Re: [PATCHv5 for-next 1/1] RDMA/rxe: Disable ipv6 features when ipv6.disable in cmdline

[Zhu Yanjun <zyjzyj2000@gmail.com>]

On Tue, Apr 13, 2021 at 6:48 PM Leon Romanovsky <leon@kernel.org> wrote:
>
> On Tue, Apr 13, 2021 at 07:42:52PM -0400, Zhu Yanjun wrote:
> > From: Zhu Yanjun <zyjzyj2000@gmail.com>
> >
> > When ipv6.disable=1 is set in cmdline, ipv6 is actually disabled
> > in the stack. As such, the operations of ipv6 in RXE will fail.
> > So ipv6 features in RXE should also be disabled in RXE.
> >
> > Link: https://lore.kernel.org/linux-rdma/880d7b59-4b17-a44f-1a91-88257bfc3aaa@redhat.com/T/#t
> > Fixes: 8700e3e7c4857 ("Soft RoCE driver")
> > Reported-by: Yi Zhang <yi.zhang@redhat.com>
> > Signed-off-by: Zhu Yanjun <zyjzyj2000@gmail.com>
> > ---
> > V4->V5: Clean up signature block and remove error message
> > V3->V4: Check the returned value instead of ipv6 module
> > V2->V3: Remove print message
> > V1->V2: Modify the pr_info messages
> > ---
> >  drivers/infiniband/sw/rxe/rxe_net.c | 13 ++++++++++++-
> >  1 file changed, 12 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> > index 01662727dca0..984c3ac449bd 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_net.c
> > +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> > @@ -208,7 +208,13 @@ static struct socket *rxe_setup_udp_tunnel(struct net *net, __be16 port,
> >       /* Create UDP socket */
> >       err = udp_sock_create(net, &udp_cfg, &sock);
> >       if (err < 0) {
> > -             pr_err("failed to create udp socket. err = %d\n", err);
> > +             /* If UDP tunnel over ipv6 fails with -EAFNOSUPPORT, the tunnel
> > +              * over ipv4 still works. This error message will not pop out.
> > +              * If UDP tunnle over ipv4 fails or other errors with ipv6
> > +              * tunnel, this error should pop out.
> > +              */
> > +             if (!((err == -EAFNOSUPPORT) && (ipv6)))
>
> You have too much brackets.

My code corresponds with the comments.

Zhu Yanjun

>
> if (err != -EAFNOSUPPORT || !ipv6)))
>
> > +                     pr_err("failed to create udp socket. err = %d\n", err);
> >               return ERR_PTR(err);
> >       }
> >
> > @@ -620,6 +626,11 @@ static int rxe_net_ipv6_init(void)
> >       recv_sockets.sk6 = rxe_setup_udp_tunnel(&init_net,
> >                                               htons(ROCE_V2_UDP_DPORT), true);
> >       if (IS_ERR(recv_sockets.sk6)) {
> > +             /* Though IPv6 is not supported, IPv4 still needs to continue
> > +              */
> > +             if (PTR_ERR(recv_sockets.sk6) == -EAFNOSUPPORT)
> > +                     return 0;
> > +
> >               recv_sockets.sk6 = NULL;
> >               pr_err("Failed to create IPv6 UDP tunnel\n");
> >               return -1;
> > --
> > 2.27.0
> >