From: Peter Griffin <peter.griffin@xxxxxxxxxx> [ Upstream commit 409c53f07a81f8db122c461f3255c6f43558c881 ] On Hikey board all lima ip blocks are shared with one irq. This patch avoids a NULL ptr deref crash on this platform on startup. Tested with Weston and kmscube. Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx> Cc: Rob Herring <robh@xxxxxxxxxx> Cc: Daniel Vetter <daniel@xxxxxxxx> Cc: Qiang Yu <yuq825@xxxxxxxxx> Signed-off-by: Qiang Yu <yuq825@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/1555662781-22570-7-git-send-email-peter.griffin@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/lima/lima_pp.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/lima/lima_pp.c b/drivers/gpu/drm/lima/lima_pp.c index d29721e177bf..8fef224b93c8 100644 --- a/drivers/gpu/drm/lima/lima_pp.c +++ b/drivers/gpu/drm/lima/lima_pp.c @@ -64,7 +64,13 @@ static irqreturn_t lima_pp_bcast_irq_handler(int irq, void *data) struct lima_ip *pp_bcast = data; struct lima_device *dev = pp_bcast->dev; struct lima_sched_pipe *pipe = dev->pipe + lima_pipe_pp; - struct drm_lima_m450_pp_frame *frame = pipe->current_task->frame; + struct drm_lima_m450_pp_frame *frame; + + /* for shared irq case */ + if (!pipe->current_task) + return IRQ_NONE; + + frame = pipe->current_task->frame; for (i = 0; i < frame->num_pp; i++) { struct lima_ip *ip = pipe->processor[i]; -- 2.20.1