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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?m+a3KRNnTMHVjYvMAVfwEnQgpSHLLG7BvT3vu7B4N+jzYx+K+ifVjr1Kg3+K?= =?us-ascii?Q?OYoB7VjnwXVFy3c3qpKqM8aygB/vA+nJQGn4nc58F9B9H7bRZ9LnxidTGWuT?= =?us-ascii?Q?ewnAEKT3ZfE4TdK94IOE39PSOQKlzvS27kf2m6uQaOOVZh7yXPMN5Jf6xFcc?= =?us-ascii?Q?3s/VvGEX30iqpwcduifFyOzvXFitVrRphbJybNTE/3MbqDEYigr6xGAjRBf7?= =?us-ascii?Q?FNkgf0/kPmeU0Ah75NMe+9tmpop6tUgYs8LI1IJO3RK8iiziLFJojgZ1NOmo?= =?us-ascii?Q?/v0+QCXCHNTRqKGxnrFhAgRwHZTdUxWh1OsAhqrwSgvWzInQjhRnOavOvs6x?= =?us-ascii?Q?gmNnpWJh7FbxuNkOh0gvzeBiIAK+rm+gw3UPlVH3MnO+rzKLPaWo7B0Oyhqv?= =?us-ascii?Q?1e9DbyTF+O7SyCLala1GiIP1UjwqSGceNcFTLU2Mv6f++KTyMe3pGIE7d08T?= =?us-ascii?Q?xFuyZbEEA1fY4EMkpYgzIwbSxPOc7AdJc4R1Nvb/asEAgERvP4wGvFhmFuGR?= =?us-ascii?Q?jCCzPc9P04WDpsiXL05ft0KT8mJeZ3ep2f73G4HA7IVHC/VaheGT6K1yNY6r?= =?us-ascii?Q?D0UAPJdUIHppWSwhn+Mc5Os6PwCo5QclxvOrA/ZNTwauO+8QNKq1OvGzSlWG?= =?us-ascii?Q?sRHR0X0KSrmY+dl595T9ijBi/GMPPgqwQ0JGQapJKiNQyHU0dbt23i8nFyAi?= =?us-ascii?Q?U2qZcxExppFT/uyS0FHXknJn4CRWKPclzqgLLP8/bzXN3zMab7dn1IhCfabF?= =?us-ascii?Q?/ZDYp4LNzt8zNSdxBZ4hPlgTCD4r7AoAJn1aYBBTaHvtbYETB7X9D1uDEebr?= =?us-ascii?Q?jY0GB1ciZ63RdPcYmH5YaDJIGG2UIUTBV0eZFB7WHEe/CrYgzcnpt3VcKzMb?= =?us-ascii?Q?rx0sM8QOY0tnk1qnEhLgIQ5iDHPd42VmTuxAHnScPc6EVqsSGgMtIUH5KxRD?= =?us-ascii?Q?74JKlrQCtutH1vHRzK8ybD3lfScR0CV0VD4PB1BrHUrRCx87na2t+rrNHN70?= =?us-ascii?Q?MOWXyBi2DU6Av0jRX50LV3R1MsFCdwLyLgzxOIE6r2O2DnMNbTzrQ2RL2o6y?= =?us-ascii?Q?STs1gCW4LIbQO3/yk1ACm2D+SIVNf7l0nuQGBMjukcVQQ01lCff6nim6fpPL?= =?us-ascii?Q?kollT1vzv9Du2PCjZs8/9sEEbyioC/GTNQWHHr9Aqaor64gM4HpBeIlvHdHO?= =?us-ascii?Q?4/igZCkqv78QvHkjZdJIKErFkvqFlhNB8PZnDPmB0bntGDN6awIiin0+PRaH?= =?us-ascii?Q?bB6JZ1Fd1lmScM+lFQ3x5Tb+43AzWxsQVfRnUUOaB9Tw/rQgipnB4Nwh/C+1?= =?us-ascii?Q?5xYRcPfJ+YgWULZvYUJCzkOdHe5WCay2n7yilqNiOUJBmR1prmWRE04ReXMe?= =?us-ascii?Q?YdN0HSKsPmhgDYJUNgNsCU3icy/CNPywVzAVNq4AaBXNWS8etTRSblZq2wnF?= =?us-ascii?Q?//0koIni7aY9XAoMwTrQzronBeUin1mpoWfYOWuwRrDA8uli5nMv7Plggnhy?= =?us-ascii?Q?tTKEQfMba06LbJhxdO40ZCmWPiAxYlBNf3yZqv5wV5q0N1nCMaaQoA+d1Pca?= =?us-ascii?Q?ZpPS/JqGl10XL9b6clLLcwWqdvzCNgFuu46wFZ2N?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: ec7d5772-26b1-4c47-0159-08dbc957cfa6 X-MS-Exchange-CrossTenant-AuthSource: HE1PR0402MB3497.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Oct 2023 06:11:58.8677 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 2HssnYlIKAxwBJODLMJZgA5KQSjCXq4k6C6fUjzjhOckL+83JZuDHOyFSA61MwOiTTc+bE2newG2DrYIHgeB/w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM9PR04MB8908 On Mon, Oct 09, 2023 at 06:13:19PM +0200, Matthieu Baerts wrote: > Hi Geliang, > > On 09/10/2023 08:02, Geliang Tang wrote: > > When closing the msk->first socket in __mptcp_close_ssk(), if there's > > another subflow available, it's better to avoid resetting it. > > > > Signed-off-by: Geliang Tang > > --- > > net/mptcp/protocol.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c > > index 30e0c29ae0a4..6346a164ed66 100644 > > --- a/net/mptcp/protocol.c > > +++ b/net/mptcp/protocol.c > > @@ -2396,7 +2396,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, > > goto out_release; > > } > > > > - dispose_it = msk->free_first || ssk != msk->first; > > + dispose_it = msk->free_first || ssk != msk->first || !list_is_singular(&msk->conn_list); > > if (dispose_it) > > list_del(&subflow->node); > > > > @@ -2446,7 +2446,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, > > > > sock_put(ssk); > > > > - if (ssk == msk->first) > > + if (ssk == msk->first && list_is_singular(&msk->conn_list)) > > WRITE_ONCE(msk->first, NULL); > > I don't think we should 'dispose it' nor set 'msk->first' to NULL but That's what this patch dose. Dispose it, not set msk->first to NULL. > instead, we should not call tcp_disconnect() directly: if the connection But this patch lacks the code to handle: ssk == msk->first && !list_is_singular(&msk->conn_list) Is my understanding correct? How about dropping list_is_singular() in the next block, something like: * For established sockets, allow an additional timeout before closing, * as the protocol can still create more subflows. */ - if (list_is_singular(&msk->conn_list) && msk->first && - inet_sk_state_load(msk->first) == TCP_CLOSE) { + if (msk->first && inet_sk_state_load(msk->first) == TCP_CLOSE) { if (sk->sk_state != TCP_ESTABLISHED || msk->in_accept_queue || sock_flag(sk, SOCK_DEAD)) { inet_sk_state_store(sk, TCP_CLOSE); > is still in ESTABLISHED, tcp_disconnect() will send a RST if I'm not > mistaken. That's what we want to avoid, no? Yes, tcp_disconnect will send a RST. Thanks, -Geliang > > Cheers, > Matt > -- > Tessares | Belgium | Hybrid Access Solutions > www.tessares.net