Re: [PATCH v1] drm/amdgpu: Fix ISP regression issue in kernel v7.0

[Nirujogi, Pratap]

On 3/9/2026 5:58 PM, Mario Limonciello wrote:

On 3/9/2026 4:50 PM, Pratap Nirujogi wrote:

Add NULL pointer checks for dev->type before accessing
dev->type->name in ISP genpd add/remove functions to
prevent kernel crashes. Also add MODULE_SOFTDEP to ensure
ISP driver dependencies are loaded in correct order.

The regression was introduced in kernel v7.0 where MFD ISP
device enumeration doesn't complete by the time it is added
to gendp. The timing of ISP device enumeration has changed
because of the changes in registering the device sources in
the device hierarchy.

It's a little bit pedantic; but I /think/ there are two different problems here with two different root causes that both happened in 7.0-rc.

As a consequence I think you should have this split out as two separate patches in a series linked to a Fixes tag with the reason for each of them.

sure, will split into 2 patches in the next version.

Co-developed-by: Bin Du <bin...@amd.com>
Fixes: 02c057ddefef ("ACPI: video: Convert the driver to a platform one")
Signed-off-by: Pratap Nirujogi <pratap.niruj...@amd.com>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 +
  drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c | 4 ++--
  2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/ drm/amd/amdgpu/amdgpu_drv.c

index 95d26f086d545..920595f0d22ca 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -3212,3 +3212,4 @@ module_exit(amdgpu_exit);
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_LICENSE("GPL and additional rights");

+MODULE_SOFTDEP("post: amd_isp4_capture i2c-designware-amdisp pinctrl- amdisp");

\ No newline at end of file

diff --git a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c b/drivers/gpu/ drm/amd/amdgpu/isp_v4_1_1.c

index b3590b33cab9e..485ecdec96184 100644
--- a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
+++ b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c

@@ -129,7 +129,7 @@ static int isp_genpd_add_device(struct device *dev, void *data)

      if (!pdev)
          return -EINVAL;
-    if (!dev->type->name) {
+    if (!dev->type || !dev->type->name) {
          drm_dbg(&adev->ddev, "Invalid device type to add\n");
          goto exit;
      }

@@ -165,7 +165,7 @@ static int isp_genpd_remove_device(struct device *dev, void *data)

      if (!pdev)
          return -EINVAL;
-    if (!dev->type->name) {
+    if (!dev->type || !dev->type->name) {
          drm_dbg(&adev->ddev, "Invalid device type to remove\n");
          goto exit;
      }