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=ham 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 E0AEAC4CED0 for ; Wed, 18 Sep 2019 06:27:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B88FC21924 for ; Wed, 18 Sep 2019 06:27:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568788071; bh=CapMQcwz8Xsl+NfwobmOyBqf7rfL3JT1Ov3A4rA6++E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gzgdrJ0gHzJ8gApxpMLbWuSC9O2mkDF+VQOB0jD2T8qeHQoMScqGq5iRw4uX+OnZp Jl791ePEs6Oze6jL6Jz2NEQR33B3RNOOMttx1IGt8vqLszY+oxUqaQm27zcfV24z+y qCKeIFyAwBugVB0bEd9qI0hecUAoiNXiI41atPGg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730601AbfIRG1u (ORCPT ); Wed, 18 Sep 2019 02:27:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:49892 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729777AbfIRG1u (ORCPT ); Wed, 18 Sep 2019 02:27:50 -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 5C6D721924; Wed, 18 Sep 2019 06:27:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568788069; bh=CapMQcwz8Xsl+NfwobmOyBqf7rfL3JT1Ov3A4rA6++E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X5QvFyFBDWOhTxtIFcdPuiUI3Qd1TJ2fsg7jH49Ir3UqYBO19E364GYL+Oa5zoBhn ueCyzehsRvM1sf2Yjbxg6fb3Fa2iaGBgKwNe0wCamtjVfMxuzG/+8hiX2nJNPzwFMm NH40EfiX7c3iI6P8R+SHClLuhzaS6zkQTbyDEP0g= 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 5.2 38/85] ixgbe: Prevent u8 wrapping of ITR value to something less than 10us Date: Wed, 18 Sep 2019 08:18:56 +0200 Message-Id: <20190918061235.347046644@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190918061234.107708857@linuxfoundation.org> References: <20190918061234.107708857@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 @@ -2622,7 +2622,7 @@ 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; @@ -2655,6 +2655,8 @@ 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;