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 1DFCC52B1FE; Wed, 23 Sep 2026 14:36:44 +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=1790174205; cv=none; b=UJv8f76u+fG+SC/qEUXvo0F4skM86Tfb8B4yOTN010aaT/owarivFwijoLx+77d+2K/cNMTUXB8jZo2NFXGOzQoka/k9L1MobXMpIkpvU4mBXLh0TdE0AJzLWdv2iKIuAuugHF8wtaDx3ksb4LiDVk6YnMq+7FUo2i3ZlLsaNcI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174205; c=relaxed/simple; bh=+JLnRg3TJGSBuViFGHdVmsnrAFkBBwgJmahPtQ0Kc1U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jIsSeTzzjKZxAn2xqTdglQElTANshuh0QxA6g1z+bqh1phupRwXXDpwa/P51yidAujsc5PgSU4QrrxkzXlDoIazL6yLCCI7uzH1e1sB9a8hlqpaEYyrSvuX4tkm4P0ayvSNU1joqlcATw5vD55aBqhjeBLsudpyiviWmloOg2JM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=a11vpW2v; 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="a11vpW2v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E0751F000FF; Wed, 23 Sep 2026 14:36:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790174203; bh=0Bz61IR9PHdOxuwQTqRZhnWCY2ZNqwGHwE0aI6FshUg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=a11vpW2vyx/wvD8Hwrx6GPhX07iVOOfLSO8TGKtXPvSnFPorDT4qKtdu2ifzL9oRX RvGkuOgYmtaHuKyUJVORy8Z1XmybVLGSoJGq+GLYk2OYviC7DXu3oO+/NwBITDZb5X AitxZu9aXqLo1YVQ6TvZwv1AXS8xBv6H9xluv7CM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ovidiu Panait , Geert Uytterhoeven , Sasha Levin Subject: [PATCH 6.18 035/398] arm64: dts: renesas: r9a09g056: Switch GBETH TX queue scheduling to WRR Date: Wed, 23 Sep 2026 16:01:49 +0200 Message-ID: <20260923140644.338405271@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ovidiu Panait [ Upstream commit 66fcbdbeca0118b8aeac218b33fa18c394513543 ] The GBETH ethernet nodes don't specify a TX scheduling policy, so stmmac falls back to Strict Priority. In this configuration the queue with the highest priority gets all the traffic, starving the others under load. Under sustained UDP TX load with multiple data streams, this starvation triggers spurious adapter resets due to TX queue timeouts: iperf3 -c -i0 -t60 --bind-dev end0 -u -b0 -P4 end0: NETDEV WATCHDOG: CPU: 1: transmit queue 1 timed out 5228 ms end0: Reset adapter. Investigation shows that only the highest priority queue is advancing while the others stall for more than 5 seconds, causing a netdev watchdog reset. Switch the TX scheduling policy to Weighted-Round-Robin (WRR) so that traffic is processed across all queues, eliminating the stalls. Fixes: c8c8a57c5b40 ("arm64: dts: renesas: r9a09g056: Add GBETH nodes") Signed-off-by: Ovidiu Panait Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260722085353.136986-3-ovidiu.panait.rb@renesas.com Signed-off-by: Geert Uytterhoeven Signed-off-by: Sasha Levin --- arch/arm64/boot/dts/renesas/r9a09g056.dtsi | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm64/boot/dts/renesas/r9a09g056.dtsi b/arch/arm64/boot/dts/renesas/r9a09g056.dtsi index 8871108789060..cde453fd35e24 100644 --- a/arch/arm64/boot/dts/renesas/r9a09g056.dtsi +++ b/arch/arm64/boot/dts/renesas/r9a09g056.dtsi @@ -827,23 +827,28 @@ queue3 { mtl_tx_setup0: tx-queues-config { snps,tx-queues-to-use = <4>; + snps,tx-sched-wrr; queue0 { + snps,weight = <0x10>; snps,dcb-algorithm; snps,priority = <0x1>; }; queue1 { + snps,weight = <0x12>; snps,dcb-algorithm; snps,priority = <0x2>; }; queue2 { + snps,weight = <0x14>; snps,dcb-algorithm; snps,priority = <0x4>; }; queue3 { + snps,weight = <0x18>; snps,dcb-algorithm; snps,priority = <0x8>; }; @@ -928,23 +933,28 @@ queue3 { mtl_tx_setup1: tx-queues-config { snps,tx-queues-to-use = <4>; + snps,tx-sched-wrr; queue0 { + snps,weight = <0x10>; snps,dcb-algorithm; snps,priority = <0x1>; }; queue1 { + snps,weight = <0x12>; snps,dcb-algorithm; snps,priority = <0x2>; }; queue2 { + snps,weight = <0x14>; snps,dcb-algorithm; snps,priority = <0x4>; }; queue3 { + snps,weight = <0x18>; snps,dcb-algorithm; snps,priority = <0x8>; }; -- 2.53.0