[PATCH] Input: keyboard - add locking around event handling
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2009-11-19 07:13:16
Also in:
lkml
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
Keyboard input handler is multiplexing events form all keyboard-like devices in the system. Because of that per-device lock provided by input core is not enough to prevent clashes in ked_event() and we need our own lock to ensure that only one thread at a time executing kbd_event(). Signed-off-by: Dmitry Torokhov <redacted> --- drivers/char/keyboard.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index ce2ab67..e095ff3 100644
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c@@ -130,6 +130,7 @@ int shift_state = 0; */ static struct input_handler kbd_handler; +static DEFINE_SPINLOCK(kbd_event_lock); static unsigned long key_down[BITS_TO_LONGS(KEY_CNT)]; /* keyboard key bitmap */ static unsigned char shift_down[NR_SHIFT]; /* shift state counters.. */ static int dead_key_next;
@@ -1304,11 +1305,16 @@ static void kbd_keycode(unsigned int keycode, int down, int hw_raw) static void kbd_event(struct input_handle *handle, unsigned int event_type, unsigned int event_code, int value) { + /* We are called with interrupts disabled */ + spin_lock(&kbd_event_lock); + if (event_type == EV_MSC && event_code == MSC_RAW && HW_RAW(handle->dev)) kbd_rawcode(value); if (event_type == EV_KEY) kbd_keycode(event_code, value, HW_RAW(handle->dev)); + spin_unlock(&kbd_event_lock); + tasklet_schedule(&keyboard_tasklet); do_poke_blanked_console = 1; schedule_console_callback();
--
Dmitry