6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Paolo Abeni pabeni@redhat.com
commit b111d8fbd2cbc63e05f3adfbbe0d4df655dfcc5b upstream.
After the blamed commit below, the send buffer auto-tuning can happen after that the mptcp_propagate_sndbuf() completes - via the delegated action infrastructure.
We must check for write space even after such change or we risk missing the wake-up event.
Fixes: 8005184fd1ca ("mptcp: refactor sndbuf auto-tuning") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni pabeni@redhat.com Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-6-162... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/protocol.h | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-)
--- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -772,6 +772,16 @@ static inline bool mptcp_data_fin_enable READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); }
+static inline void mptcp_write_space(struct sock *sk) +{ + if (sk_stream_is_writeable(sk)) { + /* pairs with memory barrier in mptcp_poll */ + smp_mb(); + if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) + sk_stream_write_space(sk); + } +} + static inline void __mptcp_sync_sndbuf(struct sock *sk) { struct mptcp_subflow_context *subflow; @@ -790,6 +800,7 @@ static inline void __mptcp_sync_sndbuf(s
/* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); + mptcp_write_space(sk); }
/* The called held both the msk socket and the subflow socket locks, @@ -820,16 +831,6 @@ static inline void mptcp_propagate_sndbu local_bh_enable(); }
-static inline void mptcp_write_space(struct sock *sk) -{ - if (sk_stream_is_writeable(sk)) { - /* pairs with memory barrier in mptcp_poll */ - smp_mb(); - if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) - sk_stream_write_space(sk); - } -} - void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags);
#define MPTCP_TOKEN_MAX_RETRIES 4