[PATCH 4.9 069/120] sysrq: attach sysrq handler correctly for 32-bit kernel
From: Greg Kroah-Hartman
Date:  Wed Jan 18 2017 - 05:54:49 EST
4.9-stable review patch.  If anyone has any objections, please let me know.
------------------
From: Akinobu Mita <akinobu.mita@xxxxxxxxx>
commit 802c03881f29844af0252b6e22be5d2f65f93fd0 upstream.
The sysrq input handler should be attached to the input device which has
a left alt key.
On 32-bit kernels, some input devices which has a left alt key cannot
attach sysrq handler.  Because the keybit bitmap in struct input_device_id
for sysrq is not correctly initialized.  KEY_LEFTALT is 56 which is
greater than BITS_PER_LONG on 32-bit kernels.
I found this problem when using a matrix keypad device which defines
a KEY_LEFTALT (56) but doesn't have a KEY_O (24 == 56%32).
Cc: Jiri Slaby <jslaby@xxxxxxxx>
Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Acked-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/tty/sysrq.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -946,8 +946,8 @@ static const struct input_device_id sysr
 	{
 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 				INPUT_DEVICE_ID_MATCH_KEYBIT,
-		.evbit = { BIT_MASK(EV_KEY) },
-		.keybit = { BIT_MASK(KEY_LEFTALT) },
+		.evbit = { [BIT_WORD(EV_KEY)] = BIT_MASK(EV_KEY) },
+		.keybit = { [BIT_WORD(KEY_LEFTALT)] = BIT_MASK(KEY_LEFTALT) },
 	},
 	{ },
 };