Re: [PATCH for-rc] RDMA/rxe: Fix failure during driver load

[Kamal Heib <kamalheib1@gmail.com>]

On Tue, Jun 01, 2021 at 04:11:08PM +0800, Zhu Yanjun wrote:
> On Tue, Jun 1, 2021 at 3:56 PM kamal heib <kamalheib1@gmail.com> wrote:
> >
> >
> >
> > > On 1 Jun 2021, at 10:45, Zhu Yanjun <zyjzyj2000@gmail.com> wrote:
> > >
> > > On Tue, Jun 1, 2021 at 1:58 PM Kamal Heib <kamalheib1@gmail.com> wrote:
> > >>
> > >> To avoid the following failure when trying to load the rdma_rxe module
> > >> while IPv6 is disabled, Add a check to make sure that IPv6 is enabled
> > >> before trying to create the IPv6 UDP tunnel.
> > >>
> > >> $ modprobe rdma_rxe
> > >> modprobe: ERROR: could not insert 'rdma_rxe': Operation not permitted
> > >
> > > About this problem, this link:
> > > https://patchwork.kernel.org/project/linux-rdma/patch/20210413234252.12209-1-yanjun.zhu@intel.com/
> > > also tries to solve ipv6 problem.
> > >
> > > Zhu Yanjun
> > >
> >
> > Yes, but this patch is fixing the problem more cleanly and I’ve tested it.
> >
> > Could you please review and ACK this patch?
> 
> https://www.spinics.net/lists/linux-rdma/msg100274.html
> Compared with the above commit, are the following also needed?
>

I don't think so, because we aren't going to reach this function.

Do you know about a real bug that fails in this function?!

Thanks,
Kamal

> diff --git a/drivers/infiniband/sw/rxe/rxe_net.c
> b/drivers/infiniband/sw/rxe/rxe_net.c
> index 0701bd1ffd1a..6ef092cb575e 100644
> --- a/drivers/infiniband/sw/rxe/rxe_net.c
> +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> @@ -72,6 +72,11 @@ static struct dst_entry *rxe_find_route6(struct
> net_device *ndev,
>         struct dst_entry *ndst;
>         struct flowi6 fl6 = { { 0 } };
> 
> +       if (!ipv6_mod_enabled()) {
> +               pr_info("IPv6 is disabled by ipv6.disable=1 in cmdline");
> +               return NULL;
> +       }
> +
>         memset(&fl6, 0, sizeof(fl6));
>         fl6.flowi6_oif = ndev->ifindex;
>         memcpy(&fl6.saddr, saddr, sizeof(*saddr));
> 
> Zhu Yanjun
> 
> >
> > Thanks,
> > Kamal
> >
> >
> > >>
> > >> Fixes: dfdd6158ca2c ("IB/rxe: Fix kernel panic in udp_setup_tunnel")
> > >> Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
> > >> ---
> > >> drivers/infiniband/sw/rxe/rxe_net.c | 14 ++++++++------
> > >> 1 file changed, 8 insertions(+), 6 deletions(-)
> > >>
> > >> diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> > >> index 01662727dca0..f353fc18769f 100644
> > >> --- a/drivers/infiniband/sw/rxe/rxe_net.c
> > >> +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> > >> @@ -617,12 +617,14 @@ static int rxe_net_ipv6_init(void)
> > >> {
> > >> #if IS_ENABLED(CONFIG_IPV6)
> > >>
> > >> -       recv_sockets.sk6 = rxe_setup_udp_tunnel(&init_net,
> > >> -                                               htons(ROCE_V2_UDP_DPORT), true);
> > >> -       if (IS_ERR(recv_sockets.sk6)) {
> > >> -               recv_sockets.sk6 = NULL;
> > >> -               pr_err("Failed to create IPv6 UDP tunnel\n");
> > >> -               return -1;
> > >> +       if (ipv6_mod_enabled()) {
> > >> +               recv_sockets.sk6 = rxe_setup_udp_tunnel(&init_net,
> > >> +                                       htons(ROCE_V2_UDP_DPORT), true);
> > >> +               if (IS_ERR(recv_sockets.sk6)) {
> > >> +                       recv_sockets.sk6 = NULL;
> > >> +                       pr_err("Failed to create IPv6 UDP tunnel\n");
> > >> +                       return -1;
> > >> +               }
> > >>        }
> > >> #endif
> > >>        return 0;
> > >> --
> > >> 2.26.3
> > >>