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Subject: Re: [PATCH 2/3] scsi: fnic: Stop setting scsi_cmnd.tag
To:     Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>,
        "Bart Van Assche" <bvanassche@acm.org>
CC:     <satishkh@cisco.com>, <sebaddel@cisco.com>, <kartilak@cisco.com>,
        <jejb@linux.ibm.com>, <martin.petersen@oracle.com>,
        <linux-scsi@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <1628862553-179450-1-git-send-email-john.garry@huawei.com>
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 <20210814073948.GA21536@lst.de>
 <b6216e3f-5339-18e4-ca31-61c7968efbb1@suse.de>
From:   John Garry <john.garry@huawei.com>
Message-ID: <2e6dd74f-bd5a-22b8-f20b-d4b54fc4ade3@huawei.com>
Date:   Mon, 16 Aug 2021 11:00:29 +0100
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On 14/08/2021 13:35, Hannes Reinecke wrote:
> On 8/14/21 9:39 AM, Christoph Hellwig wrote:
>> On Fri, Aug 13, 2021 at 08:17:45PM -0700, Bart Van Assche wrote:
>>> On 8/13/21 6:49 AM, John Garry wrote:
>>>> It is never read. Setting it and the request tag seems dodgy
>>>> anyway.
>>>
>>> This is done because there is code in the SCSI error handler that may
>>> allocate a SCSI command without allocating a tag. See also
>>> scsi_ioctl_reset().

Right, so we just get a loan of the tag of a real request. fnic driver 
comment:

"Really should fix the midlayer to pass in a proper request for ioctls..."

>>
>> Yes.  Hannes had a great series to stop passing the pointless scsi_cmnd
>> to the reset methods.  Hannes, any chance you coul look into
>> resurrecting that?
>>
> Sure.

The latest iteration of that series - at v7 - still passed that fake 
SCSI command to the reset method, and the reset method allocated the 
internal command.

So will we change change scsi_ioctl_reset() to allocate an internal 
command, rather than the LLDD?

Thanks,
John