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authorOliver Neukum <oliver@neukum.org>2010-01-13 17:33:15 +0300
committerGreg Kroah-Hartman <gregkh@suse.de>2010-03-03 01:54:23 +0300
commit86266452f80545285c14e20a8024f79c4fb88a86 (patch)
treeebb0a287f9bf189737d4924536d18b36492fd330 /drivers
parentf9de332ebf9df71892d52f7eb64af101a647349f (diff)
downloadlinux-86266452f80545285c14e20a8024f79c4fb88a86.tar.xz
USB: Push BKL on open down into the drivers
Straightforward push into the drivers to allow auditing individual drivers separately Signed-off-by: Oliver Neukum <oliver@neukum.org> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/hid/usbhid/hiddev.c7
-rw-r--r--drivers/media/video/dabusb.c8
-rw-r--r--drivers/staging/frontier/alphatrack.c3
-rw-r--r--drivers/staging/frontier/tranzport.c3
-rw-r--r--drivers/usb/class/cdc-wdm.c3
-rw-r--r--drivers/usb/class/usblp.c3
-rw-r--r--drivers/usb/class/usbtmc.c3
-rw-r--r--drivers/usb/core/file.c2
-rw-r--r--drivers/usb/image/mdc800.c3
-rw-r--r--drivers/usb/misc/adutux.c3
-rw-r--r--drivers/usb/misc/ftdi-elan.c15
-rw-r--r--drivers/usb/misc/idmouse.c8
-rw-r--r--drivers/usb/misc/iowarrior.c4
-rw-r--r--drivers/usb/misc/ldusb.c12
-rw-r--r--drivers/usb/misc/legousbtower.c3
-rw-r--r--drivers/usb/misc/rio500.c3
-rw-r--r--drivers/usb/misc/sisusbvga/sisusb.c14
-rw-r--r--drivers/usb/misc/usblcd.c5
-rw-r--r--drivers/usb/misc/vstusb.c9
-rw-r--r--drivers/usb/usb-skeleton.c3
20 files changed, 99 insertions, 15 deletions
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 867e08433e4b..433602aed468 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -265,9 +265,10 @@ static int hiddev_release(struct inode * inode, struct file * file)
static int hiddev_open(struct inode *inode, struct file *file)
{
struct hiddev_list *list;
- int res;
+ int res, i;
- int i = iminor(inode) - HIDDEV_MINOR_BASE;
+ lock_kernel();
+ i = iminor(inode) - HIDDEV_MINOR_BASE;
if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
return -ENODEV;
@@ -313,10 +314,12 @@ static int hiddev_open(struct inode *inode, struct file *file)
usbhid_open(hid);
}
+ unlock_kernel();
return 0;
bail:
file->private_data = NULL;
kfree(list);
+ unlock_kernel();
return res;
}
diff --git a/drivers/media/video/dabusb.c b/drivers/media/video/dabusb.c
index 9b413a35e048..0f505086774c 100644
--- a/drivers/media/video/dabusb.c
+++ b/drivers/media/video/dabusb.c
@@ -616,10 +616,12 @@ static int dabusb_open (struct inode *inode, struct file *file)
{
int devnum = iminor(inode);
pdabusb_t s;
+ int r;
if (devnum < DABUSB_MINOR || devnum >= (DABUSB_MINOR + NRDABUSB))
return -EIO;
+ lock_kernel();
s = &dabusb[devnum - DABUSB_MINOR];
dbg("dabusb_open");
@@ -634,6 +636,7 @@ static int dabusb_open (struct inode *inode, struct file *file)
msleep_interruptible(500);
if (signal_pending (current)) {
+ unlock_kernel();
return -EAGAIN;
}
mutex_lock(&s->mutex);
@@ -641,6 +644,7 @@ static int dabusb_open (struct inode *inode, struct file *file)
if (usb_set_interface (s->usbdev, _DABUSB_IF, 1) < 0) {
mutex_unlock(&s->mutex);
dev_err(&s->usbdev->dev, "set_interface failed\n");
+ unlock_kernel();
return -EINVAL;
}
s->opened = 1;
@@ -649,7 +653,9 @@ static int dabusb_open (struct inode *inode, struct file *file)
file->f_pos = 0;
file->private_data = s;
- return nonseekable_open(inode, file);
+ r = nonseekable_open(inode, file);
+ unlock_kernel();
+ return r;
}
static int dabusb_release (struct inode *inode, struct file *file)
diff --git a/drivers/staging/frontier/alphatrack.c b/drivers/staging/frontier/alphatrack.c
index 15aed87fe1bb..e2f82f0dbad8 100644
--- a/drivers/staging/frontier/alphatrack.c
+++ b/drivers/staging/frontier/alphatrack.c
@@ -41,6 +41,7 @@
#include <linux/mutex.h>
#include <linux/uaccess.h>
