Re: [PATCH mptcp-next v4 0/5] Squash to "Add mptcp_subflow bpf_iter support"

[Geliang Tang <geliang@kernel.org>]

Hi Matt,

On Mon, 2025-02-24 at 11:37 +0800, Geliang Tang wrote:
> From: Geliang Tang <tanggeliang@kylinos.cn>
> 
> v4:
>  - drop sock_owned_by_user_nocheck and spin_is_locked. According to
>    comments from Mat and Martin, in this set mptcp_subflow
>    bpf_iter only used from a cg sockopt bpf prog, no need to add
> these
>    check at this moment.
> 
> v3:
>  - patch 3, continue to use sock_owned_by_user_nocheck() and
> spin_is_locked()
> checks instead of using msk_owned_by_me().
>  - patch 5, drop declaration of bpf_mptcp_subflow_tcp_sock. It's no
> longer
> used.
>  - patch 5, update the comment for mptcp_subflow_tcp_sock(), which is
> a BPF
> helper, not a kfunc.
> 
> The commit log of "bpf: Register mptcp common kfunc set" doesn't
> match the
> code, please update it as:
> 
> '''
> bpf: Register mptcp common kfunc set
> 
> MPTCP helper mptcp_subflow_ctx() is used to convert struct sock to
> struct mptcp_subflow_context. It will be used in MPTCP BPF programs.
> 
> This patch defines corresponding wrapper of this helper, and put it
> into the newly defined mptcp common kfunc set and register this set
> with the flag BPF_PROG_TYPE_CGROUP_SOCKOPT to let it accessible to
> the 'cgroup/getsockopt' type of BPF programs.
> '''

Thanks for applying this set. Please update this commit log too.

-Geliang

> 
> v2:
>  - Drop bpf_skc_to_mptcp_sock
>  - Check the owner before assigning the msk as Mat suggested.
>  - Use bpf_core_cast() in mptcp_subflow bpf_iter subtest instead of
> using bpf_skc_to_mptcp_sock().
> 
> Address Martin's suggestions for "Add mptcp_subflow bpf_iter support"
> v2.
> 
> Geliang Tang (5):
>   Revert "bpf: Extend bpf_skc_to_mptcp_sock to MPTCP sock"
>   Revert "bpf: Allow use of skc_to_mptcp_sock in cg_sockopt"
>   Squash to "bpf: Add mptcp_subflow bpf_iter"
>   Revert "bpf: Acquire and release mptcp socket"
>   Squash to "selftests/bpf: Add mptcp_subflow bpf_iter subtest"
> 
>  include/net/mptcp.h                           |  4 +-
>  kernel/bpf/cgroup.c                           |  2 -
>  net/core/filter.c                             |  2 +-
>  net/mptcp/bpf.c                               | 41 ++++-------------
> --
>  .../testing/selftests/bpf/bpf_experimental.h  |  2 +-
>  tools/testing/selftests/bpf/progs/mptcp_bpf.h |  5 ---
>  .../selftests/bpf/progs/mptcp_bpf_iters.c     | 10 ++---
>  7 files changed, 15 insertions(+), 51 deletions(-)
>