Re: [PATCH v7 1/5] mptcp: fix ADD_ADDR and RM_ADDR maybe flush addr_signal each other

[Geliang Tang <geliangtang@gmail.com>]

Yonglong Li <liyonglong@chinatelecom.cn> 于2021年6月30日周三 下午6:24写道：

>
> ADD_ADDR share pm.addr_signal with RM_ADDR, so after RM_ADDR/ADD_ADDR
> done we should not clean ADD_ADDR/RM_ADDR's addr_signal.
>
> Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
> ---
>  net/mptcp/pm.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
> index 9d00fa6..50079e5 100644
> --- a/net/mptcp/pm.c
> +++ b/net/mptcp/pm.c
> @@ -253,6 +253,7 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>                               struct mptcp_addr_info *saddr, bool *echo, bool *port)
>  {
>         int ret = false;
> +       u8 add_addr;
>
>         spin_lock_bh(&msk->pm.lock);
>
> @@ -267,7 +268,8 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>                 goto out_unlock;
>
>         *saddr = msk->pm.local;
> -       WRITE_ONCE(msk->pm.addr_signal, 0);
> +       add_addr = msk->pm.addr_signal & ~(BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
> +       WRITE_ONCE(msk->pm.addr_signal, add_addr);
>         ret = true;
>
>  out_unlock:

This part is removed in patch 3, why we need to add it here?

> @@ -279,6 +281,7 @@ bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>                              struct mptcp_rm_list *rm_list)
>  {
>         int ret = false, len;
> +       u8 rm_addr;
>
>         spin_lock_bh(&msk->pm.lock);
>
> @@ -286,16 +289,17 @@ bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>         if (!mptcp_pm_should_rm_signal(msk))
>                 goto out_unlock;
>
> +       rm_addr = msk->pm.addr_signal & ~BIT(MPTCP_RM_ADDR_SIGNAL);
>         len = mptcp_rm_addr_len(&msk->pm.rm_list_tx);
>         if (len < 0) {
> -               WRITE_ONCE(msk->pm.addr_signal, 0);
> +               WRITE_ONCE(msk->pm.addr_signal, rm_addr);
>                 goto out_unlock;
>         }
>         if (remaining < len)
>                 goto out_unlock;
>
>         *rm_list = msk->pm.rm_list_tx;
> -       WRITE_ONCE(msk->pm.addr_signal, 0);
> +       WRITE_ONCE(msk->pm.addr_signal, rm_addr);
>         ret = true;
>
>  out_unlock:
> --
> 1.8.3.1
>