From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BF31413D521 for ; Sat, 15 Nov 2025 01:32:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763170328; cv=none; b=I+mts4S2zm7AgQvxJUKNeln5D//JI5Y/AXd3DulGWtTon1B2C9aC9na3MONUtkguv81XkWobxU/ZtVRaU4OG7WChBKXO7w18gcXPMn9AA84OZH9vbMDDuF1jW0O+ZOs7gAeGytUlZbaevVJT83Zorx1gs8JhvG285jgmbEGEe64= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763170328; c=relaxed/simple; bh=hBR7fB7xrRfooGi2N8U9sx8z03rz2u0IlQh2QO2Iv8A=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=MBt4JQeT4dAwJeZTauMhrjdjRtN3Fr9jAYEAei3jw3nyl3Grtoi020Su9GpNtcMZv3uKUIHr8cDK1u9ZAmVYkLoQYABD+E9x/Bowd8AHNO8MdT2zyN2gNW5AX3Py1V72DllcRAPN2sNxV5YEE3OYjATUC4Lh13dxNmFjdJkNnpA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=evpkeIMS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="evpkeIMS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32A49C4CEF8; Sat, 15 Nov 2025 01:32:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763170327; bh=hBR7fB7xrRfooGi2N8U9sx8z03rz2u0IlQh2QO2Iv8A=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=evpkeIMSFY76Idk0vH33H/LJg6Ox19SVfoZQKConqj9xiHbYDxP8BIJ4vdB5KPH94 jjMMXagejeVynsOKLgcxPIE9g7lyc0XcuaRF3WkCVwivMM14DsExL2tXvQDYWAF+4K aRZFN1XWhWf1SI7L4UUj4TWddQV2hFWlmgkDkLJDFL58TMbJbQ9BbpaQxWbv2sY6hB T5yfxpdK73ydpLS3QCJ5Qmo0KjMSd6AqbVpPGpN4qN6E4awBVSpHQZKjCTn2FMjxu1 DBlWb1BDQrB+QrWiZ/WDpmaEZNQJO5boofVNzvWO0JTaBPO6/QWVdmpTFcA17GGAA+ m5hQf7fDj6xkQ== Date: Fri, 14 Nov 2025 17:32:06 -0800 (PST) From: Mat Martineau To: Paolo Abeni cc: mptcp@lists.linux.dev Subject: Re: [PATCH v4 mptcp-next 2/6] mptcp: fix receive space timestamp initialization. In-Reply-To: <7152b5431a95b1b52251e7df3120590c28749a1a.1762940290.git.pabeni@redhat.com> Message-ID: <60fc0dfb-df45-f57b-7a9c-02cb8271adbd@kernel.org> References: <7152b5431a95b1b52251e7df3120590c28749a1a.1762940290.git.pabeni@redhat.com> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed On Wed, 12 Nov 2025, Paolo Abeni wrote: > MPTCP initialize the receive buffer stamp in mptcp_rcv_space_init(), > using the provided subflow stamp. Such helper is invoked in several > places; for passive sockets, space init happened at clone time. > > In such scenario, MPTCP ends-up accesses the subflow stamp before > its initialization, leading to quite randomic timing for the first > receive buffer auto-tune event, as the timestamp for newly created > subflow is not refreshed there. > > Fix the issue moving the stamp initialization of the mentioned helper, as > soon at the data transfer start, and always using a fresh timestamp. > > This will also make the next patch cleaner. > > Fixes: 013e3179dbd2 ("mptcp: fix rcv space initialization") > Signed-off-by: Paolo Abeni > --- > v1 -> v2: > -- factor out only the tstamp change for better reviewability > --- > net/mptcp/protocol.c | 7 ++++--- > net/mptcp/protocol.h | 5 +++++ > 2 files changed, 9 insertions(+), 3 deletions(-) Reviewed-by: Mat Martineau