+#include <linux/smp_lock.h>
#include <linux/input.h>
#include <linux/usb.h>
#include <linux/poll.h>
@@ -325,6 +326,7 @@ static int usb_alphatrack_open(struct inode *inode, struct file *file)
int retval = 0;
struct usb_interface *interface;
+ lock_kernel();
nonseekable_open(inode, file);
subminor = iminor(inode);
@@ -394,6 +396,7 @@ unlock_exit:
unlock_disconnect_exit:
mutex_unlock(&disconnect_mutex);
+ unlock_kernel();
return retval;
}
diff --git a/drivers/staging/frontier/tranzport.c b/drivers/staging/frontier/tranzport.c
index ef8fcc8c67bd..1d3f7dc90f4f 100644
--- a/drivers/staging/frontier/tranzport.c
+++ b/drivers/staging/frontier/tranzport.c
@@ -40,6 +40,7 @@
#include <linux/mutex.h>
#include <linux/uaccess.h>
+#include <linux/smp_lock.h>
#include <linux/input.h>
#include <linux/usb.h>
#include <linux/poll.h>
@@ -343,6 +344,7 @@ static int usb_tranzport_open(struct inode *inode, struct file *file)
int retval = 0;
struct usb_interface *interface;
+ lock_kernel();
nonseekable_open(inode, file);
subminor = iminor(inode);
@@ -413,6 +415,7 @@ unlock_exit:
unlock_disconnect_exit:
mutex_unlock(&disconnect_mutex);
+ unlock_kernel();
return retval;
}
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index 18aafcb08fc8..b75a3d8bb02f 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -19,6 +19,7 @@
#include <linux/uaccess.h>
#include <linux/bitops.h>
#include <linux/poll.h>
+#include <linux/smp_lock.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <asm/byteorder.h>
@@ -516,6 +517,7 @@ static int wdm_open(struct inode *inode, struct file *file)
struct usb_interface *intf;
struct wdm_device *desc;
+ lock_kernel();
mutex_lock(&wdm_mutex);
intf = usb_find_interface(&wdm_driver, minor);
if (!intf)
@@ -548,6 +550,7 @@ static int wdm_open(struct inode *inode, struct file *file)
usb_autopm_put_interface(desc->intf);
out:
mutex_unlock(&wdm_mutex);
+ unlock_kernel();
return rv;
}
diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index 93b5f85d7ceb..d53f9499f936 100644
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -56,6 +56,7 @@
#include <linux/slab.h>
#include <linux/lp.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#undef DEBUG
#include <linux/usb.h>
@@ -395,6 +396,7 @@ static int usblp_open(struct inode *inode, struct file *file)
if (minor < 0)
return -ENODEV;
+ lock_kernel();
mutex_lock (&usblp_mutex);
retval = -ENODEV;
@@ -434,6 +436,7 @@ static int usblp_open(struct inode *inode, struct file *file)
}
out:
mutex_unlock (&usblp_mutex);
+ unlock_kernel();
return retval;
}
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 8588c0937a89..426bfc72b9b4 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -26,6 +26,7 @@
#include <linux/uaccess.h>
#include <linux/kref.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <linux/usb.h>
#include <linux/usb/tmc.h>
@@ -113,6 +114,7 @@ static int usbtmc_open(struct inode *inode, struct file *filp)
struct usbtmc_device_data *data;
int retval = 0;
+ lock_kernel();
intf = usb_find_interface(&usbtmc_driver, iminor(inode));
if (!intf) {
printk(KERN_ERR KBUILD_MODNAME
@@ -128,6 +130,7 @@ static int usbtmc_open(struct inode *inode, struct file *filp)
filp->private_data = data;
exit:
+ unlock_kernel();
return retval;
}
diff --git a/drivers/usb/core/file.c b/drivers/usb/core/file.c
index bfc6c2eea647..c3536f151f02 100644
--- a/drivers/usb/core/file.c
+++ b/drivers/usb/core/file.c
@@ -34,7 +34,6 @@ static int usb_open(struct inode * inode, struct file * file)
int err = -ENODEV;
const struct file_operations *old_fops, *new_fops = NULL;
- lock_kernel();
down_read(&minor_rwsem);
c = usb_minors[minor];
@@ -53,7 +52,6 @@ static int usb_open(struct inode * inode, struct file * file)
fops_put(old_fops);
