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Date:   Fri, 18 Feb 2022 08:47:18 +0100
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Subject: Re: [PATCH] drm/amdkfd: Replace one-element array with flexible-array
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To:     cgel.zte@gmail.com, Felix.Kuehling@amd.com
Cc:     alexander.deucher@amd.com, Xinhui.Pan@amd.com, airlied@linux.ie,
        daniel@ffwll.ch, amd-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
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        Zeal Robot <zealci@zte.com.cn>
References: <20220218030943.1905838-1-deng.changcheng@zte.com.cn>
From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
In-Reply-To: <20220218030943.1905838-1-deng.changcheng@zte.com.cn>
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Felix need to comment as well, but I don't think that this will work 
that easily.

By changing the entry from 1 to 0 your are also changing the size of the 
structure.

Regards,
Christian.

Am 18.02.22 um 04:09 schrieb cgel.zte@gmail.com:
> From: Changcheng Deng <deng.changcheng@zte.com.cn>
>
> There is a regular need in the kernel to provide a way to declare having
> a dynamically sized set of trailing elements in a structure. Kernel code
> should always use "flexible array members" for these cases. The older
> style of one-element or zero-length arrays should no longer be used.
> Reference:
> https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
>
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_crat.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.h b/drivers/gpu/drm/amd/amdkfd/kfd_crat.h
> index 482ba84a728d..d7c38fbc533e 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.h
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.h
> @@ -310,7 +310,7 @@ struct cdit_header {
>   	uint32_t	creator_revision;
>   	uint32_t	total_entries;
>   	uint16_t	num_domains;
> -	uint8_t		entry[1];
> +	uint8_t		entry[];
>   };
>   
>   #pragma pack()