From: Fabio Estevam festevam@gmail.com
commit 6a7e0b0e9fb839caa7c7f25bcf91a95b1c2cbef1 upstream.
Since commit 98659487b845 ("drm/msm: add support to take dpu snapshot") the following NULL pointer dereference is seen on i.MX53:
[ 3.275493] msm msm: bound 30000000.gpu (ops a3xx_ops) [ 3.287174] [drm] Initialized msm 1.8.0 20130625 for msm on minor 0 [ 3.293915] 8<--- cut here --- [ 3.297012] Unable to handle kernel NULL pointer dereference at virtual address 00000028 [ 3.305244] pgd = (ptrval) [ 3.307989] [00000028] *pgd=00000000 [ 3.311624] Internal error: Oops: 805 [#1] SMP ARM [ 3.316430] Modules linked in: [ 3.319503] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.14.0+g682d702b426b #1 [ 3.326652] Hardware name: Freescale i.MX53 (Device Tree Support) [ 3.332754] PC is at __mutex_init+0x14/0x54 [ 3.336969] LR is at msm_disp_snapshot_init+0x24/0xa0
i.MX53 does not use the DPU controller.
Fix the problem by only calling msm_disp_snapshot_init() on platforms that use the DPU controller.
Cc: stable@vger.kernel.org Fixes: 98659487b845 ("drm/msm: add support to take dpu snapshot") Signed-off-by: Fabio Estevam festevam@gmail.com Link: https://lore.kernel.org/r/20210914174831.2044420-1-festevam@gmail.com Signed-off-by: Rob Clark robdclark@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/msm/msm_drv.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -566,10 +566,11 @@ static int msm_drm_init(struct device *d if (ret) goto err_msm_uninit;
- ret = msm_disp_snapshot_init(ddev); - if (ret) - DRM_DEV_ERROR(dev, "msm_disp_snapshot_init failed ret = %d\n", ret); - + if (kms) { + ret = msm_disp_snapshot_init(ddev); + if (ret) + DRM_DEV_ERROR(dev, "msm_disp_snapshot_init failed ret = %d\n", ret); + } drm_mode_config_reset(ddev);
#ifdef CONFIG_DRM_FBDEV_EMULATION