done:
up_read(&minor_rwsem);
- unlock_kernel();
return err;
}
diff --git a/drivers/usb/image/mdc800.c b/drivers/usb/image/mdc800.c
index e192e8f7c560..dce4f7b69ac3 100644
--- a/drivers/usb/image/mdc800.c
+++ b/drivers/usb/image/mdc800.c
@@ -96,6 +96,7 @@
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <linux/usb.h>
#include <linux/fs.h>
@@ -622,6 +623,7 @@ static int mdc800_device_open (struct inode* inode, struct file *file)
int retval=0;
int errn=0;
+ lock_kernel();
mutex_lock(&mdc800->io_lock);
if (mdc800->state == NOT_CONNECTED)
@@ -660,6 +662,7 @@ static int mdc800_device_open (struct inode* inode, struct file *file)
error_out:
mutex_unlock(&mdc800->io_lock);
+ unlock_kernel();
return errn;
}
diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 306e97825b36..ac8ad91c2dac 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -25,6 +25,7 @@
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#ifdef CONFIG_USB_DEBUG
@@ -274,6 +275,7 @@ static int adu_open(struct inode *inode, struct file *file)
dbg(2,"%s : enter", __func__);
+ lock_kernel();
subminor = iminor(inode);
if ((retval = mutex_lock_interruptible(&adutux_mutex))) {
@@ -332,6 +334,7 @@ static int adu_open(struct inode *inode, struct file *file)
exit_no_device:
mutex_unlock(&adutux_mutex);
exit_no_lock:
+ unlock_kernel();
dbg(2,"%s : leave, return value %d ", __func__, retval);
return retval;
}
diff --git a/drivers/usb/misc/ftdi-elan.c b/drivers/usb/misc/ftdi-elan.c
index f21bf5160f83..32c47fbee288 100644
--- a/drivers/usb/misc/ftdi-elan.c
+++ b/drivers/usb/misc/ftdi-elan.c
@@ -45,6 +45,7 @@
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/workqueue.h>
@@ -623,22 +624,30 @@ static void ftdi_elan_status_work(struct work_struct *work)
*/
static int ftdi_elan_open(struct inode *inode, struct file *file)
{
- int subminor = iminor(inode);
- struct usb_interface *interface = usb_find_interface(&ftdi_elan_driver,
- subminor);
+ int subminor;
+ struct usb_interface *interface;
+
+ lock_kernel();
+ subminor = iminor(inode);
+ interface = usb_find_interface(&ftdi_elan_driver, subminor);
+
if (!interface) {
+ unlock_kernel();
printk(KERN_ERR "can't find device for minor %d\n", subminor);
return -ENODEV;
} else {
struct usb_ftdi *ftdi = usb_get_intfdata(interface);
if (!ftdi) {
+ unlock_kernel();
return -ENODEV;
} else {
if (down_interruptible(&ftdi->sw_lock)) {
+ unlock_kernel();
return -EINTR;
} else {
ftdi_elan_get_kref(ftdi);
file->private_data = ftdi;
+ unlock_kernel();
return 0;
}
}
diff --git a/drivers/usb/misc/idmouse.c b/drivers/usb/misc/idmouse.c
index a54c3cb804ce..68df9ac76699 100644
--- a/drivers/usb/misc/idmouse.c
+++ b/drivers/usb/misc/idmouse.c
@@ -24,6 +24,7 @@
#include <linux/module.h>
#include <linux/completion.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
@@ -226,16 +227,20 @@ static int idmouse_open(struct inode *inode, struct file *file)
struct usb_interface *interface;
int result;
+ lock_kernel();
/* get the interface from minor number and driver information */
interface = usb_find_interface (&idmouse_driver, iminor (inode));
- if (!interface)
+ if (!interface) {
+ unlock_kernel();
return -ENODEV;
+ }
mutex_lock(&open_disc_mutex);
/* get the device information block from the interface */
dev = usb_get_intfdata(interface);
if (!dev) {
mutex_unlock(&open_disc_mutex);
+ unlock_kernel();
return -ENODEV;
}
@@ -272,6 +277,7 @@ error:
/* unlock this device */
mutex_unlock(&dev->lock);
+ unlock_kernel();
return result;
}
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index 5206423211fb..d3c852363883 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -602,10 +602,12 @@ static int iowarrior_open(struct inode *inode, struct file *file)
dbg("%s", __func__);
