Re: [PATCH][next] habanalabs/gaudi: Fix uninitialized return code rc when read size is zero

[Arnd Bergmann]

On Mon, Apr 12, 2021 at 6:11 PM Colin King <colin.king@xxxxxxxxxxxxx> wrote:
>
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> In the case where size is zero the while loop never assigns rc and the
> return value is uninitialized. Fix this by initializing rc to zero.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: 639781dcab82 ("habanalabs/gaudi: add debugfs to DMA from the device")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
>  drivers/misc/habanalabs/gaudi/gaudi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c b/drivers/misc/habanalabs/gaudi/gaudi.c
> index 8730b691ec61..b751652f80a8 100644
> --- a/drivers/misc/habanalabs/gaudi/gaudi.c
> +++ b/drivers/misc/habanalabs/gaudi/gaudi.c
> @@ -6252,7 +6252,7 @@ static int gaudi_debugfs_read_dma(struct hl_device *hdev, u64 addr, u32 size,
>         dma_addr_t dma_addr;
>         void *kernel_addr;
>         bool is_eng_idle;
> -       int rc, dma_id;
> +       int rc = 0, dma_id;
>
>         kernel_addr = hdev->asic_funcs->asic_dma_alloc_coherent(
>                                                 hdev, SZ_2M,


In general, I don't like adding initializations during the declaration as that
tends to hide warnings for the cases where a later initialization is
missing. In this case it looks correct though.

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>