Re: FW: [PATCH for-next] RDMA/rxe: Remove pkey table

[Kamal Heib <kamalheib1@gmail.com>]

On Tue, Jul 28, 2020 at 11:46:36PM +0800, Zhu Yanjun wrote:
> On 7/28/2020 9:44 PM, Kamal Heib wrote:
> > On Tue, Jul 28, 2020 at 09:21:06PM +0800, Zhu Yanjun wrote:
> > > On 7/28/2020 4:35 PM, Kamal Heib wrote:
> > > > On Thu, Jul 23, 2020 at 11:15:00PM +0800, Zhu Yanjun wrote:
> > > > > On 7/23/2020 9:15 PM, Jason Gunthorpe wrote:
> > > > > > On Thu, Jul 23, 2020 at 09:08:39PM +0800, Zhu Yanjun wrote:
> > > > > > > On 7/23/2020 3:25 PM, Kamal Heib wrote:
> > > > > > > > On Thu, Jul 23, 2020 at 02:58:41PM +0800, Zhu Yanjun wrote:
> > > > > > > > > On 7/23/2020 1:57 PM, Kamal Heib wrote:
> > > > > > > > > > On Wed, Jul 22, 2020 at 10:09:04AM +0800, Zhu Yanjun wrote:
> > > > > > > > > > > On Tue, Jul 21, 2020 at 7:28 PM Yanjun Zhu <yanjunz@mellanox.com> wrote:
> > > > > > > > > > > > From: Kamal Heib <kamalheib1@gmail.com>
> > > > > > > > > > > > Sent: Tuesday, July 21, 2020 6:16 PM
> > > > > > > > > > > > To: linux-rdma@vger.kernel.org
> > > > > > > > > > > > Cc: Yanjun Zhu <yanjunz@mellanox.com>; Doug Ledford <dledford@redhat.com>; Jason Gunthorpe <jgg@ziepe.ca>; Kamal Heib <kamalheib1@gmail.com>
> > > > > > > > > > > > Subject: [PATCH for-next] RDMA/rxe: Remove pkey table
> > > > > > > > > > > > 
> > > > > > > > > > > > The RoCE spec require from RoCE devices to support only the defualt pkey, While the rxe driver maintain a 64 enties pkey table and use only the first entry. With that said remove the maintaing of the pkey table and used the default pkey when needed.
> > > > > > > > > > > > 
> > > > > > > > > > > Hi Kamal
> > > > > > > > > > > 
> > > > > > > > > > > After this patch is applied, do you make tests with SoftRoCE and mlx hardware?
> > > > > > > > > > > 
> > > > > > > > > > > The SoftRoCE should work well with the mlx hardware.
> > > > > > > > > > > 
> > > > > > > > > > > Zhu Yanjun
> > > > > > > > > > > 
> > > > > > > > > > Hi Zhu,
> > > > > > > > > > 
> > > > > > > > > > Yes, please see below:
> > > > > > > > > > 
> > > > > > > > > > $ ibv_rc_pingpong -d mlx5_0 -g 11
> > > > > > > > > >        local address:  LID 0x0000, QPN 0x0000e3, PSN 0x728a4f, GID ::ffff:172.31.40.121
> > > > > > > > > Can you make tests with GSI QP?
> > > > > > > > > 
> > > > > > > > > Zhu Yanjun
> > > > > > > > > 
> > > > > > > Is this the GSI ?
> > > > > > > 
> > > > > > > Please check GSI in "InfiniBandTM Architecture Specification Volume 1
> > > > > > > Release 1.3"
> > > > > > > 
> > > > > > > Then make tests with GSI again.
> > > > > The followings are also removed by this commit. Not sure if it is good.
> > > > > 
> > > > > "
> > > > > 
> > > > > C9-42: If the destination QP is QP1, the BTH:P_Key shall be compared to the
> > > > > set of P_Keys associated with the port on which the packet arrived. If the
> > > > > P_Key matches any of the keys associated with the port, it shall be
> > > > > considered valid.
> > > > > 
> > > > > "
> > > > > 
> > > > The above is correct for ports that configured to work in InfiniBand
> > > > mode, while in RoCEv2 mode only the default P_Key should be associated
> > > > with the port (Please see below from "ANNEX A17:   ROCEV2 (IP ROUTABLE
> > > > ROCE)):
> > > > 
> > > > """
> > > > 17.7.1 LOADING THE P_KEY TABLE
> > > > 
> > > > Compliance statement C17-7: on page 1193 describes requirements for
> > > > setting the P_Key table based on an assumption that the P_Key table is
> > > > set directly by a Subnet Manager. However, RoCEv2 ports do not support
> > > > InfiniBand Subnet Management. Therefore, compliance statement C17-7:
> > > > on page 1193 does not apply to RoCEv2 ports.
> > > "
> > > 
> > > C17-7: An HCA shall require no OS involvement to set the P_Key table;
> > > 
> > > the P_Key table shall be set directly by Subnet Manager MADs.
> > > 
> > > "
> > > 
> > > In SoftRoCE, what set the P_Key table?
> > > 
> > No one is setting the P_Key table in SoftRoCE, and no subnet manager in
> > the RoCE fabric.
> > 
> > Could you please tell me what is wrong with this patch?
> 
> Please read the mail thread again.
> 
> GSI QP number is 1. In your commits, the handle of qpn == 1 is removed.
> 
> It seems that it conflicts with IB specification.
> 
> Not sure if it is good.
>

Could you please read my patch again and point to what do you think is
wrong?

What I did in this patch is to verify that the pkey value in the
received packet is the default P_Key regardless of the qpn, because RoCE
devices should maintain only the default P_Key.

Thanks,
Kamal

> > 
> > Thanks,
> > Kamal
> > 
> > > > Methods for setting the P_Key table associated with a RoCEv2 port are
> > > > not defined in this specification, except for the requirements for a
> > > > default P_Key described elsewhere in this annex.
> > > > """
> > > > 
> > > > Thanks,
> > > > Kamal
> > > > 
> > > > 
> > > > > > rping uses RDMA CM which goes over the GSI
> > > > > > 
> > > > > > Jason
> 
>