On Tue, Jan 19, 2021 at 6:47 PM Fabio Estevam <festevam@xxxxxxxxx> wrote: > > Calling the drm_atomic_helper_shutdown() on i.MX5 leads to > the following flow: > > [ 24.557742] [<c0769b78>] (msm_atomic_commit_tail) from [<c06db0b4>] > (commit_tail+0xa4/0x1b0) > [ 24.566349] [<c06db0b4>] (commit_tail) from [<c06dbed0>] > (drm_atomic_helper_commit+0x154/0x188) > [ 24.575193] [<c06dbed0>] (drm_atomic_helper_commit) from > [<c06db604>] (drm_atomic_helper_disable_all+0x154/0x1c0) > [ 24.585599] [<c06db604>] (drm_atomic_helper_disable_all) from > [<c06db704>] (drm_atomic_helper_shutdown+0x94/0x12c) > [ 24.596094] [<c06db704>] (drm_atomic_helper_shutdown) from > > In the i.MX5 case, priv->kms is not populated (as i.MX5 does not use any > of the Qualcomm display controllers), causing a NULL pointer > dereference in msm_atomic_commit_tail(): > > [ 24.268964] 8<--- cut here --- > [ 24.274602] Unable to handle kernel NULL pointer dereference at > virtual address 00000000 > [ 24.283434] pgd = (ptrval) > [ 24.286387] [00000000] *pgd=ca212831 > [ 24.290788] Internal error: Oops: 17 [#1] SMP ARM > [ 24.295609] Modules linked in: > [ 24.298777] CPU: 0 PID: 197 Comm: init Not tainted 5.11.0-rc2-next-20210111 #333 > [ 24.306276] Hardware name: Freescale i.MX53 (Device Tree Support) > [ 24.312442] PC is at msm_atomic_commit_tail+0x54/0xb9c > [ 24.317743] LR is at commit_tail+0xa4/0x1b0 > > Fix the problem by calling drm_atomic_helper_shutdown() conditionally. > > Cc: <stable@xxxxxxxxxxxxxxx> > Fixes: 9d5cbf5fe46e ("drm/msm: add shutdown support for display platform_driver") > Suggested-by: Rob Clark <robdclark@xxxxxxxxx> > Signed-off-by: Fabio Estevam <festevam@xxxxxxxxx> > --- > drivers/gpu/drm/msm/msm_drv.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c > index 108c405e03dd..c082b72b9e3b 100644 > --- a/drivers/gpu/drm/msm/msm_drv.c > +++ b/drivers/gpu/drm/msm/msm_drv.c > @@ -1311,7 +1311,8 @@ static void msm_pdev_shutdown(struct platform_device *pdev) > { > struct drm_device *drm = platform_get_drvdata(pdev); > > - drm_atomic_helper_shutdown(drm); > + if (get_mdp_ver(pdev)) > + drm_atomic_helper_shutdown(drm); Don't we need the same treatment for suspend/resume too? Also if you feel like follow up patch to push this into the helpers with a DRIVER_MODESET check like I described would be kinda neat. -Daniel > } > > static const struct of_device_id dt_match[] = { > -- > 2.25.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel