Re: [PATCH] lib/test_meminit: add checks for the allocation functions

From: <xkernel.wang@foxmail.com>
To: <akpm@linux-foundation.org>
Cc: <glider@google.com>, <andreyknvl@gmail.com>, <elver@google.com>,
	<dvyukov@google.com>, <ryabinin.a.a@gmail.com>,
	<kasan-dev@googlegroups.com>, <linux-mm@kvack.org>,
	<linux-kernel@vger.kernel.org>, <xkernel.wang@foxmail.com>
Subject: Re: [PATCH] lib/test_meminit: add checks for the allocation functions
Date: Mon, 26 Sep 2022 11:16:37 +0800	[thread overview]
Message-ID: <tencent_F9A4327FE4DE726C503C873F2871FF0F810A@qq.com> (raw)
In-Reply-To: <tencent_D44A49FFB420EDCCBFB9221C8D14DFE12908@qq.com>

Hi Andrew,

This patch seems to have been forgotten.

Regards,
Xiaoke Wang

On Friday, March 4, 2022 5:12 PM, <xkernel.wang@foxmail.com> wrote:
> From: Xiaoke Wang <xkernel.wang@foxmail.com>
> 
> alloc_pages(), kmalloc() and vmalloc() are all memory allocation
> functions which can return NULL when some internal memory failures
> happen. So it is better to check the return of them to catch the failure
> in time for better test them.
> 
> Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
> ---
>  lib/test_meminit.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/lib/test_meminit.c b/lib/test_meminit.c
> index e4f706a..2f4c4bc 100644
> --- a/lib/test_meminit.c
> +++ b/lib/test_meminit.c
> @@ -67,17 +67,24 @@ static int __init do_alloc_pages_order(int order, int
> *total_failures)
>  	size_t size = PAGE_SIZE << order;
> 
>  	page = alloc_pages(GFP_KERNEL, order);
> +	if (!page)
> +		goto err;
>  	buf = page_address(page);
>  	fill_with_garbage(buf, size);
>  	__free_pages(page, order);
> 
>  	page = alloc_pages(GFP_KERNEL, order);
> +	if (!page)
> +		goto err;
>  	buf = page_address(page);
>  	if (count_nonzero_bytes(buf, size))
>  		(*total_failures)++;
>  	fill_with_garbage(buf, size);
>  	__free_pages(page, order);
>  	return 1;
> +err:
> +	(*total_failures)++;
> +	return 1;
>  }
> 
>  /* Test the page allocator by calling alloc_pages with different orders. */
> @@ -100,15 +107,22 @@ static int __init do_kmalloc_size(size_t size, int
> *total_failures)
>  	void *buf;
> 
>  	buf = kmalloc(size, GFP_KERNEL);
> +	if (!buf)
> +		goto err;
>  	fill_with_garbage(buf, size);
>  	kfree(buf);
> 
>  	buf = kmalloc(size, GFP_KERNEL);
> +	if (!buf)
> +		goto err;
>  	if (count_nonzero_bytes(buf, size))
>  		(*total_failures)++;
>  	fill_with_garbage(buf, size);
>  	kfree(buf);
>  	return 1;
> +err:
> +	(*total_failures)++;
> +	return 1;
>  }
> 
>  /* Test vmalloc() with given parameters. */
> @@ -117,15 +131,22 @@ static int __init do_vmalloc_size(size_t size, int
> *total_failures)
>  	void *buf;
> 
>  	buf = vmalloc(size);
> +	if (!buf)
> +		goto err;
>  	fill_with_garbage(buf, size);
>  	vfree(buf);
> 
>  	buf = vmalloc(size);
> +	if (!buf)
> +		goto err;
>  	if (count_nonzero_bytes(buf, size))
>  		(*total_failures)++;
>  	fill_with_garbage(buf, size);
>  	vfree(buf);
>  	return 1;
> +err:
> +	(*total_failures)++;
> +	return 1;
>  }
> 
>  /* Test kmalloc()/vmalloc() by allocating objects of different sizes. */
> --