From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 80D8344239B; Fri, 7 Aug 2026 14:57:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114632; cv=none; b=Yy09ttmDVCIi6cFhu7vXnDlWRW1tE1Grxp8dvHj1ZglZnIoltMrhpEaDnvyoZUaTsseVReO5S/adApQgVtb5uqrd3uu4Q9lL7NXoJ3Qn9bKu61Rt0K8Ez4VIhWWvJCXHRNxiLCcJAyDMsrho2WYck8VQwzSb1pN1qXKHeMA1VaA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114632; c=relaxed/simple; bh=rsOnejBQSdGH5fsuyA1V2rPZ6pYsyNHKlh/rzjne/AQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eW0cAmUBd9VMMSW1icBskC+SXHh3h2+koICzeQeNGY/0uXa/70uJXis2QQLyd/sfDSqMapuRAE5Zuk8KJdDmjOV5HkFMYbBpZuyqFQ0RST57D0Gbl0CgV1QH99/s7f94EMwQaektOjvM+qbhA3dYJm188c2AaFgtMe4/gMUqCPo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0y4PzOc4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="0y4PzOc4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C72B1F00A3A; Fri, 7 Aug 2026 14:57:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786114625; bh=XwDGOubuX4Sf6tbLSEt9Kv97cV//AUsxjU8PCJOSL44=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=0y4PzOc4LmCdf2Tsn89Hkuw4XquhkiJMEndZXxQ+m4du52NEKN3UGRWdAqyIaH9/i Q1RsWZRtyJC7p8Xnzcf3OoperTstDhndC2ZmtUwThX2goZmIYNy8VC3+ntCCj/utLk 9giQiVo0aLEwMFrjI+4FOtMkRxwO8cRdtJqC/8ZU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Howells , Simon Wilkinson , Marc Dionne , linux-afs@lists.infradead.org, Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 330/337] rxrpc: Fix the calculation and use of RTO Date: Fri, 7 Aug 2026 16:38:53 +0200 Message-ID: <20260807143425.695475885@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143418.516897842@linuxfoundation.org> References: <20260807143418.516897842@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Howells [ Upstream commit 5c0ceba23bb47085d6c9c53bff08a29634ee4e7e ] Make the following changes to the calculation and use of RTO: (1) Fix rxrpc_resend() to use the backed-off RTO value obtained by calling rxrpc_get_rto_backoff() rather than extracting the value itself. Without this, it may retransmit packets too early. (2) The RTO value being similar to the RTT causes a lot of extraneous resends because the RTT doesn't end up taking account of clearing out of the receive queue on the server. Worse, responses to PING-ACKs are made as fast as possible and so are less than the DATA-requested-ACK RTT and so skew the RTT down. Fix this by putting a lower bound on the RTO by adding 100ms to it and limiting the lower end to 200ms. Fixes: c410bf01933e ("rxrpc: Fix the excessive initial retransmission timeout") Fixes: 37473e416234 ("rxrpc: Clean up the resend algorithm") Signed-off-by: David Howells Suggested-by: Simon Wilkinson cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Jakub Kicinski Stable-dep-of: e4d2878369d5 ("rxrpc: Fix irq-disabled in local_bh_enable()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/rxrpc/call_event.c | 3 ++- net/rxrpc/rtt.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -71,7 +71,8 @@ void rxrpc_resend(struct rxrpc_call *cal struct rxrpc_skb_priv *sp; struct rxrpc_txbuf *txb; rxrpc_seq_t transmitted = call->tx_transmitted; - ktime_t next_resend = KTIME_MAX, rto = ns_to_ktime(call->peer->rto_us * NSEC_PER_USEC); + ktime_t next_resend = KTIME_MAX; + ktime_t rto = rxrpc_get_rto_backoff(call->peer, false); ktime_t resend_at = KTIME_MAX, now, delay; bool unacked = false, did_send = false; unsigned int i; --- a/net/rxrpc/rtt.c +++ b/net/rxrpc/rtt.c @@ -27,7 +27,7 @@ static u32 __rxrpc_set_rto(const struct static u32 rxrpc_bound_rto(u32 rto) { - return min(rto, RXRPC_RTO_MAX); + return clamp(200000, rto + 100000, RXRPC_RTO_MAX); } /*