2018-07-27 02:30:28

by Jia-Ju Bai

Subject: [PATCH] input: tablet: aiptek: Replace GFP_ATOMIC with GFP_KERNEL in aiptek_probe()

aiptek_probe() is never called in atomic context.
It calls usb_alloc_coherent() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced 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/tablet/aiptek.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/tablet/aiptek.c b/drivers/input/tablet/aiptek.c
index 545fa6e89035..c82cd5079d0e 100644
--- a/drivers/input/tablet/aiptek.c
+++ b/drivers/input/tablet/aiptek.c
@@ -1712,7 +1712,7 @@ aiptek_probe(struct usb_interface *intf, const struct usb_device_id *id)
}

aiptek->data = usb_alloc_coherent(usbdev, AIPTEK_PACKET_LENGTH,
- GFP_ATOMIC, &aiptek->data_dma);
+ GFP_KERNEL, &aiptek->data_dma);
if (!aiptek->data) {
dev_warn(&intf->dev, "cannot allocate usb buffer\n");
goto fail1;
--
2.17.0

2018-07-27 18:36:43

by Dmitry Torokhov

Subject: Re: [PATCH] input: tablet: aiptek: Replace GFP_ATOMIC with GFP_KERNEL in aiptek_probe()

On Fri, Jul 27, 2018 at 10:29:20AM +0800, Jia-Ju Bai wrote:
> aiptek_probe() is never called in atomic context.
> It calls usb_alloc_coherent() with GFP_ATOMIC, which is not necessary.
> GFP_ATOMIC can be replaced 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/tablet/aiptek.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/input/tablet/aiptek.c b/drivers/input/tablet/aiptek.c
> index 545fa6e89035..c82cd5079d0e 100644
> --- a/drivers/input/tablet/aiptek.c
> +++ b/drivers/input/tablet/aiptek.c
> @@ -1712,7 +1712,7 @@ aiptek_probe(struct usb_interface *intf, const struct usb_device_id *id)
> }
>
> aiptek->data = usb_alloc_coherent(usbdev, AIPTEK_PACKET_LENGTH,
> - GFP_ATOMIC, &aiptek->data_dma);
> + GFP_KERNEL, &aiptek->data_dma);
> if (!aiptek->data) {
> dev_warn(&intf->dev, "cannot allocate usb buffer\n");
> goto fail1;
> --
> 2.17.0
>

--
Dmitry