Re: [PATCH v1] drm/rockchip: fix fbdev crash when not use DRM_FBDEV_EMULATION

On Thu, Aug 04, 2016 at 10:21:58AM +0800, Mark Yao wrote:

[ 1.162571] Unable to handle kernel NULL pointer dereference at virtual address 00000200 [ 1.165656] Modules linked in: [ 1.165941] CPU: 5 PID: 143 Comm: kworker/5:2 Not tainted 4.4.15 #237 [ 1.166506] Hardware name: Rockchip RK3399 Evaluation Board v1 (Android) (DT) [ 1.167153] Workqueue: events output_poll_execute [ 1.168231] PC is at mutex_lock+0x14/0x44 [ 1.168586] LR is at drm_fb_helper_hotplug_event+0x28/0xcc [ 1.172192] [<ffffff8008982110>] mutex_lock+0x14/0x44 [ 1.172196] [<ffffff80084025a4>] drm_fb_helper_hotplug_event+0x28/0xcc [ 1.172201] [<ffffff8008427ae4>] rockchip_drm_output_poll_changed+0x14/0x1c [ 1.172204] [<ffffff80083f7c4c>] drm_kms_helper_hotplug_event+0x28/0x34 [ 1.172207] [<ffffff80083f7ddc>] output_poll_execute+0x150/0x198 [ 1.172212] [<ffffff80080b0ea8>] process_one_work+0x218/0x3dc [ 1.172215] [<ffffff80080b1578>] worker_thread+0x24c/0x374 [ 1.172217] [<ffffff80080b5bcc>] kthread+0xdc/0xe4 [ 1.172222] [<ffffff8008084cd0>] ret_from_fork+0x10/0x40

Signed-off-by: Mark Yao mark.yao@rock-chips.com

Change in v1: Advised by Daniel Vetter only do the struct->pointer conversion alone

Yeah, that looks much more in line with how the optional fbdev support is supposed to be used. -Daniel

drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 6 +++--- drivers/gpu/drm/rockchip/rockchip_drm_drv.h | 2 +- drivers/gpu/drm/rockchip/rockchip_drm_fb.c | 2 +- drivers/gpu/drm/rockchip/rockchip_drm_fbdev.c | 17 ++++++++++------- 4 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c index a822d49..fe22f76 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c @@ -261,7 +261,7 @@ static void rockchip_drm_lastclose(struct drm_device *dev) { struct rockchip_drm_private *priv = dev->dev_private;

• drm_fb_helper_restore_fbdev_mode_unlocked(&priv->fbdev_helper);

• drm_fb_helper_restore_fbdev_mode_unlocked(priv->fbdev_helper);

}

static const struct file_operations rockchip_drm_driver_fops = { @@ -311,7 +311,7 @@ void rockchip_drm_fb_suspend(struct drm_device *drm) struct rockchip_drm_private *priv = drm->dev_private;

console_lock();

• drm_fb_helper_set_suspend(&priv->fbdev_helper, 1);

• drm_fb_helper_set_suspend(priv->fbdev_helper, 1); console_unlock();

}

@@ -320,7 +320,7 @@ void rockchip_drm_fb_resume(struct drm_device *drm) struct rockchip_drm_private *priv = drm->dev_private;

console_lock();

• drm_fb_helper_set_suspend(&priv->fbdev_helper, 0);

• drm_fb_helper_set_suspend(priv->fbdev_helper, 0); console_unlock();

}

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h index ea39329..f005f3f 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h @@ -57,7 +57,7 @@ struct rockchip_crtc_state {

• @num_pipe: number of pipes for this device.

*/ struct rockchip_drm_private {

• struct drm_fb_helper fbdev_helper;

• struct drm_fb_helper *fbdev_helper; struct drm_gem_object *fbdev_bo; const struct rockchip_crtc_funcs *crtc_funcs[ROCKCHIP_MAX_CRTC]; struct drm_atomic_state *state;

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c index 55c5273..dc034ec 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c @@ -156,7 +156,7 @@ err_gem_object_unreference: static void rockchip_drm_output_poll_changed(struct drm_device *dev) { struct rockchip_drm_private *private = dev->dev_private;

• struct drm_fb_helper *fb_helper = &private->fbdev_helper;

• struct drm_fb_helper *fb_helper = private->fbdev_helper;

  if (fb_helper) drm_fb_helper_hotplug_event(fb_helper);

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fbdev.c b/drivers/gpu/drm/rockchip/rockchip_drm_fbdev.c index 207e01d..6b50dfa 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_fbdev.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_fbdev.c @@ -22,14 +22,12 @@ #include "rockchip_drm_fb.h"

#define PREFERRED_BPP 32 -#define to_drm_private(x) \

• container_of(x, struct rockchip_drm_private, fbdev_helper)
  
  

static int rockchip_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma) { struct drm_fb_helper *helper = info->par;

• struct rockchip_drm_private *private = to_drm_private(helper);

• struct rockchip_drm_private *private = helper->dev->dev_private;

  return rockchip_gem_mmap_buf(private->fbdev_bo, vma);

} @@ -50,7 +48,7 @@ static struct fb_ops rockchip_drm_fbdev_ops = { static int rockchip_drm_fbdev_create(struct drm_fb_helper *helper, struct drm_fb_helper_surface_size *sizes) {

• struct rockchip_drm_private *private = to_drm_private(helper);

• struct rockchip_drm_private *private = helper->dev->dev_private; struct drm_mode_fb_cmd2 mode_cmd = { 0 }; struct drm_device *dev = helper->dev; struct rockchip_gem_object *rk_obj;

@@ -139,7 +137,11 @@ int rockchip_drm_fbdev_init(struct drm_device *dev)

num_crtc = dev->mode_config.num_crtc;

• helper = &private->fbdev_helper;

• helper = devm_kzalloc(dev->dev, sizeof(*helper), GFP_KERNEL);

• if (!helper)

• return -ENOMEM;
  

• private->fbdev_helper = helper;

  drm_fb_helper_prepare(dev, helper, &rockchip_drm_fb_helper_funcs);

@@ -173,9 +175,10 @@ err_drm_fb_helper_fini: void rockchip_drm_fbdev_fini(struct drm_device *dev) { struct rockchip_drm_private *private = dev->dev_private;

• struct drm_fb_helper *helper;

• struct drm_fb_helper *helper = private->fbdev_helper;

• helper = &private->fbdev_helper;

• if (!helper)

• return;
  
  

  drm_fb_helper_unregister_fbi(helper); drm_fb_helper_release_fbi(helper);

-- 1.9.1

---

dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel