uinput device is always available for writing so we should always report EPOLLOUT and EPOLLWRNORM bits, not only when there is nothing to read from the device. Fixes: d4b675e1b527 ("Input: uinput - fix returning EPOLLOUT from uinput_poll") Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> --- drivers/input/misc/uinput.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c index fd253781be71..0bb456015d8f 100644 --- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -689,13 +689,14 @@ static ssize_t uinput_read(struct file *file, char __user *buffer, static __poll_t uinput_poll(struct file *file, poll_table *wait) { struct uinput_device *udev = file->private_data; + __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */ poll_wait(file, &udev->waitq, wait); if (udev->head != udev->tail) - return EPOLLIN | EPOLLRDNORM; + mask |= EPOLLIN | EPOLLRDNORM; - return EPOLLOUT | EPOLLWRNORM; + return mask; } static int uinput_release(struct inode *inode, struct file *file) -- 2.24.0.393.g34dc348eaf-goog -- Dmitry