diff options
Diffstat (limited to 'drivers/char/briq_panel.c')
| -rw-r--r-- | drivers/char/briq_panel.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/char/briq_panel.c b/drivers/char/briq_panel.c index b6f2639f903..d8cff909001 100644 --- a/drivers/char/briq_panel.c +++ b/drivers/char/briq_panel.c @@ -6,6 +6,7 @@ #include <linux/module.h> +#include <linux/smp_lock.h> #include <linux/types.h> #include <linux/errno.h> #include <linux/tty.h> @@ -67,11 +68,15 @@ static void set_led(char state) static int briq_panel_open(struct inode *ino, struct file *filep) { - /* enforce single access */ - if (vfd_is_open) + lock_kernel(); + /* enforce single access, vfd_is_open is protected by BKL */ + if (vfd_is_open) { + unlock_kernel(); return -EBUSY; + } vfd_is_open = 1; + unlock_kernel(); return 0; } |