+ lock_kernel();
subminor = iminor(inode);
interface = usb_find_interface(&iowarrior_driver, subminor);
if (!interface) {
+ unlock_kernel();
err("%s - error, can't find device for minor %d", __func__,
subminor);
return -ENODEV;
@@ -615,6 +617,7 @@ static int iowarrior_open(struct inode *inode, struct file *file)
dev = usb_get_intfdata(interface);
if (!dev) {
mutex_unlock(&iowarrior_open_disc_lock);
+ unlock_kernel();
return -ENODEV;
}
@@ -641,6 +644,7 @@ static int iowarrior_open(struct inode *inode, struct file *file)
out:
mutex_unlock(&dev->mutex);
+ unlock_kernel();
return retval;
}
diff --git a/drivers/usb/misc/ldusb.c b/drivers/usb/misc/ldusb.c
index 7c0bd13eccb2..8de32df5978a 100644
--- a/drivers/usb/misc/ldusb.c
+++ b/drivers/usb/misc/ldusb.c
@@ -33,6 +33,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <linux/input.h>
@@ -296,12 +297,14 @@ static int ld_usb_open(struct inode *inode, struct file *file)
int retval;
struct usb_interface *interface;
+ lock_kernel();
nonseekable_open(inode, file);
subminor = iminor(inode);
interface = usb_find_interface(&ld_usb_driver, subminor);
if (!interface) {
+ unlock_kernel();
err("%s - error, can't find device for minor %d\n",
__func__, subminor);
return -ENODEV;
@@ -309,12 +312,16 @@ static int ld_usb_open(struct inode *inode, struct file *file)
dev = usb_get_intfdata(interface);
- if (!dev)
+ if (!dev) {
+ unlock_kernel();
return -ENODEV;
+ }
/* lock this device */
- if (mutex_lock_interruptible(&dev->mutex))
+ if (mutex_lock_interruptible(&dev->mutex)) {
+ unlock_kernel();
return -ERESTARTSYS;
+ }
/* allow opening only once */
if (dev->open_count) {
@@ -353,6 +360,7 @@ static int ld_usb_open(struct inode *inode, struct file *file)
unlock_exit:
mutex_unlock(&dev->mutex);
+ unlock_kernel();
return retval;
}
diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
index 3d4378fb4410..94e1b84134dd 100644
--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -82,6 +82,7 @@
#include <linux/module.h>
#include <linux/completion.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/poll.h>
@@ -345,6 +346,7 @@ static int tower_open (struct inode *inode, struct file *file)
dbg(2, "%s: enter", __func__);
+ lock_kernel();
nonseekable_open(inode, file);
subminor = iminor(inode);
@@ -430,6 +432,7 @@ unlock_exit:
mutex_unlock(&dev->lock);
exit:
+ unlock_kernel();
dbg(2, "%s: leave, return value %d ", __func__, retval);
return retval;
diff --git a/drivers/usb/misc/rio500.c b/drivers/usb/misc/rio500.c
index 17e4eecaee73..47ce46bb5b01 100644
--- a/drivers/usb/misc/rio500.c
+++ b/drivers/usb/misc/rio500.c
@@ -77,7 +77,7 @@ static struct rio_usb_data rio_instance;
static int open_rio(struct inode *inode, struct file *file)
{
struct rio_usb_data *rio = &rio_instance;
-
+ lock_kernel();
mutex_lock(&(rio->lock));
if (rio->isopen || !rio->present) {
@@ -91,6 +91,7 @@ static int open_rio(struct inode *inode, struct file *file)
mutex_unlock(&(rio->lock));
dev_info(&rio->rio_dev->dev, "Rio opened.\n");
+ unlock_kernel();
return 0;
}
diff --git a/drivers/usb/misc/sisusbvga/sisusb.c b/drivers/usb/misc/sisusbvga/sisusb.c
index bb0b315b521d..3991655f8f09 100644
--- a/drivers/usb/misc/sisusbvga/sisusb.c
+++ b/drivers/usb/misc/sisusbvga/sisusb.c
@@ -2416,21 +2416,28 @@ sisusb_open(struct inode *inode, struct file *file)
struct usb_interface *interface;
int subminor = iminor(inode);
- if (!(interface = usb_find_interface(&sisusb_driver, subminor)))
+ lock_kernel();
+ if (!(interface = usb_find_interface(&sisusb_driver, subminor))) {
+ unlock_kernel();
return -ENODEV;
+ }
- if (!(sisusb = usb_get_intfdata(interface)))
+ if (!(sisusb = usb_get_intfdata(interface))) {
+ unlock_kernel();
return -ENODEV;
+ }
mutex_lock(&sisusb->lock);
