Add a bunch of cycle_kernel_lock() calls

All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization.  So make those functions acquire then release the BKL to be
on the safe side.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/char/scx200_gpio.c b/drivers/char/scx200_gpio.c
index be2c623a9862..1d9100561c8a 100644
--- a/drivers/char/scx200_gpio.c
+++ b/drivers/char/scx200_gpio.c
@@ -12,6 +12,7 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
+#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
 
@@ -46,12 +47,12 @@ struct nsc_gpio_ops scx200_gpio_ops = {
 };
 EXPORT_SYMBOL_GPL(scx200_gpio_ops);
 
-/* No BKL needed here: no global resources used */
 static int scx200_gpio_open(struct inode *inode, struct file *file)
 {
         unsigned m = iminor(inode);
         file->private_data = &scx200_gpio_ops;
 
+        cycle_kernel_lock();
         if (m >= MAX_PINS)
                 return -EINVAL;
         return nonseekable_open(inode, file);