Re: [PATCH] nvme: Add 48-bit DMA address quirk

[Filippo Sironi]

On 2/3/21 10:51 AM, Christoph Hellwig wrote:
> On Wed, Feb 03, 2021 at 10:43:38AM +0100, Filippo Sironi wrote:
> > Certain NVMe controllers don't support 64-bit DMA addresses.  Instead,
> > they are limited to 48-bit DMA addresses.  Let's add a quirk to use them
> > properly.
>
> WTF?  This is such a grave NVMe spec compiance bug that I do not think
> we should support this buggy mess in Linux.

I don't disagree on the first part of your sentence, this is a big 
oversight.

On the other hand, those controllers are out there and are in use by a 
lot of customers.  We can keep relying on luck, hoping that customers 
don't run into troubles or we can merge a few lines of code :)



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