On 2015년 02월 18일 02:14, Charles Keepax wrote: > The commit "drm/exynos: remove exynos_plane_dpms" (d9ea6256) removed the > use of the enabled flag, which means that the code may attempt to call > win_enable on a NULL crtc. This results in the following oops on Hmm... it's strange. plane->funcs->destroy() is called prior to crtc->funcs->destroy() so it should be exynos_crtc is not NULL. However, it seems there is any corner case we didn't catch up. Applied. Thanks, Inki Dae > Arndale: > > [ 1.673479] Unable to handle kernel NULL pointer dereference at virtual address 00000368 > [ 1.681500] pgd = c0004000 > [ 1.684154] [00000368] *pgd=00000000 > [ 1.687713] Internal error: Oops: 5 [#1] PREEMPT SMP ARM > [ 1.693012] Modules linked in: > [ 1.696045] CPU: 1 PID: 1 Comm: swapper/0 Not tainted > 3.19.0-07545-g57485fa #1907 > [ 1.703524] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) > (....) > [ 2.014803] [<c02f9cfc>] (exynos_plane_destroy) from [<c02e61b4>] (drm_mode_config_cleanup+0x168/0x20c) > [ 2.024178] [<c02e61b4>] (drm_mode_config_cleanup) from [<c02f66fc>] (exynos_drm_load+0xac/0x12c) > > This patch adds in a check to ensure exynos_crtc is not NULL before it > is dereferenced. > > Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/exynos/exynos_drm_plane.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c > index 2dfb847..78fc0a1 100644 > --- a/drivers/gpu/drm/exynos/exynos_drm_plane.c > +++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c > @@ -176,7 +176,7 @@ static int exynos_disable_plane(struct drm_plane *plane) > struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane); > struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(plane->crtc); > > - if (exynos_crtc->ops->win_disable) > + if (exynos_crtc && exynos_crtc->ops->win_disable) > exynos_crtc->ops->win_disable(exynos_crtc, > exynos_plane->zpos); > > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
