On 11/17/25 16:02, Konrad Dybcio wrote:
On 11/17/25 3:51 PM, Neil Armstrong wrote:
On plaforms with an a7xx GPU not supporting IFPC, the ifpc_reglist
if still deferenced in a7xx_patch_pwrup_reglist() which causes
a kernel crash:
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000008
...
pc : a6xx_hw_init+0x155c/0x1e4c [msm]
lr : a6xx_hw_init+0x9a8/0x1e4c [msm]
...
Call trace:
a6xx_hw_init+0x155c/0x1e4c [msm] (P)
msm_gpu_hw_init+0x58/0x88 [msm]
adreno_load_gpu+0x94/0x1fc [msm]
msm_open+0xe4/0xf4 [msm]
drm_file_alloc+0x1a0/0x2e4 [drm]
drm_client_init+0x7c/0x104 [drm]
drm_fbdev_client_setup+0x94/0xcf0 [drm_client_lib]
drm_client_setup+0xb4/0xd8 [drm_client_lib]
msm_drm_kms_post_init+0x2c/0x3c [msm]
msm_drm_init+0x1a4/0x228 [msm]
msm_drm_bind+0x30/0x3c [msm]
...
Check the validity of ifpc_reglist before deferencing the table
to setup the register values.
Fixes: a6a0157cc68e ("drm/msm/a6xx: Enable IFPC on Adreno X1-85")
Signed-off-by: Neil Armstrong <[email protected]>
---
I think it should be fine to skip calling this func altogether
if !ifpc || !pwrup_reglist
Although ifpc && !pwrup_reglist should probably scream very loud
Sorry but why? pwrup_reglist was introduced way earlier than IFPC.
Why would we be skipping the a7xx_patch_pwrup_reglist() because ifpc_reglist is
not declared ???
Neil
Konrad
