[PATCH v2] drm/amd/amdgpu: Fix an uninitialized variable

[Alex Deucher]

On Mon, Jan 9, 2023 at 10:58 AM Srinivasan Shanmugam
<srinivasan.shanmugam at amd.com> wrote:
>
>   CC      drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.o
> drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c:217:71: error: variable 'i' is uninitialized when used here [-Werror,-Wuninitialized]
>                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s%d.bin", ucode_prefix, i);
>                                                                                     ^
> drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c:207:16: note: initialize the variable 'i' to silence this warning
>         int err = 0, i;
>                       ^
>                        = 0
>
> As suggested by Christian, buggy
> "snprintf(fw_name, sizeof(fw_name), "amdgpu/%s%d.bin", ucode_prefix, i);"
> shouldn't be "i" in the first place, but rather using "instance",
> because for instance greater than 0, we want to have different
> sdma firmware for different instance we add the instance number.
>
> Remove setting err to 0 as well. This is considered very bad coding style.
>
> Cc: Christian König <christian.koenig at amd.com>
> Cc: Mario Limonciello <mario.limonciello at amd.com>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam at amd.com>

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

> Change-Id: I2f1180af4f37bf1efd4d47e7bf64425b0b3809fb
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
> index 0e1e2521fe25a..e9b78739b9ff7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
> @@ -204,7 +204,7 @@ int amdgpu_sdma_init_microcode(struct amdgpu_device *adev,
>  {
>         struct amdgpu_firmware_info *info = NULL;
>         const struct common_firmware_header *header = NULL;
> -       int err = 0, i;
> +       int err, i;
>         const struct sdma_firmware_header_v2_0 *sdma_hdr;
>         uint16_t version_major;
>         char ucode_prefix[30];
> @@ -214,7 +214,7 @@ int amdgpu_sdma_init_microcode(struct amdgpu_device *adev,
>         if (instance == 0)
>                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s.bin", ucode_prefix);
>         else
> -               snprintf(fw_name, sizeof(fw_name), "amdgpu/%s%d.bin", ucode_prefix, i);
> +               snprintf(fw_name, sizeof(fw_name), "amdgpu/%s%d.bin", ucode_prefix, instance);
>         err = amdgpu_ucode_request(adev, &adev->sdma.instance[instance].fw, fw_name);
>         if (err)
>                 goto out;
> --
> 2.25.1
>