From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Soltys Subject: question: tg3 driver/nics and inconsistent RX ring count Date: Tue, 26 Jul 2016 21:52:50 +0200 Message-ID: <01ffefd8-8191-b423-0ccf-feb2d769d8d2@ziu.info> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: Linux Netdev List Return-path: Received: from drutsystem.com ([84.10.39.251]:36355 "EHLO drutsystem.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757532AbcGZTxB (ORCPT ); Tue, 26 Jul 2016 15:53:01 -0400 Received: from [10.0.0.2] (89-65-85-89.dynamic.chello.pl [89.65.85.89]) (Authenticated sender: nozo) by drutsystem.com (Postfix) with ESMTPA id C15F49371F for ; Tue, 26 Jul 2016 21:52:50 +0200 (CEST) Sender: netdev-owner@vger.kernel.org List-ID: Hi, I have a few of BCM5720 and BCM5719 kinds sitting in Dell R320 and R520 servers - and all of them have certain peculiarity: they claim to have up to 4 TX and RX rings (and this can be set/verified just fine through ethtool -l/-L, with driver defaulting to 4 rings), indirection table (ethtool -x) looks fine as well: RX flow hash indirection table for eth1b with 3 RX ring(s): 0: 0 1 2 3 0 1 2 3 8: 0 1 2 3 0 1 2 3 ...... But this "3 RX ring(s)" is actually a real limit if I try to adjust anything, for example all those commands would fail: ethtool -X eth1b equal 4 ethtool -X eth1b weight 1 1 1 1 But would work fine for 3 and less rings. This was quickly tested with different kernel/ethtool combinations, from old 3.16 to 4.6.y with same exact results. Nothing fancier (-N/-U) is supported either. Any hints/comments about the cause of this and/or possible workarounds ?