[PATCH 5/5] LoongArch: KVM: Add address alignment check in pch_pic register access

Bibo Mao posted 5 patches 6 months ago
[PATCH 5/5] LoongArch: KVM: Add address alignment check in pch_pic register access
Posted by Bibo Mao 6 months ago
With pch_pic device, its register is based on MMIO address space,
different access size 1/2/4/8 is supported. And base address should
be naturally aligned with its access size, here add alignment check
in its register access emulation function.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
---
 arch/loongarch/kvm/intc/pch_pic.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
index 0710b5ab286e..5ee24dbf3c4c 100644
--- a/arch/loongarch/kvm/intc/pch_pic.c
+++ b/arch/loongarch/kvm/intc/pch_pic.c
@@ -151,6 +151,11 @@ static int kvm_pch_pic_read(struct kvm_vcpu *vcpu,
 		return -EINVAL;
 	}
 
+	if (addr & (len - 1)) {
+		kvm_err("%s: pch pic not aligned addr %llx len %d\n", __func__, addr, len);
+		return -EINVAL;
+	}
+
 	/* statistics of pch pic reading */
 	vcpu->stat.pch_pic_read_exits++;
 	ret = loongarch_pch_pic_read(s, addr, len, val);
@@ -246,6 +251,11 @@ static int kvm_pch_pic_write(struct kvm_vcpu *vcpu,
 		return -EINVAL;
 	}
 
+	if (addr & (len - 1)) {
+		kvm_err("%s: pch pic not aligned addr %llx len %d\n", __func__, addr, len);
+		return -EINVAL;
+	}
+
 	/* statistics of pch pic writing */
 	vcpu->stat.pch_pic_write_exits++;
 	ret = loongarch_pch_pic_write(s, addr, len, val);
-- 
2.39.3
Re: [PATCH 5/5] LoongArch: KVM: Add address alignment check in pch_pic register access
Posted by Huacai Chen 5 months, 3 weeks ago
This one is applied for loongarch-fixes.

Huacai

On Mon, Aug 11, 2025 at 10:15 AM Bibo Mao <maobibo@loongson.cn> wrote:
>
> With pch_pic device, its register is based on MMIO address space,
> different access size 1/2/4/8 is supported. And base address should
> be naturally aligned with its access size, here add alignment check
> in its register access emulation function.
>
> Signed-off-by: Bibo Mao <maobibo@loongson.cn>
> ---
>  arch/loongarch/kvm/intc/pch_pic.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
> index 0710b5ab286e..5ee24dbf3c4c 100644
> --- a/arch/loongarch/kvm/intc/pch_pic.c
> +++ b/arch/loongarch/kvm/intc/pch_pic.c
> @@ -151,6 +151,11 @@ static int kvm_pch_pic_read(struct kvm_vcpu *vcpu,
>                 return -EINVAL;
>         }
>
> +       if (addr & (len - 1)) {
> +               kvm_err("%s: pch pic not aligned addr %llx len %d\n", __func__, addr, len);
> +               return -EINVAL;
> +       }
> +
>         /* statistics of pch pic reading */
>         vcpu->stat.pch_pic_read_exits++;
>         ret = loongarch_pch_pic_read(s, addr, len, val);
> @@ -246,6 +251,11 @@ static int kvm_pch_pic_write(struct kvm_vcpu *vcpu,
>                 return -EINVAL;
>         }
>
> +       if (addr & (len - 1)) {
> +               kvm_err("%s: pch pic not aligned addr %llx len %d\n", __func__, addr, len);
> +               return -EINVAL;
> +       }
> +
>         /* statistics of pch pic writing */
>         vcpu->stat.pch_pic_write_exits++;
>         ret = loongarch_pch_pic_write(s, addr, len, val);
> --
> 2.39.3
>
>