commit 3d87c12c0cf345ed6cf776522495d957e8d50f69
Author: Bjorn Helgaas <bjorn.helgaas@hp.com>
Date:   Tue Jul 28 11:06:18 2009 -0600

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd1a6d4..f7c43fb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -166,6 +166,12 @@ and is between 256 and 4096 characters. It is defined in the file
 			(e.g. thinkpad_acpi, sony_acpi, etc.) instead
 			of the ACPI video.ko driver.
 
+	acpi_bind_workqueues [ACPI]
+			Run ACPI workqueues only on CPU 0, to work around
+			BIOS defects.  If this helps, report it with the
+			dmidecode output so future kernels can do it
+			automatically.
+
 	acpi.debug_layer=	[HW,ACPI,ACPI_DEBUG]
 	acpi.debug_level=	[HW,ACPI,ACPI_DEBUG]
 			Format: <int>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 7167071..f4f1295 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -189,6 +189,78 @@ acpi_status __init acpi_os_initialize(void)
 	return AE_OK;
 }
 
+static void bind_to_cpu0(struct work_struct *work)
+{
+	set_cpus_allowed(current, cpumask_of_cpu(0));
+	kfree(work);
+}
+
+static void bind_workqueue(struct workqueue_struct *wq)
+{
+	struct work_struct *work;
+
+	work = kzalloc(sizeof(struct work_struct), GFP_KERNEL);
+	INIT_WORK(work, bind_to_cpu0);
+	queue_work(wq, work);
+}
+
+static int acpi_bind_workqueues;
+static const char *acpi_bind_reason;
+
+static int bind_workqueues_to_0(void)
+{
+	/*
+	 * Some machines seem to have SMI-related state corruption if software
+	 * SMIs are initiated anywhere other than CPU 0.  SMIs could be
+	 * initiated anywhere in AML, but most problem cases seem to be in
+	 * GPE-related AML that's executed via workqueues.
+	 *
+	 * Work around it by binding the ACPI workqueues to CPU 0.
+	 */
+
+	printk(KERN_ERR PREFIX "%s; binding ACPI workqueues to CPU 0\n",
+	       acpi_bind_reason);
+	bind_workqueue(kacpid_wq);
+	bind_workqueue(kacpi_notify_wq);
+	bind_workqueue(kacpi_hotplug_wq);
+	return 0;
+}
+
+static int __init acpi_bind_setup(char *str)
+{
+	acpi_bind_workqueues = 1;
+	acpi_bind_reason = "user request";
+	return 1;
+}
+__setup("acpi_bind_workqueues", acpi_bind_setup);
+
+static int acpi_bind_setup_dmi(const struct dmi_system_id *id)
+{
+	acpi_bind_workqueues = 1;
+	acpi_bind_reason = id->ident;
+	return 0;
+}
+
+static const struct dmi_system_id acpi_cpu0_dmi_table[] = {
+	{
+	.callback = acpi_bind_setup_dmi,
+	.ident = "HP Compaq 2510p notebook",
+	.matches = {
+		    DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		    DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq 2510p"),
+		},
+	},
+	{
+	.callback = acpi_bind_setup_dmi,
+	.ident = "HP Compaq 6910p notebook",
+	.matches = {
+		    DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		    DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq 6910p"),
+		},
+	},
+	{}
+};
+
 acpi_status acpi_os_initialize1(void)
 {
 	kacpid_wq = create_singlethread_workqueue("kacpid");
@@ -197,6 +269,9 @@ acpi_status acpi_os_initialize1(void)
 	BUG_ON(!kacpid_wq);
 	BUG_ON(!kacpi_notify_wq);
 	BUG_ON(!kacpi_hotplug_wq);
+	dmi_check_system(acpi_cpu0_dmi_table);
+	if (acpi_bind_workqueues)
+		bind_workqueues_to_0();
 	return AE_OK;
 }