On Wed, Jun 05, 2019 at 09:45:56PM +0200, Daniel Vetter wrote:
> We can be called from any context, we need to be prepared.
>
> Noticed this while hacking on vkms, which calls this function from a
> normal worker. Which really upsets lockdep.
>
> Cc: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx>
> Cc: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx>
> Cc: Emil Velikov <emil.velikov@xxxxxxxxxxxxx>
> Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_debugfs_crc.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c
> index 585169f0dcc5..7f35b5ba1924 100644
> --- a/drivers/gpu/drm/drm_debugfs_crc.c
> +++ b/drivers/gpu/drm/drm_debugfs_crc.c
> @@ -396,8 +396,9 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
> struct drm_crtc_crc *crc = &crtc->crc;
> struct drm_crtc_crc_entry *entry;
> int head, tail;
> + unsigned long flags;
>
> - spin_lock(&crc->lock);
> + spin_lock_irqsave(&crc->lock, flags);
>
> /* Caller may not have noticed yet that userspace has stopped reading */
> if (!crc->entries) {
> @@ -428,7 +429,7 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
> head = (head + 1) & (DRM_CRC_ENTRIES_NR - 1);
> crc->head = head;
>
> - spin_unlock(&crc->lock);
> + spin_unlock_irqrestore(&crc->lock, flags);
>
> wake_up_interruptible(&crc->wq);
>
> --
> 2.20.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@xxxxxxxxxxxxxxxxxxxxx
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Ville Syrjälä
Intel
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
