Re: [PATCH v5 3/3] x86/sgx: Remove redundant if conditions in sgx_encl_create

From: Jarkko Sakkinen
Date: Tue Feb 16 2021 - 03:32:24 EST


On Tue, Feb 16, 2021 at 11:31:33AM +0800, Tianjia Zhang wrote:
> In this scenario, there is no case where va_page is NULL, and
> the error has been checked. The if-condition statement here is
> redundant, so remove the condition detection.
>
> Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
> Acked-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> ---
> arch/x86/kernel/cpu/sgx/ioctl.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
> index 1c6ecf9fbeff..719c21cca569 100644
> --- a/arch/x86/kernel/cpu/sgx/ioctl.c
> +++ b/arch/x86/kernel/cpu/sgx/ioctl.c
> @@ -66,9 +66,10 @@ static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs)
> va_page = sgx_encl_grow(encl);
> if (IS_ERR(va_page))
> return PTR_ERR(va_page);
> - else if (va_page)
> - list_add(&va_page->list, &encl->va_pages);
> - /* else the tail page of the VA page list had free slots. */
> + if (!va_page)
> + return -EIO;

Why this check?

> +
> + list_add(&va_page->list, &encl->va_pages);
>
> /* The extra page goes to SECS. */
> encl_size = secs->size + PAGE_SIZE;
> --
> 2.19.1.3.ge56e4f7
>
>

/Jarkko