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From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
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        bpf@vger.kernel.org, Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: Re: Re: [PATCH] sfc: Check null pointer of rx_queue->page_ring
Date:   Mon, 20 Dec 2021 22:51:34 +0800
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On Mon, Dec 20, 2021 at 10:16:28PM +0800, Greg KH wrote:
> Why not return an error?

Because I have received the mail from Martin Habets that telling me
it doesn't need to return error code.
Here is the mail.
https://lore.kernel.org/lkml/20211219092948.t2iprptmyfrzgthb@gmail.com/
On Sun, Dec 19, 2021 at 05:29:48PM +0800, Martin Habets wrote:
> Your predicate is wrong. The code that uses rx_queue->page_ring
> can deal with it being NULL.
> The only thing you might want to do is set rx_queue->page_ptr_mask
> to 0.

Jiasheng