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Date:   Wed, 19 Oct 2022 10:41:18 -0700
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Subject: Re: [PATCH] null_blk: allow teardown on request timeout
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To:     Chaitanya Kulkarni <chaitanyak@nvidia.com>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc:     "axboe@kernel.dk" <axboe@kernel.dk>,
        "damien.lemoal@opensource.wdc.com" <damien.lemoal@opensource.wdc.com>,
        "johannes.thumshirn@wdc.com" <johannes.thumshirn@wdc.com>,
        "ming.lei@redhat.com" <ming.lei@redhat.com>,
        "shinichiro.kawasaki@wdc.com" <shinichiro.kawasaki@wdc.com>,
        "vincent.fu@samsung.com" <vincent.fu@samsung.com>,
        "yukuai3@huawei.com" <yukuai3@huawei.com>
References: <20221016052006.11126-1-kch@nvidia.com>
 <f2baa3b4-81c9-a6d8-0c26-3e695dad5d10@acm.org>
 <d3e05b4e-466b-844c-b815-79233856e527@nvidia.com>
From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <d3e05b4e-466b-844c-b815-79233856e527@nvidia.com>
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On 10/18/22 21:19, Chaitanya Kulkarni wrote:
> Also, I've listed the problem that I've seen first hand for keeping the
> device in the system that is non-responsive due to request timeouts, in
> that case we should let user decide whether user wants to remove or keep
> the device in the system instead of forcing user to keep the device in
> the system bringing down whole system, and these problems are really
> hard to debug even with Teledyne LeCroy [1]. This patch follows the same
> philosophy where user can decide to opt in for removal with module
> parameter. Once opt-in user knows what he is getting into.

Hi Chaitanya,

 From commit f2298c0403b0 ("null_blk: multi queue aware block test 
driver"): "Written to facilitate testing of the blk-mq code". I'm not 
sure of this but adding a mechanism like the one in this patch may fall 
outside the original scope of the null_blk driver.

Thanks,

Bart.