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Subject: Re: [PATCH v2] nvme-multipath: Early exit if no path is available
To:     Chao Leng <lengchao@huawei.com>, Sagi Grimberg <sagi@grimberg.me>,
        Daniel Wagner <dwagner@suse.de>
Cc:     linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        Jens Axboe <axboe@fb.com>, Keith Busch <kbusch@kernel.org>,
        Christoph Hellwig <hch@lst.de>
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From:   Hannes Reinecke <hare@suse.de>
Message-ID: <47a1b796-9d91-5947-4bac-dd8f397041a3@suse.de>
Date:   Mon, 1 Feb 2021 09:57:22 +0100
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On 2/1/21 9:47 AM, Chao Leng wrote:
> 
> 
> On 2021/2/1 15:29, Hannes Reinecke wrote:[ .. ]
>> Urgh. Please, no. That is well impossible to debug.
>> Can you please open-code it to demonstrate where the difference to the 
>> current (and my fixed) versions is?
>> I'm still not clear where the problem is once we applied both patches.
> For example assume the list has three path, and all path is not 
> NVME_ANA_OPTIMIZED:
> head->next = ns1;
> ns1->next = ns2;
> ns2->next = head;
> old->next = ns2;
> 
And this is where I have issues with.
Where does 'old' come from?
Clearly it was part of the list at one point; so what happened to it?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
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