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

["Nirujogi, Pratap" <pnirujog@amd.com>]

On 3/11/2026 12:47 PM, Mario Limonciello wrote:
> 
> 
> On 3/11/26 11:19, 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.
>>
>> This regression was introduced in v7.0 as the wakeup sources
>> are registered using physical device instead of ACPI device.
>> This led to adding wakeup source device as the first child of
>> AMDGPU device without initializing dev-type variable, and
>> resulted in segfault when accessed it in the amdgpu isp driver.
>>
>> Fixes: 057edc58aa59 ("ACPI: PM: Register wakeup sources under physical 
>> devices")
>> Co-developed-by: Bin Du <Bin.Du@amd.com>
> 
> Did this pass checkpatch?  In order to use C-d-b this should have Bin's 
> S-o-b I would expect too.  If it was just his original idea for the 
> issue and you implemented it a better tag would be Suggested-by.
> 
I missed the warning checkpatch reported, will fix it in v2. Sure, will 
use Suggested-by tag as well.

Thanks,
Pratap

>> Signed-off-by: Pratap Nirujogi <pratap.nirujogi@amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> 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;
>>       }
>