When working on a fix modifying mptcp_check_data_fin(), I noticed the
returned value was no longer used.
It looks like it was used for 3 days, between commit 7ed90803a213
("mptcp: send explicit ack on delayed ack_seq incr") and commit
ea4ca586b16f ("mptcp: refine MPTCP-level ack scheduling").
This returned value can be safely removed.
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
net/mptcp/protocol.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 1c26acf6c4145896ecbb5c7f7004121c66a20649..f3dda47ad1d70b5c6a326c17dbe6d244c5638ca2 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -530,11 +530,10 @@ static void mptcp_cleanup_rbuf(struct mptcp_sock *msk, int copied)
}
}
-static bool mptcp_check_data_fin(struct sock *sk)
+static void mptcp_check_data_fin(struct sock *sk)
{
struct mptcp_sock *msk = mptcp_sk(sk);
u64 rcv_data_fin_seq;
- bool ret = false;
/* Need to ack a DATA_FIN received from a peer while this side
* of the connection is in ESTABLISHED, FIN_WAIT1, or FIN_WAIT2.
@@ -572,12 +571,10 @@ static bool mptcp_check_data_fin(struct sock *sk)
break;
}
- ret = true;
if (!__mptcp_check_fallback(msk))
mptcp_send_ack(msk);
mptcp_close_wake_up(sk);
}
- return ret;
}
static void mptcp_dss_corruption(struct mptcp_sock *msk, struct sock *ssk)
---
base-commit: e9091ee333eb716a0933dcb08617228dcd3d3623
change-id: 20250906-check_data_fin_ret-6d284170880a
Best regards,
--
Matthieu Baerts (NGI0) <matttbe@kernel.org>
Hi Matt,
On Sat, 2025-09-06 at 16:13 +0200, Matthieu Baerts (NGI0) wrote:
> When working on a fix modifying mptcp_check_data_fin(), I noticed the
> returned value was no longer used.
>
> It looks like it was used for 3 days, between commit 7ed90803a213
> ("mptcp: send explicit ack on delayed ack_seq incr") and commit
> ea4ca586b16f ("mptcp: refine MPTCP-level ack scheduling").
>
> This returned value can be safely removed.
>
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
LGTM!
Reviewed-by: Geliang Tang <geliang@kernel.org>
Thanks,
-Geliang
> ---
> net/mptcp/protocol.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
> index
> 1c26acf6c4145896ecbb5c7f7004121c66a20649..f3dda47ad1d70b5c6a326c17dbe
> 6d244c5638ca2 100644
> --- a/net/mptcp/protocol.c
> +++ b/net/mptcp/protocol.c
> @@ -530,11 +530,10 @@ static void mptcp_cleanup_rbuf(struct
> mptcp_sock *msk, int copied)
> }
> }
>
> -static bool mptcp_check_data_fin(struct sock *sk)
> +static void mptcp_check_data_fin(struct sock *sk)
> {
> struct mptcp_sock *msk = mptcp_sk(sk);
> u64 rcv_data_fin_seq;
> - bool ret = false;
>
> /* Need to ack a DATA_FIN received from a peer while this
> side
> * of the connection is in ESTABLISHED, FIN_WAIT1, or
> FIN_WAIT2.
> @@ -572,12 +571,10 @@ static bool mptcp_check_data_fin(struct sock
> *sk)
> break;
> }
>
> - ret = true;
> if (!__mptcp_check_fallback(msk))
> mptcp_send_ack(msk);
> mptcp_close_wake_up(sk);
> }
> - return ret;
> }
>
> static void mptcp_dss_corruption(struct mptcp_sock *msk, struct sock
> *ssk)
>
> ---
> base-commit: e9091ee333eb716a0933dcb08617228dcd3d3623
> change-id: 20250906-check_data_fin_ret-6d284170880a
>
> Best regards,
Hi Matt,
On Wed, 2025-09-10 at 11:38 +0800, Geliang Tang wrote:
> Hi Matt,
>
> On Sat, 2025-09-06 at 16:13 +0200, Matthieu Baerts (NGI0) wrote:
> > When working on a fix modifying mptcp_check_data_fin(), I noticed
> > the
> > returned value was no longer used.
> >
> > It looks like it was used for 3 days, between commit 7ed90803a213
> > ("mptcp: send explicit ack on delayed ack_seq incr") and commit
> > ea4ca586b16f ("mptcp: refine MPTCP-level ack scheduling").
> >
> > This returned value can be safely removed.
> >
> > Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
>
> LGTM!
