[AMD Official Use Only - AMD Internal Distribution Only]
Hi Christian,
-----Original Message-----
From: Christian König <ckoenig.leichtzumerken@xxxxxxxxx>
Sent: Monday, May 13, 2024 7:41 PM
To: Zhang, Jesse(Jie) <Jesse.Zhang@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Koenig, Christian <Christian.Koenig@xxxxxxx>; Huang, Tim <Tim.Huang@xxxxxxx>
Subject: Re: [PATCH 01/22] drm/amdgpu: fix dereference after null check
Am 10.05.24 um 04:50 schrieb Jesse Zhang:
> check the pointer hive before use.
>
> Signed-off-by: Jesse Zhang <Jesse.Zhang@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 77f6fd50002a..00fe3c2d5431 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -5725,7 +5725,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
> * to put adev in the 1st position.
> */
> INIT_LIST_HEAD(&device_list);
> - if (!amdgpu_sriov_vf(adev) && (adev->gmc.xgmi.num_physical_nodes > 1)) {
> + if (!amdgpu_sriov_vf(adev) && (adev->gmc.xgmi.num_physical_nodes >
> +1) && hive) {
That solution looks not optimal to me.
Checking adev->gmc.xgmi.num_physical_nodes > 1 already makes sure that hive shouldn't be NULL.
If automated checkers complain about that we should probably drop the
adev->gmc.xgmi.num_physical_nodes > 1 check and check for hive instead.
[Zhang, Jesse(Jie)]
gmc.xgmi.num_physical_nodes is obtained by reading register GCMC_VM_XGMI_LFB_CNTL.
But getting hive may fail because of no memory (NOMEM),
or the kobject of xgmi hive cannot be initialized in the function amdgpu_get_xgmi_hive.
Is (adev->gmc.xgmi.num_physical_nodes > 1) equivalent to (!hive) here?
Regards
Jesse
Regards,
Christian.
> list_for_each_entry(tmp_adev, &hive->device_list, gmc.xgmi.head) {
> list_add_tail(&tmp_adev->reset_list, &device_list);
> if (adev->shutdown)
