Re: Oops in pwc v4l driver

From: Mauro Carvalho Chehab
Date: Wed Sep 26 2007 - 09:09:07 EST


Hi Oliver,

May you send your Signed-off-by for the patch?

Cheers,
Mauro.

Em Dom, 2007-09-02 Ãs 15:02 +0200, Oliver Neukum escreveu:
> Am Sonntag 02 September 2007 schrieb Alex Smith:
> > Hi,
> >
> > I found an old Philips Askey VC010 webcam and attempted to get it
> > working on Linux (latest git, x86_64). It worked fine, I could view
> > the camera in mplayer. But, however, when I went to move the camera, I
> > unplugged it and forgot to close mplayer. I didn't notice, moved it,
>
> Yes,
>
> this is a known issue. This patch should fix it. Does it work for you?
>
> Regards
> Oliver
> ---
>
> --- a/drivers/media/video/pwc/pwc-if.c 2007-08-24 10:16:38.000000000 +0200
> +++ b/drivers/media/video/pwc/pwc-if.c 2007-08-24 11:01:26.000000000 +0200
> @@ -908,31 +908,49 @@ int pwc_isoc_init(struct pwc_device *pde
> return 0;
> }
>
> -void pwc_isoc_cleanup(struct pwc_device *pdev)
> +static void pwc_iso_stop(struct pwc_device *pdev)
> {
> int i;
>
> - PWC_DEBUG_OPEN(">> pwc_isoc_cleanup()\n");
> - if (pdev == NULL)
> - return;
> - if (pdev->iso_init == 0)
> - return;
> -
> /* Unlinking ISOC buffers one by one */
> for (i = 0; i < MAX_ISO_BUFS; i++) {
> struct urb *urb;
>
> urb = pdev->sbuf[i].urb;
> if (urb != 0) {
> - if (pdev->iso_init) {
> - PWC_DEBUG_MEMORY("Unlinking URB %p\n", urb);
> - usb_kill_urb(urb);
> - }
> + PWC_DEBUG_MEMORY("Unlinking URB %p\n", urb);
> + usb_kill_urb(urb);
> + }
> + }
> +}
> +
> +static void pwc_iso_free(struct pwc_device *pdev)
> +{
> + int i;
> +
> + /* Freeing ISOC buffers one by one */
> + for (i = 0; i < MAX_ISO_BUFS; i++) {
> + struct urb *urb;
> +
> + urb = pdev->sbuf[i].urb;
> + if (urb != 0) {
> PWC_DEBUG_MEMORY("Freeing URB\n");
> usb_free_urb(urb);
> pdev->sbuf[i].urb = NULL;
> }
> }
> +}
> +
> +void pwc_isoc_cleanup(struct pwc_device *pdev)
> +{
> + PWC_DEBUG_OPEN(">> pwc_isoc_cleanup()\n");
> + if (pdev == NULL)
> + return;
> + if (pdev->iso_init == 0)
> + return;
> +
> + pwc_iso_stop(pdev);
> + pwc_iso_free(pdev);
>
> /* Stop camera, but only if we are sure the camera is still there (unplug
> is signalled by EPIPE)
> @@ -1212,6 +1230,7 @@ static int pwc_video_close(struct inode
>
> PWC_DEBUG_OPEN(">> video_close called(vdev = 0x%p).\n", vdev);
>
> + lock_kernel();
> pdev = (struct pwc_device *)vdev->priv;
> if (pdev->vopen == 0)
> PWC_DEBUG_MODULE("video_close() called on closed device?\n");
> @@ -1231,7 +1250,6 @@ static int pwc_video_close(struct inode
> pwc_isoc_cleanup(pdev);
> pwc_free_buffers(pdev);
>
> - lock_kernel();
> /* Turn off LEDS and power down camera, but only when not unplugged */
> if (!pdev->unplugged) {
> /* Turn LEDs off */
> @@ -1277,7 +1295,7 @@ static ssize_t pwc_video_read(struct fil
> struct pwc_device *pdev;
> int noblock = file->f_flags & O_NONBLOCK;
> DECLARE_WAITQUEUE(wait, current);
> - int bytes_to_read;
> + int bytes_to_read, rv = 0;
> void *image_buffer_addr;
>
> PWC_DEBUG_READ("pwc_video_read(vdev=0x%p, buf=%p, count=%zd) called.\n",
> @@ -1287,8 +1305,12 @@ static ssize_t pwc_video_read(struct fil
> pdev = vdev->priv;
> if (pdev == NULL)
> return -EFAULT;
> - if (pdev->error_status)
> - return -pdev->error_status; /* Something happened, report what. */
> +
> + mutex_lock(&pdev->modlock);
