RE: [PATCH v5] libibverbs: display gid type in ibv_devinfo

[Parav Pandit <parav@mellanox.com>]

> From: Jason Gunthorpe <jgg@mellanox.com>
> Sent: Monday, February 3, 2020 11:34 PM
> 
> On Mon, Feb 03, 2020 at 11:31:06PM +0530, Devesh Sharma wrote:
> > On Mon, Feb 3, 2020 at 11:23 PM Jason Gunthorpe <jgg@mellanox.com>
> wrote:
> > >
> > > On Mon, Feb 03, 2020 at 12:52:04PM -0500, Devesh Sharma wrote:
> > > > It becomes difficult to make out from the output of ibv_devinfo if
> > > > a particular gid index is RoCE v2 or not.
> > > >
> > > > Adding a string to the output of ibv_devinfo -v to display the gid
> > > > type at the end of gid.
> > > >
> > > > The output would look something like below:
> > > > $ ibv_devinfo -v -d bnxt_re2
> > > > hca_id: bnxt_re2
> > > >  transport:             InfiniBand (0)
> > > >  fw_ver:                216.0.220.0
> > > >  node_guid:             b226:28ff:fed3:b0f0
> > > >  sys_image_guid:        b226:28ff:fed3:b0f0
> > > >   .
> > > >   .
> > > >   .
> > > >   .
> > > >        phys_state:      LINK_UP (5)
> > > >        GID[  0]:               fe80::b226:28ff:fed3:b0f0, IB/RoCE v1
> > > >        GID[  1]:               fe80::b226:28ff:fed3:b0f0, RoCE v2
> > > >        GID[  2]:               ::ffff:192.170.1.101, IB/RoCE v1
> > > >        GID[  3]:               ::ffff:192.170.1.101, RoCE v2
> > >
> > > v1 GIDs are GIDs and should never be formed as IPv6 addreses..
> > So, V1 gids would fall back to old style of display and there will be
> > one more check for gid-type inside the loop...
> 
> Yes
> 
> Parav should we show both the v6 and classic format for a v2 GID? ie
> 
>         GID[  3]:               0000:0000:0000:ffff:xxxx:xxxx:xxxx, RoCE v2
>                                 ::ffff:192.170.1.101
> 
Due to lack of support of GID's netdev, v1/v2 type info in ibv_devinfo output, most users that I know of are using non upstream show_gids script.
So changing format here shouldn't break the existing users scripts.
There may be some scripts that may find this format different.
So I think printing both is likely a more safer option.

> Lets also supress the 'IB/RoCE v1' string on !roce device. IB only has one GID
> type, there is no reason to print anything
> 
> Jason