[PATCH v2] riscv: vector: Fix context save/restore with xtheadvector

[Yanteng Si]

在 5/23/25 6:25 PM, Han Gao 写道:
> Previously only v0-v7 were correctly saved/restored,
> and the context of v8-v31 are damanged.
> Correctly save/restore v8-v31 to avoid breaking userspace.
> 
> Fixes: d863910eabaf ("riscv: vector: Support xtheadvector save/restore")
> Signed-off-by: Han Gao <rabenda.cn at gmail.com>
> Tested-by: Xiongchuan Tan <tanxiongchuan at isrc.iscas.ac.cn>
> Reviewed-by: Charlie Jenkins <charlie at rivosinc.com>
Reviewed-by: Yanteng Si <si.yanteng at linux.dev>

Thanks,
Yanteng
> ---
> 
> Changes in v2:
>    Add fix tag
>    Improve commit mesage
> 
> v1: https://lore.kernel.org/linux-riscv/c221c98dc2369ea691e3eb664bf084dc909496f6.1747934680.git.rabenda.cn@gmail.com/
> 
>   arch/riscv/include/asm/vector.h | 12 ++++++------
>   1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h
> index e8a83f55be2b..7df6355023a3 100644
> --- a/arch/riscv/include/asm/vector.h
> +++ b/arch/riscv/include/asm/vector.h
> @@ -200,11 +200,11 @@ static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
>   			THEAD_VSETVLI_T4X0E8M8D1
>   			THEAD_VSB_V_V0T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VSB_V_V0T0
> +			THEAD_VSB_V_V8T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VSB_V_V0T0
> +			THEAD_VSB_V_V16T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VSB_V_V0T0
> +			THEAD_VSB_V_V24T0
>   			: : "r" (datap) : "memory", "t0", "t4");
>   	} else {
>   		asm volatile (
> @@ -236,11 +236,11 @@ static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_
>   			THEAD_VSETVLI_T4X0E8M8D1
>   			THEAD_VLB_V_V0T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VLB_V_V0T0
> +			THEAD_VLB_V_V8T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VLB_V_V0T0
> +			THEAD_VLB_V_V16T0
>   			"add		t0, t0, t4\n\t"
> -			THEAD_VLB_V_V0T0
> +			THEAD_VLB_V_V24T0
>   			: : "r" (datap) : "memory", "t0", "t4");
>   	} else {
>   		asm volatile (