and jump label out isn't really needed in
> set_core_reg(). Clean them up.
> Signed-off-by: Miaohe Lin <[email protected]>
Reviewed-by: Eric Auger <[email protected]>

Thanks

Eric

> ---
> arch/arm64/kvm/guest.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
> index 3b836c91609e..88eb6e5399ed 100644
> --- a/arch/arm64/kvm/guest.c
> +++ b/arch/arm64/kvm/guest.c
> @@ -159,7 +159,6 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
> __uint128_t tmp;
> void *valp = &tmp;
> u64 off;
> - int err = 0;
>
> /* Our ID is an index into the kvm_regs struct. */
> off = core_reg_offset_from_id(reg->id);
> @@ -173,10 +172,8 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
> if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
> return -EINVAL;
>
> - if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
> - err = -EFAULT;
> - goto out;
> - }
> + if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id)))
> + return -EFAULT;
>
> if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
> u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK;
> @@ -200,14 +197,12 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
> return -EINVAL;
> break;
> default:
> - err = -EINVAL;
> - goto out;
> + return -EINVAL;
> }
> }
>
> memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
> -out:
> - return err;
> + return 0;
> }
>
> #define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
>