Re: v5.9-rc1 commit reliably breaks pci nvme detection

From: John Garry
Date: Fri Aug 21 2020 - 03:30:29 EST


On 20/08/2020 18:12, Christoph Hellwig wrote:
On Thu, Aug 20, 2020 at 11:10:58AM -0600, Jens Axboe wrote:
To be fair, I've only heard this one complaint about it, so hopefully it's
not too widespread. I'm on an x86-64 laptop myself with nvme, and it works
just fine:-)
The cause for this is the weird NVMe of by ones, where 0 in a field
means 1.

I thought that this was a common trick by spec writers to fit a number in range (0, 2^x] in x bits (as opposed to x+1).