Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966793AbcCPLNY (ORCPT ); Wed, 16 Mar 2016 07:13:24 -0400 Received: from mx2.suse.de ([195.135.220.15]:47250 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966571AbcCPK7y (ORCPT ); Wed, 16 Mar 2016 06:59:54 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Harvey Hunt , Tejun Heo , Jiri Slaby Subject: [PATCH 3.12 18/58] libata: Align ata_device's id on a cacheline Date: Wed, 16 Mar 2016 11:59:03 +0100 Message-Id: <54709aebcea1709772a302a9592d52a8252bc08d.1458125909.git.jslaby@suse.cz> X-Mailer: git-send-email 2.7.3 In-Reply-To: <377b71e18f20d69b0df301ce7040554f40ba9651.1458125909.git.jslaby@suse.cz> References: <377b71e18f20d69b0df301ce7040554f40ba9651.1458125909.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1354 Lines: 41 From: Harvey Hunt 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 4ee34ea3a12396f35b26d90a094c75db95080baa upstream. The id buffer in ata_device is a DMA target, but it isn't explicitly cacheline aligned. Due to this, adjacent fields can be overwritten with stale data from memory on non coherent architectures. As a result, the kernel is sometimes unable to communicate with an ATA device. Fix this by ensuring that the id buffer is cacheline aligned. This issue is similar to that fixed by Commit 84bda12af31f ("libata: align ap->sector_buf"). Signed-off-by: Harvey Hunt Cc: linux-kernel@vger.kernel.org Signed-off-by: Tejun Heo Signed-off-by: Jiri Slaby --- include/linux/libata.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/libata.h b/include/linux/libata.h index 189c9ff97b29..a445209be917 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -712,7 +712,7 @@ struct ata_device { union { u16 id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */ u32 gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */ - }; + } ____cacheline_aligned; /* DEVSLP Timing Variables from Identify Device Data Log */ u8 devslp_timing[ATA_LOG_DEVSLP_SIZE]; -- 2.7.3