[PATCH v1] drm/rockchip: fix fbdev crash when not use DRM_FBDEV_EMULATION
From: Mark Yao
Date: Wed Aug 03 2016 - 22:22:45 EST
[ 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@xxxxxxxxxxxxxx>
---
Change in v1:
Advised by Daniel Vetter
only do the struct->pointer conversion alone
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