>
> Reviewed-by: Geliang Tang <geliang@kernel.org>
Please update the subject when applying this patch, similar to this:
mptcp: remove unused returned value of check_data_fin
Thanks,
-Geliang
>
> Thanks,
> -Geliang
>
> > ---
> > net/mptcp/protocol.c | 5 +----
> > 1 file changed, 1 insertion(+), 4 deletions(-)
> >
> > diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
> > index
> > 1c26acf6c4145896ecbb5c7f7004121c66a20649..f3dda47ad1d70b5c6a326c17d
> > be
> > 6d244c5638ca2 100644
> > --- a/net/mptcp/protocol.c
> > +++ b/net/mptcp/protocol.c
> > @@ -530,11 +530,10 @@ static void mptcp_cleanup_rbuf(struct
> > mptcp_sock *msk, int copied)
> > }
> > }
> >
> > -static bool mptcp_check_data_fin(struct sock *sk)
> > +static void mptcp_check_data_fin(struct sock *sk)
> > {
> > struct mptcp_sock *msk = mptcp_sk(sk);
> > u64 rcv_data_fin_seq;
> > - bool ret = false;
> >
> > /* Need to ack a DATA_FIN received from a peer while this
> > side
> > * of the connection is in ESTABLISHED, FIN_WAIT1, or
> > FIN_WAIT2.
> > @@ -572,12 +571,10 @@ static bool mptcp_check_data_fin(struct sock
> > *sk)
> > break;
> > }
> >
> > - ret = true;
> > if (!__mptcp_check_fallback(msk))
> > mptcp_send_ack(msk);
> > mptcp_close_wake_up(sk);
> > }
> > - return ret;
> > }
> >
> > static void mptcp_dss_corruption(struct mptcp_sock *msk, struct
> > sock
> > *ssk)
> >
> > ---
> > base-commit: e9091ee333eb716a0933dcb08617228dcd3d3623
> > change-id: 20250906-check_data_fin_ret-6d284170880a
> >
> > Best regards,
Hi Geliang,
On 10/09/2025 05:44, Geliang Tang wrote:
> Hi Matt,
>
> On Wed, 2025-09-10 at 11:38 +0800, Geliang Tang wrote:
>> Hi Matt,
>>
>> On Sat, 2025-09-06 at 16:13 +0200, Matthieu Baerts (NGI0) wrote:
>>> When working on a fix modifying mptcp_check_data_fin(), I noticed
>>> the
>>> returned value was no longer used.
>>>
>>> It looks like it was used for 3 days, between commit 7ed90803a213
>>> ("mptcp: send explicit ack on delayed ack_seq incr") and commit
>>> ea4ca586b16f ("mptcp: refine MPTCP-level ack scheduling").
>>>
>>> This returned value can be safely removed.
>>>
>>> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
>>
>> LGTM!
>>
>> Reviewed-by: Geliang Tang <geliang@kernel.org>
>
> Please update the subject when applying this patch, similar to this:
>
> mptcp: remove unused returned value of check_data_fin
Done. Thank you for the review!
Now in our tree:
New patches for t/upstream:
- f99b062ae907: mptcp: remove unused returned value of check_data_fin
- Results: 1e51af26b216..2356642572b2 (export)
Tests are now in progress:
- export:
https://github.com/multipath-tcp/mptcp_net-next/commit/961890711378b6cf214799da98794038222fc86a/checks
Cheers,
Matt
--
Sponsored by the NGI0 Core fund.
Hi Matthieu,
Thank you for your modifications, that's great!
Our CI did some validations and here is its report:
- KVM Validation: normal: Success! ✅
- KVM Validation: debug: Unstable: 1 failed test(s): selftest_mptcp_connect_checksum 🔴
- KVM Validation: btf-normal (only bpftest_all): Success! ✅
- KVM Validation: btf-debug (only bpftest_all): Success! ✅
- Task: https://github.com/multipath-tcp/mptcp_net-next/actions/runs/17515731496
Initiator: Patchew Applier
Commits: https://github.com/multipath-tcp/mptcp_net-next/commits/ffb29b394e92
Patchwork: https://patchwork.kernel.org/project/mptcp/list/?series=999625
If there are some issues, you can reproduce them using the same environment as
the one used by the CI thanks to a docker image, e.g.:
$ cd [kernel source code]
$ docker run -v "${PWD}:${PWD}:rw" -w "${PWD}" --privileged --rm -it \
--pull always mptcp/mptcp-upstream-virtme-docker:latest \
auto-normal
For more details:
https://github.com/multipath-tcp/mptcp-upstream-virtme-docker
Please note that despite all the efforts that have been already done to have a
stable tests suite when executed on a public CI like here, it is possible some
reported issues are not due to your modifications. Still, do not hesitate to
help us improve that ;-)
Cheers,
MPTCP GH Action bot
Bot operated by Matthieu Baerts (NGI0 Core)
© 2016 - 2026 Red Hat, Inc.