> + if (pdev->error_status) {
> + rv = -pdev->error_status; /* Something happened, report what. */
> + goto err_out;
> + }
>
> /* In case we're doing partial reads, we don't have to wait for a frame */
> if (pdev->image_read_pos == 0) {
> @@ -1299,17 +1321,20 @@ static ssize_t pwc_video_read(struct fil
> if (pdev->error_status) {
> remove_wait_queue(&pdev->frameq, &wait);
> set_current_state(TASK_RUNNING);
> - return -pdev->error_status ;
> + rv = -pdev->error_status ;
> + goto err_out;
> }
> if (noblock) {
> remove_wait_queue(&pdev->frameq, &wait);
> set_current_state(TASK_RUNNING);
> - return -EWOULDBLOCK;
> + rv = -EWOULDBLOCK;
> + goto err_out;
> }
> if (signal_pending(current)) {
> remove_wait_queue(&pdev->frameq, &wait);
> set_current_state(TASK_RUNNING);
> - return -ERESTARTSYS;
> + rv = -ERESTARTSYS;
> + goto err_out;
> }
> schedule();
> set_current_state(TASK_INTERRUPTIBLE);
> @@ -1318,8 +1343,10 @@ static ssize_t pwc_video_read(struct fil
> set_current_state(TASK_RUNNING);
>
> /* Decompress and release frame */
> - if (pwc_handle_frame(pdev))
> - return -EFAULT;
> + if (pwc_handle_frame(pdev)) {
> + rv = -EFAULT;
> + goto err_out;
> + }
> }
>
> PWC_DEBUG_READ("Copying data to user space.\n");
> @@ -1334,14 +1361,20 @@ static ssize_t pwc_video_read(struct fil
> image_buffer_addr = pdev->image_data;
> image_buffer_addr += pdev->images[pdev->fill_image].offset;
> image_buffer_addr += pdev->image_read_pos;
> - if (copy_to_user(buf, image_buffer_addr, count))
> - return -EFAULT;
> + if (copy_to_user(buf, image_buffer_addr, count)) {
> + rv = -EFAULT;
> + goto err_out;
> + }
> pdev->image_read_pos += count;
> if (pdev->image_read_pos >= bytes_to_read) { /* All data has been read */
> pdev->image_read_pos = 0;
> pwc_next_image(pdev);
> }
> + mutex_unlock(&pdev->modlock);
> return count;
> +err_out:
> + mutex_unlock(&pdev->modlock);
> + return rv;
> }
>
> static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
> @@ -1367,7 +1400,20 @@ static unsigned int pwc_video_poll(struc
> static int pwc_video_ioctl(struct inode *inode, struct file *file,
> unsigned int cmd, unsigned long arg)
> {
> - return video_usercopy(inode, file, cmd, arg, pwc_video_do_ioctl);
> + struct video_device *vdev = file->private_data;
> + struct pwc_device *pdev;
> + int r = -ENODEV;
> +
> + if (!vdev)
> + goto out;
> + pdev = vdev->priv;
> +
> + mutex_lock(&pdev->modlock);
> + if (!pdev->unplugged)
> + r = video_usercopy(inode, file, cmd, arg, pwc_video_do_ioctl);
> + mutex_unlock(&pdev->modlock);
> +out:
> + return r;
> }
>
> static int pwc_video_mmap(struct file *file, struct vm_area_struct *vma)
> @@ -1810,7 +1856,10 @@ static void usb_pwc_disconnect(struct us
> wake_up_interruptible(&pdev->frameq);
> /* Wait until device is closed */
> if(pdev->vopen) {
> + mutex_lock(&pdev->modlock);
> pdev->unplugged = 1;
> + mutex_unlock(&pdev->modlock);
> + pwc_iso_stop(pdev);
> } else {
> /* Device is closed, so we can safely unregister it */
> PWC_DEBUG_PROBE("Unregistering video device in disconnect().\n");
> @@ -1828,7 +1877,6 @@ disconnect_out:
> unlock_kernel();
> }
>
> -
> /* *grunt* We have to do atoi ourselves :-( */
> static int pwc_atoi(const char *s)
> {
> -
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--
Cheers,
Mauro

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