From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756174Ab2HFMYK (ORCPT ); Mon, 6 Aug 2012 08:24:10 -0400 Received: from mga02.intel.com ([134.134.136.20]:40704 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756055Ab2HFMYH (ORCPT ); Mon, 6 Aug 2012 08:24:07 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,351,1309762800"; d="scan'208";a="182172459" From: Tomas Winkler To: gregkh@linuxfoundation.org Cc: arnd@arndb.de, alan@linux.intel.com, linux-kernel@vger.kernel.org, Tomas Winkler Subject: [char-misc 3.6] mei: add mei_quirk_probe function Date: Mon, 6 Aug 2012 15:23:55 +0300 Message-Id: <1344255835-11139-1-git-send-email-tomas.winkler@intel.com> X-Mailer: git-send-email 1.7.4.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The main purpose of this function is to exclude ME devices without support for MEI/HECI interface from binding Currently affected systems are C600/X79 based servers that expose PCI device even though it doesn't supported ME Interface. MEI driver accessing such nonfunctional device can corrupt the system. Signed-off-by: Tomas Winkler --- drivers/misc/mei/main.c | 27 +++++++++++++++++++++++++++ 1 files changed, 27 insertions(+), 0 deletions(-) diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c index 0923302..7422c76 100644 --- a/drivers/misc/mei/main.c +++ b/drivers/misc/mei/main.c @@ -925,6 +925,27 @@ static struct miscdevice mei_misc_device = { }; /** + * mei_quirk_probe - probe for devices that doesn't valid ME interface + * @pdev: PCI device structure + * @ent: entry into pci_device_table + * + * returns true if ME Interface is valid, false otherwise + */ +static bool __devinit mei_quirk_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + u32 reg; + if (ent->device == MEI_DEV_ID_PBG_1) { + pci_read_config_dword(pdev, 0x48, ®); + /* make sure that bit 9 is up and bit 10 is down */ + if ((reg & 0x600) == 0x200) { + dev_info(&pdev->dev, "Device doesn't have valid ME Interface\n"); + return false; + } + } + return true; +} +/** * mei_probe - Device Initialization Routine * * @pdev: PCI device structure @@ -939,6 +960,12 @@ static int __devinit mei_probe(struct pci_dev *pdev, int err; mutex_lock(&mei_mutex); + + if (!mei_quirk_probe(pdev, ent)) { + err = -ENODEV; + goto end; + } + if (mei_device) { err = -EEXIST; goto end; -- 1.7.4.4