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Date: Wed, 29 Oct 2025 10:59:07 +0100
From: Christoph Hellwig <hch@lst.de>
To: Daniel Wagner <dwagner@suse.de>
Cc: Christoph Hellwig <hch@lst.de>, Daniel Wagner <wagi@kernel.org>,
	Keith Busch <kbusch@kernel.org>,
	John Meneghini <jmeneghi@redhat.com>,
	Bryan Gurney <bgurney@redhat.com>, linux-nvme@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nvme: drop bogus nid quirk for multipath devices which
 passed id test
Message-ID: <20251029095907.GA1652@lst.de>
References: <20251028-bogus-id-check-v1-1-c087a98b5466@kernel.org> <20251029074403.GA30412@lst.de> <bd91a6c1-cefc-43e2-8dd8-48b7ea241ded@flourine.local>
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On Wed, Oct 29, 2025 at 10:45:57AM +0100, Daniel Wagner wrote:
> On Wed, Oct 29, 2025 at 08:44:03AM +0100, Christoph Hellwig wrote:
> > But more imporantly dropping the quirk for multipath devices is
> > fundamentally the wrong thing to do, as we really need proper IDs for
> > multipathing. So just add another entry for the Dell device using
> > the dell subvendor/subdevice id that does not have the quirk.
> 
> The problem it is not possible to distinguish between the two devices
> based on subvendor/subdevice ids. I've tried to find some way to keep
> those two devices apart, serial numbers but I don't think there is
> something usable. Thus the idea to rely our own sanity checks and
> enable the feature if these pass. 

The problem is that there is no such thing as a sanity check.  Otherwise
life would be easy.  But I really can't believe that Dell is incompetent
enough to not leave a mark of their OEM Firmware version anywhere.