From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1468877-1518324813-2-15361442336480358676 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518324813; b=bDph8jLzRXSyT7uTuH0EvjDPVXzWlIswHAv+VAx83Tiw8aO 8JeahUigHVFPaBlF1Kj67kC6du52MRMLq8dDWyhkWbx8sy4DrywausTyCeVZ29On uiuZxub9JreXXHk1ioW3EIT71LsfDJE7l9pqnzZNzfFzhKRAqYny3e/Foq31/edx t/FbLGOu5Zdas4elnh8LP1EHmGR6HlptY+MeXVHblzknCsFg3VR6h6kC81hoOOdg TYAiD21AfeicMV8i4XREusbIg6nF4tR8KBP5YAWFrjDmzGrgmlS3NJjDFk8/cjOV KNbxfhq8Bou3pAHSlpefiMA19nuW2JOxQE1BNEA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1518324813; bh=WIn1YKftudxJtRZa0a5 UadJITcr4CgRbEjmXfvzBD7c=; b=nLcnwmRtn0aWoR2V40MKlJ8W+WALblE190u GxObaiO5pHet+ELUhuBt85BpH2teyRZzpBlQLC5mPyb5P0Hts7Yv3TOYSjAR4o6N zjRFOYLsAYyI3n+SciRC+/WhArJEcttIUj5/Wtp4q9afHQCIjSUsjPr0yWls698H ytcAZ/suy2TtBG3VLq0FEmheo4HDq0Z4418enlrzWkGTF9r4w66hdObJbwHdLMIn lzWBWnccu+/LUOFX97x0EUHifvbxnG0AsQYA8evi7Rz8WJuc82RAmU5mraGjCOp/ cNTSNrtXG7+PIKVYS56LFYAEPSj5PRLx4OqSTzlScchIZoRSprg== ARC-Authentication-Results: i=1; mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753167AbeBKEvm (ORCPT ); Sat, 10 Feb 2018 23:51:42 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41750 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752815AbeBKEd5 (ORCPT ); Sat, 10 Feb 2018 23:33:57 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jeff Kirsher" , "Jesse Brandeburg" , "Brian King" , "Andrew Bowers" Date: Sun, 11 Feb 2018 04:31:11 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 113/136] i40evf: Use smp_rmb rather than read_barrier_depends In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.54-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Brian King commit f72271e2a0ae4277d53c4053f5eed8bb346ba38a upstream. The original issue being fixed in this patch was seen with the ixgbe driver, but the same issue exists with i40evf as well, as the code is very similar. read_barrier_depends is not sufficient to ensure loads following it are not speculatively loaded out of order by the CPU, which can result in stale data being loaded, causing potential system crashes. Signed-off-by: Brian King Acked-by: Jesse Brandeburg Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Ben Hutchings --- drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -216,7 +216,7 @@ static bool i40e_clean_tx_irq(struct i40 break; /* prevent any other reads prior to eop_desc */ - read_barrier_depends(); + smp_rmb(); /* we have caught up to head, no work left to do */ if (tx_head == tx_desc)