Skip to content

Commit

Permalink
ACPI: bind workqueues to CPU 0 to avoid SMI corruption
Browse files Browse the repository at this point in the history
On some machines, a software-initiated SMI causes corruption unless the
SMI runs on CPU 0.  An SMI can be initiated by any AML, but typically it's
done in GPE-related methods that are run via workqueues, so we can avoid
the known corruption cases by binding the workqueues to CPU 0.

References:
    http://bugzilla.kernel.org/show_bug.cgi?id=13751
    https://bugs.launchpad.net/bugs/157171
    https://bugs.launchpad.net/bugs/157691

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
  • Loading branch information
Bjorn Helgaas authored and Len Brown committed Aug 2, 2009
1 parent ed680c4 commit 74b5820
Showing 1 changed file with 25 additions and 0 deletions.
25 changes: 25 additions & 0 deletions drivers/acpi/osl.c
Original file line number Diff line number Diff line change
Expand Up @@ -189,11 +189,36 @@ 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);
}

acpi_status acpi_os_initialize1(void)
{
/*
* On some machines, a software-initiated SMI causes corruption unless
* the SMI runs on CPU 0. An SMI can be initiated by any AML, but
* typically it's done in GPE-related methods that are run via
* workqueues, so we can avoid the known corruption cases by binding
* the workqueues to CPU 0.
*/
kacpid_wq = create_singlethread_workqueue("kacpid");
bind_workqueue(kacpid_wq);
kacpi_notify_wq = create_singlethread_workqueue("kacpi_notify");
bind_workqueue(kacpi_notify_wq);
kacpi_hotplug_wq = create_singlethread_workqueue("kacpi_hotplug");
bind_workqueue(kacpi_hotplug_wq);
BUG_ON(!kacpid_wq);
BUG_ON(!kacpi_notify_wq);
BUG_ON(!kacpi_hotplug_wq);
Expand Down

0 comments on commit 74b5820

Please sign in to comment.