Re: [PATCH net-next 2/2] mctp: test: defer mdev setup until we've registered

[David Gow <davidgow@google.com>]

On Sat, Oct 2, 2021 at 10:27 AM Jeremy Kerr <jk@codeconstruct.com.au> wrote:
>
> The MCTP device isn't available until we've registered the netdev, so
> defer storing our convenience pointer.
>
> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
> ---

Haha -- you sent this just as I'd come up with the same patch here. :-)

With these changes, alongside the rt->dev == NULL in
mctp_route_release() crash fix mentioned in [1], the tests all pass on
my system. (They also pass under KASAN, which bodes well.)

This fix is,
Reviewed-by: David Gow <davidgow@google.com>

Cheers,
-- David

[1]: https://lore.kernel.org/linux-kselftest/163309440949.24017.15314464452259318665.git-patchwork-notify@kernel.org/T/#m1a319b6932dd2bffaf78ab2d3b4c399282f7bda2



>  net/mctp/test/utils.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/net/mctp/test/utils.c b/net/mctp/test/utils.c
> index e2ab1f3da357..cc6b8803aa9d 100644
> --- a/net/mctp/test/utils.c
> +++ b/net/mctp/test/utils.c
> @@ -46,17 +46,17 @@ struct mctp_test_dev *mctp_test_create_dev(void)
>         dev = netdev_priv(ndev);
>         dev->ndev = ndev;
>
> -       rcu_read_lock();
> -       dev->mdev = __mctp_dev_get(ndev);
> -       mctp_dev_hold(dev->mdev);
> -       rcu_read_unlock();
> -
>         rc = register_netdev(ndev);
>         if (rc) {
>                 free_netdev(ndev);
>                 return NULL;
>         }
>
> +       rcu_read_lock();
> +       dev->mdev = __mctp_dev_get(ndev);
> +       mctp_dev_hold(dev->mdev);
> +       rcu_read_unlock();
> +
>         return dev;
>  }
>
> --
> 2.30.2
>