4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
commit 4f7b0d263833928e947e172eff2d2997179c5cb9 upstream.
It isn't safe to call drm_dev_unregister() without first initializing
mode setting with drm_mode_config_init(). This leads to a crash if
either IO memory can't be remapped or vblank initialization fails.
Fix this by reordering the initialization sequence. Move vblank
initialization after the drm_mode_config_init() call, and move IO
remapping before drm_dev_alloc() to avoid the need to perform clean up
in case of failure.
While at it remove the explicit drm_vblank_cleanup() call from
rcar_du_remove() as the drm_dev_unregister() function already cleans up
vblank.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Signed-off-by: thongsyho <thong.ho.px@xxxxxxxxxxxxxxx>
Signed-off-by: Nhan Nguyen <nhan.nguyen.yb@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/rcar-du/rcar_du_drv.c | 30 +++++++++---------------------
drivers/gpu/drm/rcar-du/rcar_du_kms.c | 7 +++++++
2 files changed, 16 insertions(+), 21 deletions(-)
--- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
@@ -260,7 +260,6 @@ static int rcar_du_remove(struct platfor
drm_kms_helper_poll_fini(ddev);
drm_mode_config_cleanup(ddev);
- drm_vblank_cleanup(ddev);
drm_dev_unref(ddev);
@@ -291,6 +290,15 @@ static int rcar_du_probe(struct platform
rcdu->dev = &pdev->dev;
rcdu->info = of_match_device(rcar_du_of_table, rcdu->dev)->data;
+ platform_set_drvdata(pdev, rcdu);
+
+ /* I/O resources */
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rcdu->mmio = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(rcdu->mmio))
+ ret = PTR_ERR(rcdu->mmio);
+
+ /* DRM/KMS objects */
ddev = drm_dev_alloc(&rcar_du_driver, &pdev->dev);
if (!ddev)
return -ENOMEM;
@@ -300,26 +308,6 @@ static int rcar_du_probe(struct platform
rcdu->ddev = ddev;
ddev->dev_private = rcdu;
- platform_set_drvdata(pdev, rcdu);
-
- /* I/O resources */
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- rcdu->mmio = devm_ioremap_resource(&pdev->dev, mem);
- if (IS_ERR(rcdu->mmio)) {
- ret = PTR_ERR(rcdu->mmio);
- goto error;
- }
-
- /* Initialize vertical blanking interrupts handling. Start with vblank
- * disabled for all CRTCs.
- */
- ret = drm_vblank_init(ddev, (1 << rcdu->info->num_crtcs) - 1);
- if (ret < 0) {
- dev_err(&pdev->dev, "failed to initialize vblank\n");
- goto error;
- }
-
- /* DRM/KMS objects */
ret = rcar_du_modeset_init(rcdu);
if (ret < 0) {
dev_err(&pdev->dev, "failed to initialize DRM/KMS (%d)\n", ret);
--- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
@@ -761,6 +761,13 @@ int rcar_du_modeset_init(struct rcar_du_
if (ret < 0)
return ret;
+ /* Initialize vertical blanking interrupts handling. Start with vblank
+ * disabled for all CRTCs.
+ */
+ ret = drm_vblank_init(dev, (1 << rcdu->info->num_crtcs) - 1);
+ if (ret < 0)
+ return ret;
+
/* Initialize the groups. */
num_groups = DIV_ROUND_UP(rcdu->num_crtcs, 2);