On Fri, Apr 05, 2013 at 06:09:44PM +0200, Hector Palacios wrote:
> A watchdog device may be stopped from userspace using WDIOC_SETOPTIONS
> ioctl and flag WDIOS_DISABLECARD. If the device is closed after this
> operation, watchdog_release() is called and status bits checked for
> stopping it. Besides, if the device has not been unregistered a critical
> message "watchdog did not stop!" is printed, although the ioctl may have
> successfully stopped it already.
>
> Without the patch a user application sample code like this will successfully
> stop the watchdog, but the kernel will output the message
> "watchdog did not stop!":
>
> wd_fd = open("/dev/watchdog", O_RDWR);
>
> flags = WDIOS_DISABLECARD;
> ioctl(wd_fd, WDIOC_SETOPTIONS, &flags);
>
> close(wd_fd);
>
> Signed-off-by: Hector Palacios <hector.palac...@digi.com>
How about the following patch instead ?
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 08b48bb..9775e8d 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -469,7 +469,9 @@ static int watchdog_release(struct inode *inode, struct
file *file)
* or if WDIOF_MAGICCLOSE is not set. If nowayout was set then
* watchdog_stop will fail.
*/
- if (test_and_clear_bit(WDOG_ALLOW_RELEASE, &wdd->status) ||
+ if (!test_bit(WDOG_ACTIVE, &wdd->status))
+ err = 0;
+ else if (test_and_clear_bit(WDOG_ALLOW_RELEASE, &wdd->status) ||
!(wdd->info->options & WDIOF_MAGICCLOSE))
err = watchdog_stop(wdd);
Much less invasive and the result is the same.
Thanks,
Guenter
> ---
> drivers/watchdog/watchdog_dev.c | 38 +++++++++++++++++++++-----------------
> 1 file changed, 21 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
> index ef8edec..adadbdd 100644
> --- a/drivers/watchdog/watchdog_dev.c
> +++ b/drivers/watchdog/watchdog_dev.c
> @@ -463,24 +463,28 @@ out:
> static int watchdog_release(struct inode *inode, struct file *file)
> {
> struct watchdog_device *wdd = file->private_data;
> - int err = -EBUSY;
>
> - /*
> - * We only stop the watchdog if we received the magic character
> - * or if WDIOF_MAGICCLOSE is not set. If nowayout was set then
> - * watchdog_stop will fail.
> - */
> - if (test_and_clear_bit(WDOG_ALLOW_RELEASE, &wdd->status) ||
> - !(wdd->info->options & WDIOF_MAGICCLOSE))
> - err = watchdog_stop(wdd);
> -
> - /* If the watchdog was not stopped, send a keepalive ping */
> - if (err < 0) {
> - mutex_lock(&wdd->lock);
> - if (!test_bit(WDOG_UNREGISTERED, &wdd->status))
> - dev_crit(wdd->dev, "watchdog did not stop!\n");
> - mutex_unlock(&wdd->lock);
> - watchdog_ping(wdd);
> + if (test_bit(WDOG_ACTIVE, &wdd->status)) {
> + int err = -EBUSY;
> +
> + /*
> + * We only stop the watchdog if we received the magic character
> + * or if WDIOF_MAGICCLOSE is not set. If nowayout was set then
> + * watchdog_stop will fail.
> + */
> + if (test_and_clear_bit(WDOG_ALLOW_RELEASE, &wdd->status) ||
> + !(wdd->info->options & WDIOF_MAGICCLOSE)) {
> + err = watchdog_stop(wdd);
> + }
> +
> + /* If the watchdog was not stopped, send a keepalive ping */
> + if (err < 0) {
> + mutex_lock(&wdd->lock);
> + if (!test_bit(WDOG_UNREGISTERED, &wdd->status))
> + dev_crit(wdd->dev, "watchdog did not stop!\n");
> + mutex_unlock(&wdd->lock);
> + watchdog_ping(wdd);
> + }
> }
>
> /* Allow the owner module to be unloaded again */
> --
> 1.7.9.5
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