Re: [PATCH 1/2] media: s5p-mfc: check for firmware allocation before requesting firmware

From: Andrzej Hajda
Date: Thu Nov 02 2017 - 04:13:57 EST


Hi Shuah,

On 06.10.2017 23:30, Shuah Khan wrote:
> Check if firmware is allocated before requesting firmware instead of
> requesting firmware only to release it if firmware is not allocated.
>
> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
> ---
> drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> index 69ef9c2..f064a0d1 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> @@ -55,6 +55,11 @@ int s5p_mfc_load_firmware(struct s5p_mfc_dev *dev)
> * into kernel. */
> mfc_debug_enter();
>
> + if (!dev->fw_buf.virt) {
> + mfc_err("MFC firmware is not allocated\n");
> + return -EINVAL;
> + }
> +
> for (i = MFC_FW_MAX_VERSIONS - 1; i >= 0; i--) {
> if (!dev->variant->fw_name[i])
> continue;
> @@ -75,11 +80,6 @@ int s5p_mfc_load_firmware(struct s5p_mfc_dev *dev)
> release_firmware(fw_blob);
> return -ENOMEM;
> }
> - if (!dev->fw_buf.virt) {
> - mfc_err("MFC firmware is not allocated\n");
> - release_firmware(fw_blob);
> - return -EINVAL;
> - }

Is there any scenario in which dev->fw_buf.virt is null and
s5p_mfc_load_firmware is called?
I suspect this check is not necessary at all.

Regards
Andrzej

> memcpy(dev->fw_buf.virt, fw_blob->data, fw_blob->size);
> wmb();
> release_firmware(fw_blob);