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

[Sami Tolvanen]

On Sat, Oct 11, 2025 at 1:23 AM Zhichi Lin <zhichi.lin@xxxxxxxx> 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: Jiyuan Xie <xiejiyuan@xxxxxxxx>
> Signed-off-by: Zhichi Lin <zhichi.lin@xxxxxxxx>
> ---
>  kernel/scs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/scs.c b/kernel/scs.c
> index d7809affe..772488afd 100644
> --- a/kernel/scs.c
> +++ b/kernel/scs.c
> @@ -135,7 +135,7 @@ 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);

Looks correct to me. Thanks for the fix!

Reviewed-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Sami