[8/8] usb_pcwd: remove superfluous usb_device pointer
Commit Message
Retrieve the device from the interface
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/watchdog/pcwd_usb.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
Comments
Hi Oliver,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Oliver-Neukum/pcwd_usb-stop-open-race-disconnect/20230427-223413
base: linus/master
patch link: https://lore.kernel.org/r/20230427133350.31064-9-oneukum%40suse.com
patch subject: [PATCH 8/8] usb_pcwd: remove superfluous usb_device pointer
config: parisc-randconfig-m041-20230509 (https://download.01.org/0day-ci/archive/20230512/202305122231.n8RlGMhT-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 12.1.0
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Link: https://lore.kernel.org/r/202305122231.n8RlGMhT-lkp@intel.com/
smatch warnings:
drivers/watchdog/pcwd_usb.c:215 usb_pcwd_send_command() warn: variable dereferenced before check 'usb_pcwd' (see line 211)
vim +/usb_pcwd +215 drivers/watchdog/pcwd_usb.c
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 206 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 207 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 208 {
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 209 int got_response, count;
5412df0bda90a2 drivers/watchdog/pcwd_usb.c Guenter Roeck 2013-10-14 210 unsigned char *buf;
41b4f0869562d7 drivers/watchdog/pcwd_usb.c Oliver Neukum 2023-04-27 @211 struct usb_device *udev = interface_to_usbdev(usb_pcwd->interface);
^^^^^^^^^^
Dereference.
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 212
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 213 /* We will not send any commands if the USB PCWD device does
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 214 * not exist */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 @215 if ((!usb_pcwd) || (!usb_pcwd->exists))
^^^^^^^^^^^
Checked too late.
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 216 return -1;
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 217
5412df0bda90a2 drivers/watchdog/pcwd_usb.c Guenter Roeck 2013-10-14 218 buf = kmalloc(6, GFP_KERNEL);
5412df0bda90a2 drivers/watchdog/pcwd_usb.c Guenter Roeck 2013-10-14 219 if (buf == NULL)
5412df0bda90a2 drivers/watchdog/pcwd_usb.c Guenter Roeck 2013-10-14 220 return 0;
5412df0bda90a2 drivers/watchdog/pcwd_usb.c Guenter Roeck 2013-10-14 221
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 222 /* The USB PC Watchdog uses a 6 byte report format.
143a2e54bf5321 drivers/watchdog/pcwd_usb.c Wim Van Sebroeck 2009-03-18 223 * The board currently uses only 3 of the six bytes of the report. */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 224 buf[0] = cmd; /* Byte 0 = CMD */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 225 buf[1] = *msb; /* Byte 1 = Data MSB */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 226 buf[2] = *lsb; /* Byte 2 = Data LSB */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 227 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */
^1da177e4c3f41 drivers/char/watchdog/pcwd_usb.c Linus Torvalds 2005-04-16 228
d7e92f7f768477 drivers/watchdog/pcwd_usb.c Greg Kroah-Hartman 2013-12-19 229 dev_dbg(&usb_pcwd->interface->dev,
@@ -112,8 +112,6 @@ static char expect_release;
/* Structure to hold all of our device specific stuff */
struct usb_pcwd_private {
- /* save off the usb device pointer */
- struct usb_device *udev;
/* the interface for this device */
struct usb_interface *interface;
@@ -210,6 +208,7 @@ static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
{
int got_response, count;
unsigned char *buf;
+ struct usb_device *udev = interface_to_usbdev(usb_pcwd->interface);
/* We will not send any commands if the USB PCWD device does
* not exist */
@@ -233,7 +232,7 @@ static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
atomic_set(&usb_pcwd->cmd_received, 0);
- if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
+ if (usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
HID_REQ_SET_REPORT, HID_DT_REPORT,
0x0200, usb_pcwd->interface_number, buf, 6,
USB_COMMAND_TIMEOUT) != 6) {
@@ -625,8 +624,10 @@ static struct notifier_block usb_pcwd_notifier = {
*/
static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
{
+ struct usb_device *udev = interface_to_usbdev(usb_pcwd->interface);
+
usb_free_urb(usb_pcwd->intr_urb);
- usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
+ usb_free_coherent(udev, usb_pcwd->intr_size,
usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
kfree(usb_pcwd);
}
@@ -691,7 +692,6 @@ static int usb_pcwd_probe(struct usb_interface *interface,
usb_pcwd_device = usb_pcwd;
mutex_init(&usb_pcwd->mtx);
- usb_pcwd->udev = udev;
usb_pcwd->interface = interface;
usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?