if (!sisusb->present || !sisusb->ready) {
mutex_unlock(&sisusb->lock);
+ unlock_kernel();
return -ENODEV;
}
if (sisusb->isopen) {
mutex_unlock(&sisusb->lock);
+ unlock_kernel();
return -EBUSY;
}
@@ -2439,11 +2446,13 @@ sisusb_open(struct inode *inode, struct file *file)
if (sisusb_init_gfxdevice(sisusb, 0)) {
mutex_unlock(&sisusb->lock);
dev_err(&sisusb->sisusb_dev->dev, "Failed to initialize device\n");
+ unlock_kernel();
return -EIO;
}
} else {
mutex_unlock(&sisusb->lock);
dev_err(&sisusb->sisusb_dev->dev, "Device not attached to USB 2.0 hub\n");
+ unlock_kernel();
return -EIO;
}
}
@@ -2456,6 +2465,7 @@ sisusb_open(struct inode *inode, struct file *file)
file->private_data = sisusb;
mutex_unlock(&sisusb->lock);
+ unlock_kernel();
return 0;
}
diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c
index 499d7508be9a..90aede90553e 100644
--- a/drivers/usb/misc/usblcd.c
+++ b/drivers/usb/misc/usblcd.c
@@ -74,10 +74,12 @@ static int lcd_open(struct inode *inode, struct file *file)
struct usb_interface *interface;
int subminor, r;
+ lock_kernel();
subminor = iminor(inode);
interface = usb_find_interface(&lcd_driver, subminor);
if (!interface) {
+ unlock_kernel();
err ("USBLCD: %s - error, can't find device for minor %d",
__func__, subminor);
return -ENODEV;
@@ -87,6 +89,7 @@ static int lcd_open(struct inode *inode, struct file *file)
dev = usb_get_intfdata(interface);
if (!dev) {
mutex_unlock(&open_disc_mutex);
+ unlock_kernel();
return -ENODEV;
}
@@ -98,11 +101,13 @@ static int lcd_open(struct inode *inode, struct file *file)
r = usb_autopm_get_interface(interface);
if (r < 0) {
kref_put(&dev->kref, lcd_delete);
+ unlock_kernel();
return r;
}
/* save our object in the file's private structure */
file->private_data = dev;
+ unlock_kernel();
return 0;
}
diff --git a/drivers/usb/misc/vstusb.c b/drivers/usb/misc/vstusb.c
index 874c81bb27b9..b787b25d4cc4 100644
--- a/drivers/usb/misc/vstusb.c
+++ b/drivers/usb/misc/vstusb.c
@@ -27,6 +27,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/smp_lock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
@@ -103,19 +104,23 @@ static int vstusb_open(struct inode *inode, struct file *file)
struct vstusb_device *vstdev;
struct usb_interface *interface;
+ lock_kernel();
interface = usb_find_interface(&vstusb_driver, iminor(inode));
if (!interface) {
printk(KERN_ERR KBUILD_MODNAME
": %s - error, can't find device for minor %d\n",
__func__, iminor(inode));
+ unlock_kernel();
return -ENODEV;
}
vstdev = usb_get_intfdata(interface);
- if (!vstdev)
+ if (!vstdev) {
+ unlock_kernel();
return -ENODEV;
+ }
/* lock this device */
mutex_lock(&vstdev->lock);
@@ -123,6 +128,7 @@ static int vstusb_open(struct inode *inode, struct file *file)
/* can only open one time */
if ((!vstdev->present) || (vstdev->isopen)) {
mutex_unlock(&vstdev->lock);
+ unlock_kernel();
return -EBUSY;
}
@@ -137,6 +143,7 @@ static int vstusb_open(struct inode *inode, struct file *file)
dev_dbg(&vstdev->usb_dev->dev, "%s: opened\n", __func__);
mutex_unlock(&vstdev->lock);
+ unlock_kernel();
return 0;
}
diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c
index 61522787f39c..e94176bfd272 100644
--- a/drivers/usb/usb-skeleton.c
+++ b/drivers/usb/usb-skeleton.c
@@ -18,6 +18,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
+#include <linux/smp_lock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/mutex.h>
@@ -90,6 +91,7 @@ static int skel_open(struct inode *inode, struct file *file)
int subminor;
int retval = 0;
+ lock_kernel();
subminor = iminor(inode);
interface = usb_find_interface(&skel_driver, subminor);
@@ -135,6 +137,7 @@ static int skel_open(struct inode *inode, struct file *file)
mutex_unlock(&dev->io_mutex);
exit:
+ unlock_kernel();
return retval;
}