Re: [PATCH] scs: Fix a wrong parameter in __scs_magic

[Will Deacon]

On Mon, Jul 04, 2022 at 03:04:03PM +0800, Wan Jiabing wrote:
> __scs_magic() needs a 'void *' variable, but a 'struct task_struct *'
> is given. 'task_scs(tsk)' is the starting address of the task's shadow
> call stack, and '__scs_magic(task_scs(tsk))' is the end address of the
> task's shadow call stack.
> Here should be '__scs_magic(task_scs(tsk))'.
> 
> Fixes: 5bbaf9d1fcb9 ("scs: Add support for stack usage debugging")
> Signed-off-by: Xie Jiyuan <xiejiyuan@xxxxxxxx>
> Signed-off-by: Wan Jiabing <wanjiabing@xxxxxxxx>
> ---
>  kernel/scs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/scs.c b/kernel/scs.c
> index b7e1b096d906..4c1ce6a6172d 100644
> --- a/kernel/scs.c
> +++ b/kernel/scs.c
> @@ -125,7 +125,7 @@ static void scs_check_usage(struct task_struct *tsk)
>  	if (!IS_ENABLED(CONFIG_DEBUG_STACK_USAGE))
>  		return;
>  
> -	for (p = task_scs(tsk); p < __scs_magic(tsk); ++p) {
> +	for (p = task_scs(tsk); p < __scs_magic(task_scs(tsk)); ++p) {
>  		if (!READ_ONCE_NOCHECK(*p))
>  			break;
>  		used += sizeof(*p);

Acked-by: Will Deacon <will@xxxxxxxxxx>

I'm assuming this will go via Andrew or Kees.

Will