From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25952C4CEC4 for ; Wed, 18 Sep 2019 06:32:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6A7C21906 for ; Wed, 18 Sep 2019 06:32:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568788329; bh=xCYf6H3BZ4UqZg17dDZOqY8hskqn5G7eCavzPOr6A7A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=L4zrTfrf5lniQy5Li1dYnOMtXtRuvubSO7sEfcB7b+Wa7pK9wJH+hDz/Gxh82PTjz eew5NIwkq6tvf6y4fEvIVcpSL5mLtx7uyrUkvCQ3PRybSJm9Z2zmYtUEseLqoybT5z 64hzN+UuE86PBVB/qHcxUyzpEknuNGfvJi8UA3R4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728436AbfIRGWa (ORCPT ); Wed, 18 Sep 2019 02:22:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:42404 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726038AbfIRGW1 (ORCPT ); Wed, 18 Sep 2019 02:22:27 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6E95B218AE; Wed, 18 Sep 2019 06:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568787746; bh=xCYf6H3BZ4UqZg17dDZOqY8hskqn5G7eCavzPOr6A7A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PtJ5uvn5Saig9S2MPc411/6Nl2sxa4DfRPHUlcyHVGvxwKO8RaNA5aalPY2n5eXrZ Vki0DD8XPk82XpFrGPBFojYw2k7L5nsUmg/MntkNKOMLpkFFSZ5tW3feCkPQJ9hGQ1 nuKc9Gc/axWzXx3gPPOTD7k4QrM+JwibJOdwhmPg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gregg Leventhal , Alexander Duyck , Andrew Bowers , Jeff Kirsher Subject: [PATCH 4.19 19/50] ixgbe: Prevent u8 wrapping of ITR value to something less than 10us Date: Wed, 18 Sep 2019 08:19:02 +0200 Message-Id: <20190918061225.140090286@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190918061223.116178343@linuxfoundation.org> References: <20190918061223.116178343@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexander Duyck commit 377228accbbb8b9738f615d791aa803f41c067e0 upstream. There were a couple cases where the ITR value generated via the adaptive ITR scheme could exceed 126. This resulted in the value becoming either 0 or something less than 10. Switching back and forth between a value less than 10 and a value greater than 10 can cause issues as certain hardware features such as RSC to not function well when the ITR value has dropped that low. CC: stable@vger.kernel.org Fixes: b4ded8327fea ("ixgbe: Update adaptive ITR algorithm") Reported-by: Gregg Leventhal Signed-off-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -2626,7 +2626,7 @@ adjust_by_size: /* 16K ints/sec to 9.2K ints/sec */ avg_wire_size *= 15; avg_wire_size += 11452; - } else if (avg_wire_size <= 1980) { + } else if (avg_wire_size < 1968) { /* 9.2K ints/sec to 8K ints/sec */ avg_wire_size *= 5; avg_wire_size += 22420; @@ -2659,6 +2659,8 @@ adjust_by_size: case IXGBE_LINK_SPEED_2_5GB_FULL: case IXGBE_LINK_SPEED_1GB_FULL: case IXGBE_LINK_SPEED_10_FULL: + if (avg_wire_size > 8064) + avg_wire_size = 8064; itr += DIV_ROUND_UP(avg_wire_size, IXGBE_ITR_ADAPTIVE_MIN_INC * 64) * IXGBE_ITR_ADAPTIVE_MIN_INC;