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Message-ID: <05cfc382-d01d-4370-b8bb-d3805e957f2e@linux.ibm.com>
Date:   Mon, 4 Dec 2023 16:16:31 +0100
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Subject: Re: [PATCH] s390/vfio-ap: handle response code 01 on queue reset
To:     Tony Krowiak <akrowiak@linux.ibm.com>, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc:     jjherne@linux.ibm.com, pasic@linux.ibm.com,
        alex.williamson@redhat.com, kwankhede@nvidia.com,
        frankja@linux.ibm.com, imbrenda@linux.ibm.com, david@redhat.com
References: <20231129143529.260264-1-akrowiak@linux.ibm.com>
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 <1f4720d7-93f1-4e38-a3ad-abaf99596e7c@linux.ibm.com>
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From:   Christian Borntraeger <borntraeger@linux.ibm.com>
In-Reply-To: <1f4720d7-93f1-4e38-a3ad-abaf99596e7c@linux.ibm.com>
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Am 04.12.23 um 15:53 schrieb Tony Krowiak:
> 
> 
> On 11/29/23 12:12, Christian Borntraeger wrote:
>> Am 29.11.23 um 15:35 schrieb Tony Krowiak:
>>> In the current implementation, response code 01 (AP queue number not valid)
>>> is handled as a default case along with other response codes returned from
>>> a queue reset operation that are not handled specifically. Barring a bug,
>>> response code 01 will occur only when a queue has been externally removed
>>> from the host's AP configuration; nn this case, the queue must
>>> be reset by the machine in order to avoid leaking crypto data if/when the
>>> queue is returned to the host's configuration. The response code 01 case
>>> will be handled specifically by logging a WARN message followed by cleaning
>>> up the IRQ resources.
>>>
>>
>> To me it looks like this can be triggered by the LPAR admin, correct? So it
>> is not desireable but possible.
>> In that case I prefer to not use WARN, maybe use dev_warn or dev_err instead.
>> WARN can be a disruptive event if panic_on_warn is set.
> 
> Yes, it can be triggered by the LPAR admin. I can't use dev_warn here because we don't have a reference to any device, but I can use pr_warn if that suffices.

Ok, please use pr_warn then.