From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063137; b=GBA728RZJkuvxsuISyvO1Wf/88NMXxuA0nVe/AzeXhg88SWlNe68vCmxbvi56vWBwAcp 9Su1v2tFezPLRL/oMzAqxTqBD/evY0feYFHh+VXmhRGGg3hKwAhrlptAv/Mz9q/Ob2bxB BMXJlpQq2A6LYhog+jsV7/2zvnjwqvHM+jp69Lg54HihaO7DpgOBoshGjpbE6Kku9JgPe X8KVOt0N4oqjIdG3mBlcib7s2oWl3acWnMbTzezM5SalqAsPfhNIXeBgikNJqAEv1Gj/S xsvIcLGv4t0SugGZJ22vjIScf6EiHuWNa+EvGCVLdeZZvkMEK+JMEJqQNSnGddTZZTg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063137; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=pc9IRZ54AUeKErUXvyrvvVsxNeINTUz+TKZPyrQ1Bn8=; b=rE/kiLuWR5UVsIaoyaOslNgRiVwrSTVS+o9UsCG9NA3fY6gsxjL5aJPS1F8pKKnfomkU WkfnFOHver/+huY0FIz9MBum9d9Of7axdOWAk0CtzpQ/e9z1DH8gb3AZ0bJiUaThcL1Tv QEm/UkS8EqNbyXNzsoCuSLtDztg7KvEAvf5O9pATn6E2zRtYue/dyCp0HykUkdWGc7bUx nUKEZMm3Gr6rrqDgY0rP1mupSBe3/jJgUvo+5S8QzUm56E9D/Yxk6vZdSCtln2qMqXHv9 wuFhfPc2Ip4pwe475DIvW6xR4l3sqK+pRbrOel9dcSdzRgL2KMMHIQadb3o9G18E1qQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=SO3B5Gdv; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9D9E9606D814; Sat, 7 Nov 2026 14:52:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=SO3B5Gdv Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D7EE1F008A1; Sat, 7 Nov 2026 14:52:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063137; bh=pc9IRZ54AUeKErUXvyrvvVsxNeINTUz+TKZPyrQ1Bn8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SO3B5Gdv/+3LGwEMkE/J/zWEwlp+bSEQs2OgoADjVBzpZnf7HSEdkOvA5IOVrPeZo NT+VbYxxZC1A4XUZUxquOzPDRnzL0nIck5319yuDqX7SsJLFnuAd5soprEYazjUxXC sCRF9vEzU945VTDaIqcf15JMmtwu5HC1wt8BFHME= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chuck Lever , Sasha Levin Subject: [PATCH 6.18 366/869] svcrdma: Grant credits from the clamped sc_max_requests Date: Sat, 7 Nov 2026 08:50:48 -0500 Message-ID: <20261107134905.122634092@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever [ Upstream commit b7037e5da3fb81abcd6309daecb112f1d5926760 ] svc_rdma_accept() computes sc_fc_credits from sc_max_requests before the Receive Queue depth is checked against the device's max_qp_wr. When that check lowers sc_max_requests, the credit grant keeps the original value, so the server advertises more credits than it has Receives posted. A client that uses the full grant overruns the Receive Queue, and the connection is lost with an RNR error. Set sc_fc_credits after the clamp so the grant matches the number of Receives the server posts. Fixes: fc2e69db82c1 ("svcrdma: Clean up comment in svc_rdma_accept()") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260828135036.796842-2-cel@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- net/sunrpc/xprtrdma/svc_rdma_transport.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 4afa662430cae..d9bc86fa09bce 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -469,7 +469,6 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_max_requests = svcrdma_max_requests; newxprt->sc_max_bc_requests = svcrdma_max_bc_requests; newxprt->sc_recv_batch = RPCRDMA_MAX_RECV_BATCH; - newxprt->sc_fc_credits = cpu_to_be32(newxprt->sc_max_requests); /* Qualify the transport's resource defaults with the * capabilities of this particular device. @@ -490,6 +489,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_max_bc_requests = 2; } + newxprt->sc_fc_credits = cpu_to_be32(newxprt->sc_max_requests); + /* Estimate the needed number of rdma_rw contexts. The maximum * Read and Write chunks have one segment each. Each request * can involve one Read chunk and either a Write chunk or Reply -- 2.53.0