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Subject: Re: [PATCH v6] libata: Add ATA_HORKAGE_NO_NCQ_ON_ATI for Samsung 860
 and 870 SSD.
To:     Hans de Goede <hdegoede@redhat.com>, Kate Hsuan <hpa@redhat.com>,
        Damien Le Moal <damien.lemoal@wdc.com>
Cc:     linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20210903094411.58749-1-hpa@redhat.com>
 <d3488035-d269-2a63-f958-746f371cf490@kernel.dk>
 <f1f0b799-6676-ae06-6a71-05dfeeab8512@redhat.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <cb497516-a2f9-9ebf-a9c6-70aa3ce52940@kernel.dk>
Date:   Fri, 3 Sep 2021 08:05:54 -0600
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On 9/3/21 8:03 AM, Hans de Goede wrote:
> Hi,
> 
> On 9/3/21 2:35 PM, Jens Axboe wrote:
>> On 9/3/21 3:44 AM, Kate Hsuan wrote:
>>> Many users are reporting that the Samsung 860 and 870 SSD are having
>>> various issues when combined with AMD/ATI (vendor ID 0x1002)  SATA
>>> controllers and only completely disabling NCQ helps to avoid these
>>> issues.
>>>
>>> Always disabling NCQ for Samsung 860/870 SSDs regardless of the host
>>> SATA adapter vendor will cause I/O performance degradation with well
>>> behaved adapters. To limit the performance impact to ATI adapters,
>>> introduce the ATA_HORKAGE_NO_NCQ_ON_ATI flag to force disable NCQ
>>> only for these adapters.
>>>
>>> Also, two libata.force parameters (noncqati and ncqati) are introduced
>>> to disable and enable the NCQ for the system which equipped with ATI
>>> SATA adapter and Samsung 860 and 870 SSDs. The user can determine NCQ
>>> function to be enabled or disabled according to the demand.
>>>
>>> After verifying the chipset from the user reports, the issue appears
>>> on AMD/ATI SB7x0/SB8x0/SB9x0 SATA Controllers and does not appear on
>>> recent AMD SATA adapters. The vendor ID of ATI should be 0x1002.
>>> Therefore, ATA_HORKAGE_NO_NCQ_ON_AMD was modified to
>>> ATA_HORKAGE_NO_NCQ_ON_ATI.
>>
>> What's this patch against?
> 
> linux-block/for-next + my pre-cursor patch from here:
> 
> https://lore.kernel.org/linux-ide/20210823095220.30157-1-hdegoede@redhat.com/T/#u

Still had to fixup a hunk, but it was trivial. In any case, I've applied
both now, thanks!

-- 
Jens Axboe