2018-07-27 02:14:07

by Jia-Ju Bai

Subject: [PATCH] input: misc: keyspan_remote: Replace GFP_ATOMIC with GFP_KERNEL in keyspan_probe()

keyspan_probe() is never called in atomic context.
It calls usb_alloc_coherent() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replace with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/input/misc/keyspan_remote.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/misc/keyspan_remote.c b/drivers/input/misc/keyspan_remote.c
index 67482b248b2d..a8937ceac66a 100644
--- a/drivers/input/misc/keyspan_remote.c
+++ b/drivers/input/misc/keyspan_remote.c
@@ -466,7 +466,7 @@ static int keyspan_probe(struct usb_interface *interface, const struct usb_devic
remote->in_endpoint = endpoint;
remote->toggle = -1; /* Set to -1 so we will always not match the toggle from the first remote message. */

- remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_ATOMIC, &remote->in_dma);
+ remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_KERNEL, &remote->in_dma);
if (!remote->in_buffer) {
error = -ENOMEM;
goto fail1;
--
2.17.0

2018-07-27 18:35:08

by Dmitry Torokhov

Subject: Re: [PATCH] input: misc: keyspan_remote: Replace GFP_ATOMIC with GFP_KERNEL in keyspan_probe()

On Fri, Jul 27, 2018 at 10:12:58AM +0800, Jia-Ju Bai wrote:
> keyspan_probe() is never called in atomic context.
> It calls usb_alloc_coherent() with GFP_ATOMIC, which is not necessary.
> GFP_ATOMIC can be replace with GFP_KERNEL.
>
> This is found by a static analysis tool named DCNS written by myself.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>

Applied, thank you.

> ---
> drivers/input/misc/keyspan_remote.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/input/misc/keyspan_remote.c b/drivers/input/misc/keyspan_remote.c
> index 67482b248b2d..a8937ceac66a 100644
> --- a/drivers/input/misc/keyspan_remote.c
> +++ b/drivers/input/misc/keyspan_remote.c
> @@ -466,7 +466,7 @@ static int keyspan_probe(struct usb_interface *interface, const struct usb_devic
> remote->in_endpoint = endpoint;
> remote->toggle = -1; /* Set to -1 so we will always not match the toggle from the first remote message. */
>
> - remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_ATOMIC, &remote->in_dma);
> + remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_KERNEL, &remote->in_dma);
> if (!remote->in_buffer) {
> error = -ENOMEM;
> goto fail1;
> --
> 2.17.0
>

--
Dmitry