Weirdness with discard cmd and get log pages

[Keith Busch]

On Thu, Oct 13, 2016 at 08:46:30AM -0700, Nisha Miller wrote:
> In the case of discard command, we are able to fetch the first two
> ranges (i.e 16 bytes/range x 2) correctly using DMA. But any ranges
> after that contain just junk data. For example, if we try to fetch 4
> ranges, ranges 1-2 are valid but ranges 3-4 contain junk.

How did you set up a discard command with more than one range? The
standard discard path to the driver allows only one.