Re: [PATCH 1/1] scsi_dh_alua: properly handling the ALUA transitioning state

From: Hannes Reinecke <hare@suse.de>
To: Christoph Hellwig <hch@infradead.org>,
	Brian Bunker <brian@purestorage.com>
Cc: linux-scsi@vger.kernel.org
Subject: Re: [PATCH 1/1] scsi_dh_alua: properly handling the ALUA transitioning state
Date: Tue, 24 May 2022 07:33:53 +0200	[thread overview]
Message-ID: <c96e668c-88f9-f883-e580-eb93e6a75595@suse.de> (raw)
In-Reply-To: <YoxsVi0EYuWQxcoO@infradead.org>

On 5/24/22 07:25, Christoph Hellwig wrote:
> On Mon, May 02, 2022 at 08:09:17AM -0700, Brian Bunker wrote:
>>          case SCSI_ACCESS_STATE_ACTIVE:
>>          case SCSI_ACCESS_STATE_LBA:
>> -               return BLK_STS_OK;
>>          case SCSI_ACCESS_STATE_TRANSITIONING:
>> -               return BLK_STS_AGAIN;
>> +               return BLK_STS_OK;
> 
> As there is a lot of discussion on BLK_STS_AGAIN in the thread:
> Independent of the actual outcome here, BLK_STS_AGAIN is fundamentally
> the wrong thing to return here.  BLK_STS_AGAIN must only be returned
> for REQ_NOWAIT requests that would have to block.

Guess we should document that.
It wasn't clear to me that this is a requirement.

Cheers,

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