From 471bf2406c043491b1a8288e5f04bc278f7d7ca1 Mon Sep 17 00:00:00 2001 From: Michael Tretter Date: Fri, 28 Oct 2022 11:52:05 +0200 Subject: drm/rockchip: vop2: fix null pointer in plane_atomic_disable If the vop2_plane_atomic_disable function is called with NULL as a state, accessing the old_pstate runs into a null pointer exception. However, the drm_atomic_helper_disable_planes_on_crtc function calls the atomic_disable callback with state NULL. Allow to disable a plane without passing a plane state by checking the old_pstate only if a state is passed. Signed-off-by: Michael Tretter Signed-off-by: Heiko Stuebner Link: https://patchwork.freedesktop.org/patch/msgid/20221028095206.2136601-2-m.tretter@pengutronix.de --- drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/gpu/drm/rockchip/rockchip_drm_vop2.c') diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index aac20be5ac08..26f8a8489ded 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c @@ -996,13 +996,15 @@ static int vop2_plane_atomic_check(struct drm_plane *plane, static void vop2_plane_atomic_disable(struct drm_plane *plane, struct drm_atomic_state *state) { - struct drm_plane_state *old_pstate = drm_atomic_get_old_plane_state(state, plane); + struct drm_plane_state *old_pstate = NULL; struct vop2_win *win = to_vop2_win(plane); struct vop2 *vop2 = win->vop2; drm_dbg(vop2->drm, "%s disable\n", win->data->name); - if (!old_pstate->crtc) + if (state) + old_pstate = drm_atomic_get_old_plane_state(state, plane); + if (old_pstate && !old_pstate->crtc) return; vop2_win_disable(win); -- cgit From 447fb14bf07905b880c9ed1ea92c53d6dd0649d7 Mon Sep 17 00:00:00 2001 From: Michael Tretter Date: Fri, 28 Oct 2022 11:52:06 +0200 Subject: drm/rockchip: vop2: disable planes when disabling the crtc The vop2 driver needs to explicitly disable the planes if the crtc is disabled. Unless the planes are explicitly disabled, the address of the last framebuffer is kept in the registers of the VOP2. When re-enabling the encoder after it has been disabled by the driver, the VOP2 will start and read the framebuffer that has been freed but is still pointed to by the register. The iommu will catch these read accesses and print errors. Explicitly disable the planes when the crtc is disabled to reset the registers. Signed-off-by: Michael Tretter Signed-off-by: Heiko Stuebner Link: https://patchwork.freedesktop.org/patch/msgid/20221028095206.2136601-3-m.tretter@pengutronix.de --- drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/gpu/drm/rockchip/rockchip_drm_vop2.c') diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index 26f8a8489ded..105a548d0abe 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c @@ -877,10 +877,14 @@ static void vop2_crtc_atomic_disable(struct drm_crtc *crtc, { struct vop2_video_port *vp = to_vop2_video_port(crtc); struct vop2 *vop2 = vp->vop2; + struct drm_crtc_state *old_crtc_state; int ret; vop2_lock(vop2); + old_crtc_state = drm_atomic_get_old_crtc_state(state, crtc); + drm_atomic_helper_disable_planes_on_crtc(old_crtc_state, false); + drm_crtc_vblank_off(crtc); /* -- cgit