Re: [PATCH] hid: intel-ish-hid: avoid bogus uninitialized-variable warning

[Srinivas Pandruvada]

On Tue, 2020-04-28 at 23:53 +0200, Arnd Bergmann wrote:
> Older compilers like gcc-4.8 don't see that the variable is
> initialized when it is used:
> 
> In file included from include/linux/compiler_types.h:68:0,
>                  from <command-line>:0:
> drivers/hid/intel-ish-hid/ishtp-fw-loader.c: In function
> 'load_fw_from_host':
> include/linux/compiler-gcc.h:75:45: warning:
> 'fw_info.ldr_capability.max_dma_buf_size' may be used uninitialized
> in this function [-Wmaybe-uninitialized]
>  #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix),
> __COUNTER__)
>                                              ^
> drivers/hid/intel-ish-hid/ishtp-fw-loader.c:770:22: note:
> 'fw_info.ldr_capability.max_dma_buf_size' was declared here
>   struct shim_fw_info fw_info;
>                       ^
> 
> Make sure to initialize it before returning an error from
> ish_query_loader_prop().
> 
> Fixes: 91b228107da3 ("HID: intel-ish-hid: ISH firmware loader client
> driver")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>


> ---
>  drivers/hid/intel-ish-hid/ishtp-fw-loader.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> index aa2dbed30fc3..6cf59fd26ad7 100644
> --- a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> +++ b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> @@ -480,6 +480,7 @@ static int ish_query_loader_prop(struct
> ishtp_cl_data *client_data,
>  			    sizeof(ldr_xfer_query_resp));
>  	if (rv < 0) {
>  		client_data->flag_retry = true;
> +		*fw_info = (struct shim_fw_info){};
>  		return rv;
>  	}
>  
> @@ -489,6 +490,7 @@ static int ish_query_loader_prop(struct
> ishtp_cl_data *client_data,
>  			"data size %d is not equal to size of
> loader_xfer_query_response %zu\n",
>  			rv, sizeof(struct loader_xfer_query_response));
>  		client_data->flag_retry = true;
> +		*fw_info = (struct shim_fw_info){};
>  		return -EMSGSIZE;
>  	}
>