On Fri, 31 May 2019, Petr Mladek wrote:
> The err_buf array uses 128 bytes of stack space. Move it off the stack
> by making it static. It's safe to use a shared buffer because
> klp_try_switch_task() is called under klp_mutex.
>
> Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
> Acked-by: Miroslav Benes <mbenes@xxxxxxx>
> Reviewed-by: Kamalesh Babulal <kamalesh@xxxxxxxxxxxxxxxxxx>
> ---
> kernel/livepatch/transition.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
> index 1bf362df76e1..5c4f0c1f826e 100644
> --- a/kernel/livepatch/transition.c
> +++ b/kernel/livepatch/transition.c
> @@ -280,11 +280,11 @@ static int klp_check_stack(struct task_struct *task, char *err_buf)
> */
> static bool klp_try_switch_task(struct task_struct *task)
> {
> + static char err_buf[STACK_ERR_BUF_SIZE];
> struct rq *rq;
> struct rq_flags flags;
> int ret;
> bool success = false;
> - char err_buf[STACK_ERR_BUF_SIZE];
>
> err_buf[0] = '\0';
>
> @@ -327,7 +327,6 @@ static bool klp_try_switch_task(struct task_struct *task)
> pr_debug("%s", err_buf);
>
> return success;
> -
> }
This could go in separately as it is not connected to the rest of the
series.
Miroslav
