[PATCH v2 03/11] tty: kbd: reduce stack size with KASAN
From: Arnd Bergmann <arnd@arndb.de>
Date: 2017-06-14 21:19:31
Also in:
lkml
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
As reported by kernelci, some functions in the VT code use significant amounts of kernel stack when local variables get inlined into the caller multiple times: drivers/tty/vt/keyboard.c: In function 'kbd_keycode': drivers/tty/vt/keyboard.c:1452:1: error: the frame size of 2240 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] Annotating those functions as noinline_if_stackbloat prevents the inlining and reduces the overall stack usage in this driver. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/tty/vt/keyboard.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index f4166263bb3a..c0d111444a0e 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c@@ -301,13 +301,13 @@ int kbd_rate(struct kbd_repeat *rpt) /* * Helper Functions. */ -static void put_queue(struct vc_data *vc, int ch) +static noinline_if_stackbloat void put_queue(struct vc_data *vc, int ch) { tty_insert_flip_char(&vc->port, ch, 0); tty_schedule_flip(&vc->port); } -static void puts_queue(struct vc_data *vc, char *cp) +static noinline_if_stackbloat void puts_queue(struct vc_data *vc, char *cp) { while (*cp) { tty_insert_flip_char(&vc->port, *cp, 0);
@@ -555,7 +555,7 @@ static void fn_inc_console(struct vc_data *vc) set_console(i); } -static void fn_send_intr(struct vc_data *vc) +static noinline_if_stackbloat void fn_send_intr(struct vc_data *vc) { tty_insert_flip_char(&vc->port, 0, TTY_BREAK); tty_schedule_flip(&vc->port);
--
2.9.0