On Fri, Aug 04, 2017 at 09:23:28AM +0100, Chris Wilson wrote: > After an event is sent, we try to copy it into the user buffer of the > first waiter in drm_read() and if the user buffer doesn't have enough > room we put it back onto the list. However, we didn't wake up any > subsequent waiter, so that event may sit on the list until either a new > vblank event is sent or a new waiter appears. Rare, but in the worst > case may lead to a stuck process. > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> New subtestcase in igt@drm_read? -Daniel > --- > drivers/gpu/drm/drm_file.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c > index 59b75a974357..7e6db9f7a058 100644 > --- a/drivers/gpu/drm/drm_file.c > +++ b/drivers/gpu/drm/drm_file.c > @@ -524,6 +524,7 @@ ssize_t drm_read(struct file *filp, char __user *buffer, > file_priv->event_space -= length; > list_add(&e->link, &file_priv->event_list); > spin_unlock_irq(&dev->event_lock); > + wake_up_interruptible(&file_priv->event_wait); > break; > } > > -- > 2.13.3 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
