Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20201126063557.1283-1-ms@dev.tdt.de> <20201126063557.1283-5-ms@dev.tdt.de>
In-Reply-To: <20201126063557.1283-5-ms@dev.tdt.de>
From:   Xie He <xie.he.0141@gmail.com>
Date:   Wed, 9 Dec 2020 01:01:11 -0800
Message-ID: <CAJht_EMZqcPdE5n3Vp+jJa1sVk9+vbwd-Gbi8Xqy19bEdbNNuA@mail.gmail.com>
Subject: Re: [PATCH net-next v7 4/5] net/x25: fix restart request/confirm handling
To:     Martin Schiller <ms@dev.tdt.de>
Cc:     Andrew Hendry <andrew.hendry@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Linux X25 <linux-x25@vger.kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, Nov 25, 2020 at 10:36 PM Martin Schiller <ms@dev.tdt.de> wrote:
>
> We have to take the actual link state into account to handle
> restart requests/confirms well.
>
> @@ -214,8 +241,6 @@ void x25_link_established(struct x25_neigh *nb)
>  {
>         switch (nb->state) {
>         case X25_LINK_STATE_0:
> -               nb->state = X25_LINK_STATE_2;
> -               break;
>         case X25_LINK_STATE_1:
>                 x25_transmit_restart_request(nb);
>                 nb->state = X25_LINK_STATE_2;

What is the reason for this change? Originally only the connecting
side will transmit a Restart Request; the connected side will not and
will only wait for the Restart Request to come. Now both sides will
transmit Restart Requests at the same time. I think we should better
avoid collision situations like this.