On 11/19/2018 5:41 PM, Jason Gunthorpe wrote:
On Mon, Nov 19, 2018 at 08:16:37AM -0800, Bart Van Assche wrote:
On Mon, 2018-11-19 at 10:45 -0500, Chuck Lever wrote:
FMR is not supported on most recent RDMA devices. It is also slower
and less secure than FRWR. As discussed during the RDMA BoF at LPC
2018, it is time to remove support for FMR in the NFS/RDMA client
stack. NFS/RDMA server-side uses either local memory registration or
FRWR. There is no change required there to deprecate FMR.
There are a few Infiniband/RoCE devices in the kernel tree that do
not support MEM_MGT_EXTENSIONS, and therefore will no longer support
client-side NFS/RDMA. These are:
- mthca
- qib
Ooh, qib was not in the list when we talked on this in plumbers. That
does change things.
Dennis: Could qib be changed? HFI1 supports FRWR right?
Turns out that qib can not support FRWR because that requires HW support
for opcodes that qib just doesn't understand.
hfi1 is good to go though.
- usnic
- hns (RoCE)
Can someone from Intel comment on how many of their customers rely on the qib
driver?
There is a user base. I can't say how large though. But I have had
discussions with mgmt and we aren't quite ready to leave qib out in the
cold just yet.
We have a lot of people out this week due to the US Thanksgiving
holiday. Once people are back in the office on Monday I'll find out some
more as to the impact of this change.
-Denny
