Hi Bin,
Could you please review the below patch that was submitted to address
the automatic modprobe issue.
https://lore.kernel.org/all/[email protected]/
Thanks,
Pratap
On 3/13/2026 7:49 AM, Du, Bin wrote:
Hi Pratap,
FYI, the following patch may resolve the AMD ISP driver not auto-loading
issue (without using MODULE_SOFTDEP). Please double check.
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/
amd/amdgpu/amdgpu_drv.c
index 920595f0d22c..95d26f086d54 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -3212,4 +3212,3 @@ 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 485ecdec9618..409c1ca5a5e1 100644
--- a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
+++ b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
@@ -118,6 +118,29 @@ static int isp_set_performance_state(struct
generic_pm_domain *genpd,
return 0;
}
+/*
+ * MFD core sets the parent GPU's ACPI companion (LNXVIDEO) on each
+ * child, giving them modalias "acpi:LNXVIDEO:" instead of
+ * "platform:<name>". Clear it and retrigger the uevent so udev
+ * sees the correct platform modalias for module autoloading.
+ */
+static int isp_clear_acpi_fwnode(struct device *dev, void *data)
+{
+ struct platform_device *pdev;
+
+ if (!dev->type || !dev->type->name ||
+ strcmp(dev->type->name, "mfd_device"))
+ return 0;
+
+ pdev = to_platform_device(dev);
+ if (pdev->mfd_cell) {
+ device_set_node(dev, NULL);
+ kobject_uevent(&dev->kobj, KOBJ_ADD);
+ }
+
+ return 0;
+}
+
static int isp_genpd_add_device(struct device *dev, void *data)
{
struct generic_pm_domain *gpd = data;
@@ -375,6 +398,13 @@ static int isp_v4_1_1_hw_init(struct amdgpu_isp *isp)
goto failure;
}
+ /*
+ * MFD core sets the parent GPU's ACPI companion (LNXVIDEO) on
+ * each child, giving them modalias "acpi:LNXVIDEO:" instead of
+ * "platform:<name>". Clear it so udev matches by platform alias.
+ */
+ device_for_each_child(isp->parent, NULL, isp_clear_acpi_fwnode);
+
return 0;
failure:
-----Original Message-----
From: Nirujogi, Pratap <[email protected]>
Sent: Wednesday, March 11, 2026 11:29 PM
To: Limonciello, Mario <[email protected]>; Nirujogi, Pratap
<[email protected]>; [email protected]; Deucher,
Alexander <[email protected]>; Limonciello, Mario
<[email protected]>; Koenig, Christian
<[email protected]>
Cc: [email protected]; Chan, Benjamin (Koon Pan)
<[email protected]>; Du, Bin <[email protected]>; Li, King
<[email protected]>
Subject: Re: [PATCH v1] drm/amdgpu: Fix ISP regression issue in kernel
v7.0
On 3/11/2026 1:26 AM, Mario Limonciello wrote:
On 3/10/2026 5:52 PM, Nirujogi, Pratap wrote:
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.
Hi Mario,
Few things to clarify before I split into 2 patches and submit v2.
- Yes, you are correct, the changes in this patch are not directly
related to the Fixes tag 02c057ddefef mentioned. But since it has the
dependency on the below patch for automatic modprobe of isp to work,
I have used the same tag to cover the dependency. My apologies if
this approach is incorrect and misleading.
https://lore.kernel.org/all/[email protected]/
- NULL dereferencing issue with dev->type observed on v7.0 is
specific to this commit 057edc58aa5926d63840c7f30afe0953d3994fa3. As
the wakeup sources are registered using physical device instead of
ACPI device, wakeup source device (wakeup14) is added as the first
child of AMDGPU device; and since its dev->type is not initialized
properly it has resulted in segfault.
Sure this makes sense and is a no brainer to get in. I would just
send this one right now and we can keep noodling on MODULE_SOFTDEP
(more comments below).
thanks, I’ll go ahead and send this one out now and will submit the
MODULE_SOFTDEP change separately after the root cause is identified
( more
details below ).
In 6.19-rc4 or earlier versions, this issue was not observed as the
wakeup source device was never part of AMDGPU children list.
For the changes in isp_v4_1_1.c, I will use Fixes tag 057edc58aa59
in v2.
- MODULE_SOFTDEP change in amdgpu_drv.c is needed for automatic
modprobe of isp (and other amdgpu mfd child devices) to work in v7.0.
But couldn't identify the specific commit in v7.0 that is causing the
issue. I can confirm it is not because of commit 057edc58aa59 as the
automatic modprobe doesn't work even on reverting this commit. Can I
submit this as the fix needed for isp probe to work in v7.0 without
the fixes tag?
MODULE_SOFTDEP is generally for ordering, but I don't think you have
an issue with those modules loading before amdgpu do you? I'm not
really following why the modaliases stopped working and I'm a bit
worried that it's papering over a more nuanced issue still.
yes, this explicit load‑order dependency was not required earlier. I
agree that
the regression point is not clearly identified. I will identify the
bisected commit
and submit the patch later.
To identify the root cause, it might be helpful to do a bisect,
although it's a bit complicated.
1) At any point that has that platform driver conversion you need to
either revert or add the change to auxillary
2) At any point that has 057edc58aa5926d63840c7f30afe0953d3994fa3 you
need to apply the NULL pointer derf fix
3) At any point that has the changes in linux-media for API
adjustments in 7.0 you'll need to pick what version of ISP series to
apply.
I tried #1, #2 and few other combinations, but none of them helped. I
will
investigate further to identify the commit causing the issue.
Thanks,
Pratap
Co-developed-by: Bin Du <[email protected]>
Fixes: 02c057ddefef ("ACPI: video: Convert the driver to a platform
one")
Signed-off-by: Pratap Nirujogi <[email protected]>
---
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;
}
Regards,
Bin
