2023-01-07 19:05:12

by Tom Rix

Subject: [PATCH] habanalabs: remove redundant memset

From reviewing the code, the line
memset(kdata, 0, usize);
is not needed because kdata is either zeroed by
kdata = kzalloc(asize, GFP_KERNEL);
when allocated at runtime or by
char stack_kdata[128] = {0};
at compile time.

Signed-off-by: Tom Rix <[email protected]>
---
drivers/accel/habanalabs/common/habanalabs_ioctl.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/accel/habanalabs/common/habanalabs_ioctl.c b/drivers/accel/habanalabs/common/habanalabs_ioctl.c
index 619d56c40b30..949d38527160 100644
--- a/drivers/accel/habanalabs/common/habanalabs_ioctl.c
+++ b/drivers/accel/habanalabs/common/habanalabs_ioctl.c
@@ -1123,8 +1123,6 @@ static long _hl_ioctl(struct file *filep, unsigned int cmd, unsigned long arg,
retcode = -EFAULT;
goto out_err;
}
- } else if (cmd & IOC_OUT) {
- memset(kdata, 0, usize);
}

retcode = func(hpriv, kdata);
--
2.27.0

2023-01-08 14:54:29

by Oded Gabbay

Subject: Re: [PATCH] habanalabs: remove redundant memset

On Sat, Jan 7, 2023 at 8:48 PM Tom Rix <[email protected]> wrote:
>
> From reviewing the code, the line
> memset(kdata, 0, usize);
> is not needed because kdata is either zeroed by
> kdata = kzalloc(asize, GFP_KERNEL);
> when allocated at runtime or by
> char stack_kdata[128] = {0};
> at compile time.
>
> Signed-off-by: Tom Rix <[email protected]>
> ---
> drivers/accel/habanalabs/common/habanalabs_ioctl.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/accel/habanalabs/common/habanalabs_ioctl.c b/drivers/accel/habanalabs/common/habanalabs_ioctl.c
> index 619d56c40b30..949d38527160 100644
> --- a/drivers/accel/habanalabs/common/habanalabs_ioctl.c
> +++ b/drivers/accel/habanalabs/common/habanalabs_ioctl.c
> @@ -1123,8 +1123,6 @@ static long _hl_ioctl(struct file *filep, unsigned int cmd, unsigned long arg,
> retcode = -EFAULT;
> goto out_err;
> }
> - } else if (cmd & IOC_OUT) {
> - memset(kdata, 0, usize);
> }
>
> retcode = func(hpriv, kdata);
> --
> 2.27.0
>

Reviewed-by: Oded Gabbay <[email protected]>
Applied to -next.

Thanks,
Oded