On Wed, Jan 15, 2020 at 11:56 AM Vivek Goyal <vgoyal(a)redhat.com> wrote:
> Even the Red Hat
> installation guide example shows mounting on pmem0 directly. 
Below that example it also says.
"When creating partitions on a pmem device to be used for direct access,
partitions must be aligned on page boundaries. On the Intel 64 and AMD64
architecture, at least 4KiB alignment for the start and end of the
partition, but 2MiB is the preferred alignment. By default, the parted
tool aligns partitions on 1MiB boundaries. For the first partition,
specify 2MiB as the start of the partition. If the size of the partition
is a multiple of 2MiB, all other partitions are also aligned."
So documentation is clearly saying dax will work with partitions as well.
And some user might decide to just do that.
Yes, of course but my point is that it was ambiguous.
I'm going to take a look at how hard it would be to develop a kpartx
fallback in udev. If that can live across the driver transition then
maybe this can be a non-event for end users that already have that
udev update deployed.