linux-kernel - [PATCH 3/3] PCI Hotplug: workaround for Thunderbolt on Intel DZ77RE-75K motherboard

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1355412708-20046-4-git-send-email-kirill.shutemov@linux.intel.com>
Date:	Thu, 13 Dec 2012 17:31:48 +0200
From:	"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To:	Greg KH <gregkh@...uxfoundation.org>
Cc:	Miles J Penner <miles.j.penner@...el.com>,
	John Ronciak <john.ronciak@...el.com>,
	Mika Westerberg <mika.westerberg@...ux.intel.com>,
	Tushar N Dave <tushar.n.dave@...el.com>,
	"Kirill A. Shutemov" <kirill@...temov.name>,
	"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Yinghai Lu <yinghai@...nel.org>,
	Jesse Barnes <jbarnes@...tuousgeek.org>,
	Amos Kong <kongjianjun@...il.com>,
	"Rafael J. Wysocki" <rjw@...k.pl>, linux-pci@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 3/3] PCI Hotplug: workaround for Thunderbolt on Intel DZ77RE-75K motherboard

From: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>

BIOS on Intel DZ77RE-75K motherboard notifies OS about Thunderbolt
hotplug before devices behind Thunderbolt are ready to be enumerated.

Let's delay enumeration by 2 seconds.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
---
 drivers/pci/hotplug/acpiphp_glue.c |   16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 1a2b3ca..165987a 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -49,6 +49,7 @@
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 
 #include "../pci.h"
 #include "acpiphp.h"
@@ -1327,6 +1328,19 @@ out:
 static void handle_hotplug_event_bridge(acpi_handle handle, u32 type,
 					void *context)
 {
+	unsigned long delay = 0;
+	const char *board_name;
+
+	board_name = dmi_get_system_info(DMI_BOARD_NAME);
+	/*
+	 * BIOS on Intel DZ77RE-75K motherboard notifies OS about Thunderbolt
+	 * hotplug before devices behind Thunderbolt are ready to be
+	 * enumerated.
+	 * Let's delay enumeration by 2 seconds.
+	 */
+	if (board_name && !strcmp(board_name, "DZ77RE-75K"))
+		delay = 2 * HZ;
+
 	/*
 	 * Currently the code adds all hotplug events to the kacpid_wq
 	 * queue when it should add hotplug events to the kacpi_hotplug_wq.
@@ -1336,7 +1350,7 @@ static void handle_hotplug_event_bridge(acpi_handle handle, u32 type,
 	 * don't deadlock on hotplug actions.
 	 */
 	alloc_acpiphp_hp_work(handle, type, context,
-			      _handle_hotplug_event_bridge, 0);
+			      _handle_hotplug_event_bridge, delay);
 }
 
 static void _handle_hotplug_event_func(struct work_struct *work)
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/