@@ -269,19 +269,14 @@ static int evdev_flush(struct file *file, fl_owner_t id)
{
struct evdev_client *client = file->private_data;
struct evdev *evdev = client->evdev;
- int retval;
- retval = mutex_lock_interruptible(&evdev->mutex);
- if (retval)
- return retval;
+ mutex_lock(&evdev->mutex);
- if (!evdev->exist || client->revoked)
- retval = -ENODEV;
- else
- retval = input_flush_device(&evdev->handle, file);
+ if (evdev->exist && !client->revoked)
+ input_flush_device(&evdev->handle, file);
mutex_unlock(&evdev->mutex);
- return retval;
+ return 0;
}
static void evdev_free(struct device *dev)
This is a note to let you know that I have just added a patch titled Input: evdev - do not report errors form flush() to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt8. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 147f86f94c3e14ca54ff1aef210d536d9c1c7021 Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@suse.de> Date: Thu, 3 Sep 2015 22:20:00 -0700 Subject: Input: evdev - do not report errors form flush() commit eb38f3a4f6e86f8bb10a3217ebd85ecc5d763aae upstream. We've got bug reports showing the old systemd-logind (at least system-210) aborting unexpectedly, and this turned out to be because of an invalid error code from close() call to evdev devices. close() is supposed to return only either EINTR or EBADFD, while the device returned ENODEV. logind was overreacting to it and decided to kill itself when an unexpected error code was received. What a tragedy. The bad error code comes from flush fops, and actually evdev_flush() returns ENODEV when device is disconnected or client's access to it is revoked. But in these cases the fact that flush did not actually happen is not an error, but rather normal behavior. For non-disconnected devices result of flush is also not that interesting as there is no potential of data loss and even if it fails application has no way of handling the error. Because of that we are better off always returning success from evdev_flush(). Also returning EINTR from flush()/close() is discouraged (as it is not clear how application should handle this error), so let's stop taking evdev->mutex interruptibly. Bugzilla: http://bugzilla.suse.com/show_bug.cgi?id=939834 Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/input/evdev.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) -- 1.9.1