Re: [PATCH] firmware: meson_sm: Fix memcpy vs iomem type warnings

[Neil Armstrong]

On 12/10/2022 20:53, Kees Cook wrote:
> Use memcpy_{toio,fromio}() instead of memcpy(). Silences warnings from
> Sparse:
>
> drivers/firmware/meson/meson_sm.c:170:17: warning: incorrect type in argument 1 (different address spaces)
> drivers/firmware/meson/meson_sm.c:170:17:    expected void const *
> drivers/firmware/meson/meson_sm.c:170:17:    got void [noderef] __iomem *sm_shmem_out_base
> drivers/firmware/meson/meson_sm.c:170:17: warning: incorrect type in argument 2 (different address spaces)
> drivers/firmware/meson/meson_sm.c:170:17:    expected void const *
> drivers/firmware/meson/meson_sm.c:170:17:    got void [noderef] __iomem *sm_shmem_out_base
> drivers/firmware/meson/meson_sm.c:206:9: warning: incorrect type in argument 1 (different address spaces)
> drivers/firmware/meson/meson_sm.c:206:9:    expected void const *
> drivers/firmware/meson/meson_sm.c:206:9:    got void [noderef] __iomem *sm_shmem_in_base
> drivers/firmware/meson/meson_sm.c:206:9: warning: incorrect type in argument 1 (different address spaces)
> drivers/firmware/meson/meson_sm.c:206:9:    expected void const *
> drivers/firmware/meson/meson_sm.c:206:9:    got void [noderef] __iomem *sm_shmem_in_base
> drivers/firmware/meson/meson_sm.c:206:9: warning: incorrect type in argument 1 (different address spaces)
> drivers/firmware/meson/meson_sm.c:206:9:    expected void const *
> drivers/firmware/meson/meson_sm.c:206:9:    got void [noderef] __iomem *sm_shmem_in_base
> drivers/firmware/meson/meson_sm.c:206:9: warning: incorrect type in argument 1 (different address spaces)
> drivers/firmware/meson/meson_sm.c:206:9:    expected void *
> drivers/firmware/meson/meson_sm.c:206:9:    got void [noderef] __iomem *sm_shmem_in_base
>
> While here, fix this warning as well:
>
> drivers/firmware/meson/meson_sm.c:85:24: warning: Using plain integer as NULL pointer
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Link: https://lore.kernel.org/lkml/202210122023.zF56nCzM-lkp@xxxxxxxxx
> Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> Cc: Kevin Hilman <khilman@xxxxxxxxxxxx>
> Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> Cc: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-amlogic@xxxxxxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
>   drivers/firmware/meson/meson_sm.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
> index 77aa5c6398aa..4efde225a580 100644
> --- a/drivers/firmware/meson/meson_sm.c
> +++ b/drivers/firmware/meson/meson_sm.c
> @@ -82,7 +82,7 @@ static void __iomem *meson_sm_map_shmem(u32 cmd_shmem, unsigned int size)
>   
>   	sm_phy_base = __meson_sm_call(cmd_shmem, 0, 0, 0, 0, 0);
>   	if (!sm_phy_base)
> -		return 0;
> +		return NULL;
>   
>   	return ioremap_cache(sm_phy_base, size);
>   }
> @@ -167,7 +167,7 @@ int meson_sm_call_read(struct meson_sm_firmware *fw, void *buffer,
>   		size = bsize;
>   
>   	if (buffer)
> -		memcpy(buffer, fw->sm_shmem_out_base, size);
> +		memcpy_fromio(buffer, fw->sm_shmem_out_base, size);
>   
>   	return ret;
>   }
> @@ -203,7 +203,7 @@ int meson_sm_call_write(struct meson_sm_firmware *fw, void *buffer,
>   	if (!fw->chip->cmd_shmem_in_base)
>   		return -EINVAL;
>   
> -	memcpy(fw->sm_shmem_in_base, buffer, size);
> +	memcpy_toio(fw->sm_shmem_in_base, buffer, size);
>   
>   	if (meson_sm_call(fw, cmd_index, &written, arg0, arg1, arg2, arg3, arg4) < 0)
>   		return -EINVAL;

Thanks,

Acked-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>