Re: [PATCH][next] kdb: remove redundant check for scancode 0xe0

From: Doug Anderson
Date: Tue Jun 10 2025 - 19:38:27 EST


Hi,

On Wed, May 7, 2025 at 3:44 AM Colin Ian King <colin.i.king@xxxxxxxxx> wrote:
>
> The check for scancode 0xe0 is always false because earlier on
> the scan code is masked with 0x7f so there are never going to
> be values greater than 0x7f. Remove the redundant check.
>
> Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx>
> ---
> kernel/debug/kdb/kdb_keyboard.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c
> index 3a74604fdb8a..386d30e530b7 100644
> --- a/kernel/debug/kdb/kdb_keyboard.c
> +++ b/kernel/debug/kdb/kdb_keyboard.c
> @@ -145,9 +145,6 @@ int kdb_get_kbd_char(void)
> return CTRL('F');
> }
>
> - if (scancode == 0xe0)
> - return -1;
> -

What a glorious bit of undocumented code. I agree that this is dead
code and should be safe to remove.

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>