From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Thu, 5 Jan 2017 17:14:16 +0000 (+0900)
Subject: sysrq: attach sysrq handler correctly for 32-bit kernel
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=802c03881f29844af0252b6e22be5d2f65f93fd0;p=linux-beck.git

sysrq: attach sysrq handler correctly for 32-bit kernel

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@suse.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 52bbd27e93ae..701c085bb19b 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -946,8 +946,8 @@ static const struct input_device_id sysrq_ids[] = {
 	{
 		.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) },
 	},
 	{ },
 };