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Message-ID: <6e656544-ab31-8823-f4aa-3773a47b51d8@kernel.dk>
Date:   Fri, 16 Dec 2022 08:15:18 -0700
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Subject: Re: [PATCH] blk-mq: fix possible NULL pointer access in classic
 polling
To:     huteng19901016@gmail.com
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        "huteng.ht" <huteng.ht@bytedance.com>
References: <20221216150636.18111-1-huteng.ht@bytedance.com>
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From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20221216150636.18111-1-huteng.ht@bytedance.com>
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On 12/16/22 8:06 AM, huteng19901016@gmail.com wrote:
> From: "huteng.ht" <huteng.ht@bytedance.com>
> 
> Since poll method in blk_mq_ops may not be implemented by driver,
> add a judgement to avoid NULL pointer access.

So the queue has QUEUE_FLAG_POLL set, but no -mq_ops->poll() set?
That seems like the real bug.

Where did you see this oops?

-- 
Jens Axboe