Hi Li,
On 3/23/26 08:10, Li hongliang wrote:
> From: Srinivasan Shanmugam <[email protected]>
>
> [ Upstream commit cdb637d339572398821204a1142d8d615668f1e9 ]
>
> The issue arises when the array 'adev->vcn.vcn_config' is accessed
> before checking if the index 'adev->vcn.num_vcn_inst' is within the
> bounds of the array.
>
> The fix involves moving the bounds check before the array access. This
> ensures that 'adev->vcn.num_vcn_inst' is within the bounds of the array
> before it is used as an index.
>
> Fixes the below:
> drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1289
> amdgpu_discovery_reg_base_init() error: testing array offset
> 'adev->vcn.num_vcn_inst' after use.
well this patch only fixed a compiler warning and has not much practical value
otherwise.
Why are you sending this for inclusion into the 6.1 kernel?
Regards,
Christian.
>
> Fixes: a0ccc717c4ab ("drm/amdgpu/discovery: validate VCN and SDMA instances")
> Cc: Christian König <[email protected]>
> Cc: Alex Deucher <[email protected]>
> Signed-off-by: Srinivasan Shanmugam <[email protected]>
> Reviewed-by: Alex Deucher <[email protected]>
> Signed-off-by: Alex Deucher <[email protected]>
> [ Minor conflict resolved. ]
> Signed-off-by: Li hongliang <[email protected]>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index 9b1c4d5be61f..a1e006d238cf 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -1128,15 +1128,15 @@ static int amdgpu_discovery_reg_base_init(struct
> amdgpu_device *adev)
> * 0b10 : encode is disabled
> * 0b01 : decode is disabled
> */
> - adev->vcn.vcn_config[adev->vcn.num_vcn_inst] =
> - ip->revision & 0xc0;
> - ip->revision &= ~0xc0;
> - if (adev->vcn.num_vcn_inst <
> AMDGPU_MAX_VCN_INSTANCES)
> + if (adev->vcn.num_vcn_inst <
> AMDGPU_MAX_VCN_INSTANCES) {
> +
> adev->vcn.vcn_config[adev->vcn.num_vcn_inst] =
> + ip->revision & 0xc0;
> adev->vcn.num_vcn_inst++;
> - else
> + } else
> dev_err(adev->dev, "Too many VCN
> instances: %d vs %d\n",
> adev->vcn.num_vcn_inst + 1,
> AMDGPU_MAX_VCN_INSTANCES);
> + ip->revision &= ~0xc0;
> }
> if (le16_to_cpu(ip->hw_id) == SDMA0_HWID ||
> le16_to_cpu(ip->hw_id) == SDMA1_HWID ||
