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Date: Fri, 3 May 2024 15:32:41 -0400
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Subject: Re: [PATCH] nvme-pci: Add quirk for broken MSIs
From: Sean Anderson <sean.anderson@linux.dev>
To: Keith Busch <kbusch@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
 Sagi Grimberg <sagi@grimberg.me>, linux-nvme@lists.infradead.org,
 linux-kernel@vger.kernel.org, stable@vger.kernel.org
References: <20240422162822.3539156-1-sean.anderson@linux.dev>
 <ZiaVEfdUXO97eWzV@kbusch-mbp.dhcp.thefacebook.com>
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On 4/22/24 13:15, Sean Anderson wrote:
> On 4/22/24 12:49, Keith Busch wrote:
>> On Mon, Apr 22, 2024 at 12:28:23PM -0400, Sean Anderson wrote:
>>> Sandisk SN530 NVMe drives have broken MSIs. On systems without MSI-X
>>> support, all commands time out resulting in the following message:
>>> 
>>> nvme nvme0: I/O tag 12 (100c) QID 0 timeout, completion polled
>>> 
>>> These timeouts cause the boot to take an excessively-long time (over 20
>>> minutes) while the initial command queue is flushed.
>>> 
>>> Address this by adding a quirk for drives with buggy MSIs. The lspci
>>> output for this device (recorded on a system with MSI-X support) is:
>> 
>> Based on your description, the patch looks good. This will fallback to
>> legacy emulated pin interrupts, and that's better than timeout polling,
>> but will still appear sluggish compared to MSI's. Is there an errata
>> from the vendor on this? I'm just curious if the bug is at the Device ID
>> level, and not something we could constrain to a particular model or
>> firmware revision. 
> 
> I wasn't able to find any errata for this drive. I wasn't able to
> determine if there are any firmware updates for this drive (FWIW I have
> version "21160001"). I'll contact WD and see if they know about this
> issue.

Well, the response from WD support was "we don't support Linux, and if
we did there aren't any bugs in the drive anyway".

--Sean