phonedev: cdev lock_kernel() pushdown
phone_open() looks OK, but I don't trust the subsidiary drivers (and ixj in
particular).
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/drivers/telephony/phonedev.c b/drivers/telephony/phonedev.c
index bcea8d9..4d74ba3 100644
--- a/drivers/telephony/phonedev.c
+++ b/drivers/telephony/phonedev.c
@@ -23,6 +23,7 @@
#include <linux/errno.h>
#include <linux/phonedev.h>
#include <linux/init.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <asm/system.h>
@@ -53,6 +54,7 @@
if (minor >= PHONE_NUM_DEVICES)
return -ENODEV;
+ lock_kernel();
mutex_lock(&phone_lock);
p = phone_device[minor];
if (p)
@@ -79,6 +81,7 @@
fops_put(old_fops);
end:
mutex_unlock(&phone_lock);
+ unlock_kernel();
return err;
}