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Message-ID: <9e91ba36-0a4f-4613-e45c-7919205d8704@grimberg.me>
Date:   Tue, 11 Jul 2023 17:39:51 +0300
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Subject: Re: Fwd: Need NVME QUIRK BOGUS for SAMSUNG MZ1WV480HCGL-000MV
 (Samsung SM-953 Datacenter SSD)
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To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Christoph Hellwig <hch@lst.de>,
        Linux regressions mailing list <regressions@lists.linux.dev>,
        Pankaj Raghav <p.raghav@samsung.com>,
        Keith Busch <kbusch@kernel.org>,
        Bagas Sanjaya <bagasdotme@gmail.com>,
        Jens Axboe <axboe@kernel.dk>,
        "Clemens S." <cspringsguth@gmail.com>,
        Martin Belanger <martin.belanger@dell.com>,
        Chaitanya Kulkarni <kch@nvidia.com>,
        John Meneghini <jmeneghi@redhat.com>,
        Hannes Reinecke <hare@suse.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux NVMe <linux-nvme@lists.infradead.org>,
        Kanchan Joshi <joshi.k@samsung.com>,
        Javier Gonzalez <javier.gonz@samsung.com>,
        =?UTF-8?B?67CV7KeE7ZmY?= <jh.i.park@samsung.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
References: <d18d2a08-9d24-0209-c2cf-baf60bbf5048@gmail.com>
 <ZJsKBkPqoWzYyngS@kbusch-mbp.dhcp.thefacebook.com>
 <6f333133-2cc4-406a-d6c2-642ac6ccabca@leemhuis.info>
 <CGME20230710155902eucas1p2b464a29adc35e983c73b00d18ab5344c@eucas1p2.samsung.com>
 <ZKwqvTMPVmhnkZjS@kbusch-mbp.dhcp.thefacebook.com>
 <f0fdf86e-4293-8e07-835d-b5a866252068@samsung.com>
 <462e0e1e-98ea-0f3c-4aaa-8d44f0a8e664@leemhuis.info>
 <20230711120609.GB27050@lst.de>
 <23017407-83eb-8fb0-5d91-2c7c4ae02544@grimberg.me>
 <2023071135-opt-choosing-51dd@gregkh>
From:   Sagi Grimberg <sagi@grimberg.me>
In-Reply-To: <2023071135-opt-choosing-51dd@gregkh>
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>>>> Well, that "They keep pumping out more and more devices with the same
>>>> breakage" and the "new device" comment from Pankaj below bear the
>>>> question: should we stop trying to play "whack a mole" with all those
>>>> quirk entries and handle devices with duplicate ids just like Windows does?
>>>
>>> As far as I can tell Windows completely ignores the IDs.  Which, looking
>>> back, I'd love to be able to do as well, but they are already used
>>> by udev for the /dev/disk/by-id/ links.   Those are usually not used
>>> on desktop systems, as they use the file system labels and UUIDs, but
>>> that doesn't work for non-file system uses.
>>>
>>> And all this has been working really well with the good old enterprise
>>> SSDs, it's just that the cheap consumer devices keep fucking it up.
>>>
>>> If we'd take it away now we'd break existing users, which puts us between
>>> a rock and a hard place.
>>
>> Maybe the compromise would be to add a modparam that tells the driver
>> to ignore it altogether (like allow_bogus_identifiers) that would
>> default to false. Then people can just workaround the problem instead
>> of having the back-and-fourth with the vendor?
>>
> 
> Module parameters do not work on a per-device basis, sorry.  This isn't
> the 1990's anymore, please do not attempt to add new ones :)

Don't get me wrong, I don't like adding this. But the source of this
is that there are simply too many breakages of non-compliant consumer
drives out there that maybe a compromise would be "globally relax
compliance check in this specific area" as a workaround.

Right now each time this issue is seen in the wild, the only
resolution is either the vendor fixing it, or the driver adds
a quirk, which is positive and exactly what we want. But more
and more users complain, and there is no immediate workaround.