Re: [PATCH] net/sched: cls: Load net classifier modules via alias

[Jamal Hadi Salim]

On Tue, Nov 21, 2023 at 12:56 PM Michal Koutný <mkoutny@xxxxxxxx> wrote:
>
> The classifier modules may be loaded lazily without user's awareness and
> control. Add respective aliases to modules and request them under these
> aliases so that modprobe's blacklisting mechanism works also for
> classifier modules. (The same pattern exists e.g. for filesystem
> modules.)
>

Hi Michal,
Dumb question: What's speacial about the "tcf- '' that makes it work
better for filtering than existing "cls_" prefix? What about actions
(prefix "act_") etc?

cheers,
jamal

> Original module names remain unchanged.
>
> Signed-off-by: Michal Koutný <mkoutny@xxxxxxxx>
> ---
>  include/net/pkt_cls.h    | 1 +
>  net/sched/cls_api.c      | 2 +-
>  net/sched/cls_basic.c    | 1 +
>  net/sched/cls_bpf.c      | 1 +
>  net/sched/cls_cgroup.c   | 1 +
>  net/sched/cls_flow.c     | 1 +
>  net/sched/cls_flower.c   | 1 +
>  net/sched/cls_fw.c       | 1 +
>  net/sched/cls_matchall.c | 1 +
>  net/sched/cls_route.c    | 1 +
>  net/sched/cls_u32.c      | 1 +
>  11 files changed, 11 insertions(+), 1 deletion(-)
>
> This is primarily for TC subsystem maintainers where the
> request_module() resides but Cc list is large because of touches in
> various classifier modules.
>
> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
> index a76c9171db0e..424b4f889feb 100644
> --- a/include/net/pkt_cls.h
> +++ b/include/net/pkt_cls.h
> @@ -24,6 +24,7 @@ struct tcf_walker {
>
>  int register_tcf_proto_ops(struct tcf_proto_ops *ops);
>  void unregister_tcf_proto_ops(struct tcf_proto_ops *ops);
> +#define MODULE_ALIAS_TCF(kind) MODULE_ALIAS("tcf-" __stringify(kind))
>
>  struct tcf_block_ext_info {
>         enum flow_block_binder_type binder_type;
> diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
> index 1976bd163986..02fdcceee083 100644
> --- a/net/sched/cls_api.c
> +++ b/net/sched/cls_api.c
> @@ -257,7 +257,7 @@ tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
>  #ifdef CONFIG_MODULES
>         if (rtnl_held)
>                 rtnl_unlock();
> -       request_module("cls_%s", kind);
> +       request_module("tcf-%s", kind);
>         if (rtnl_held)
>                 rtnl_lock();
>         ops = __tcf_proto_lookup_ops(kind);
> diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
> index a1f56931330c..a3500ac7fc1a 100644
> --- a/net/sched/cls_basic.c
> +++ b/net/sched/cls_basic.c
> @@ -328,6 +328,7 @@ static struct tcf_proto_ops cls_basic_ops __read_mostly = {
>         .bind_class     =       basic_bind_class,
>         .owner          =       THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("basic");
>
>  static int __init init_basic(void)
>  {
> diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c
> index 382c7a71f81f..8d57ac155c0c 100644
> --- a/net/sched/cls_bpf.c
> +++ b/net/sched/cls_bpf.c
> @@ -693,6 +693,7 @@ static struct tcf_proto_ops cls_bpf_ops __read_mostly = {
>         .dump           =       cls_bpf_dump,
>         .bind_class     =       cls_bpf_bind_class,
>  };
> +MODULE_ALIAS_TCF("bpf");
>
>  static int __init cls_bpf_init_mod(void)
>  {
> diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
> index 7ee8dbf49ed0..0ded7d79894c 100644
> --- a/net/sched/cls_cgroup.c
> +++ b/net/sched/cls_cgroup.c
> @@ -209,6 +209,7 @@ static struct tcf_proto_ops cls_cgroup_ops __read_mostly = {
>         .dump           =       cls_cgroup_dump,
>         .owner          =       THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("cgroup");
>
>  static int __init init_cgroup_cls(void)
>  {
> diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
> index 6ab317b48d6c..2806aa1254e1 100644
> --- a/net/sched/cls_flow.c
> +++ b/net/sched/cls_flow.c
> @@ -702,6 +702,7 @@ static struct tcf_proto_ops cls_flow_ops __read_mostly = {
>         .walk           = flow_walk,
>         .owner          = THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("flow");
>
>  static int __init cls_flow_init(void)
>  {
> diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
> index e5314a31f75a..739e09e0fa57 100644
> --- a/net/sched/cls_flower.c
> +++ b/net/sched/cls_flower.c
> @@ -3633,6 +3633,7 @@ static struct tcf_proto_ops cls_fl_ops __read_mostly = {
>         .owner          = THIS_MODULE,
>         .flags          = TCF_PROTO_OPS_DOIT_UNLOCKED,
>  };
> +MODULE_ALIAS_TCF("flower");
>
>  static int __init cls_fl_init(void)
>  {
> diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
> index afc534ee0a18..86c833885a2d 100644
> --- a/net/sched/cls_fw.c
> +++ b/net/sched/cls_fw.c
> @@ -433,6 +433,7 @@ static struct tcf_proto_ops cls_fw_ops __read_mostly = {
>         .bind_class     =       fw_bind_class,
>         .owner          =       THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("fw");
>
>  static int __init init_fw(void)
>  {
> diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c
> index c4ed11df6254..21ba73978c6a 100644
> --- a/net/sched/cls_matchall.c
> +++ b/net/sched/cls_matchall.c
> @@ -398,6 +398,7 @@ static struct tcf_proto_ops cls_mall_ops __read_mostly = {
>         .bind_class     = mall_bind_class,
>         .owner          = THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("matchall");
>
>  static int __init cls_mall_init(void)
>  {
> diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
> index 12a505db4183..a4701c0752df 100644
> --- a/net/sched/cls_route.c
> +++ b/net/sched/cls_route.c
> @@ -671,6 +671,7 @@ static struct tcf_proto_ops cls_route4_ops __read_mostly = {
>         .bind_class     =       route4_bind_class,
>         .owner          =       THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("route");
>
>  static int __init init_route4(void)
>  {
> diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
> index d5bdfd4a7655..a969adbd7423 100644
> --- a/net/sched/cls_u32.c
> +++ b/net/sched/cls_u32.c
> @@ -1453,6 +1453,7 @@ static struct tcf_proto_ops cls_u32_ops __read_mostly = {
>         .bind_class     =       u32_bind_class,
>         .owner          =       THIS_MODULE,
>  };
> +MODULE_ALIAS_TCF("u32");
>
>  static int __init init_u32(void)
>  {
> --
> 2.42.1
>