ACPI / sleep: Drain outstanding events after disabling multiple GPEs

rafaeljw · rafaeljw · commit c52fa70c79ac · 2014-12-01T23:51:13.000+01:00
After multiple GPEs have been disabled at the low level in one go,
like when acpi_disable_all_gpes() is called, we should always drain
all of the outstanding events from them, or interesting races become
possible.

For this reason, call acpi_os_wait_events_complete() after
acpi_enable_all_wakeup_gpes() and acpi_disable_all_gpes() in
acpi_freeze_prepare() and acpi_power_off_prepare(), respectively.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
@@ -630,6 +630,7 @@ static int acpi_freeze_begin(void)
 static int acpi_freeze_prepare(void)
 {
 	acpi_enable_all_wakeup_gpes();
+	acpi_os_wait_events_complete();
 	enable_irq_wake(acpi_gbl_FADT.sci_interrupt);
 	return 0;
 }
@@ -825,6 +826,7 @@ static void acpi_power_off_prepare(void)
 	/* Prepare to power off the system */
 	acpi_sleep_prepare(ACPI_STATE_S5);
 	acpi_disable_all_gpes();
+	acpi_os_wait_events_complete();
 }
 
 static void acpi_power_off(void)

Original file line number	Diff line number	Diff line change
`@@ -630,6 +630,7 @@ static int acpi_freeze_begin(void)`
`630`	`630`	`static int acpi_freeze_prepare(void)`
`631`	`631`	`{`
`632`	`632`	`acpi_enable_all_wakeup_gpes();`
	`633`	`+ acpi_os_wait_events_complete();`
`633`	`634`	`enable_irq_wake(acpi_gbl_FADT.sci_interrupt);`
`634`	`635`	`return 0;`
`635`	`636`	`}`
`@@ -825,6 +826,7 @@ static void acpi_power_off_prepare(void)`
`825`	`826`	`/* Prepare to power off the system */`
`826`	`827`	`acpi_sleep_prepare(ACPI_STATE_S5);`
`827`	`828`	`acpi_disable_all_gpes();`
	`829`	`+ acpi_os_wait_events_complete();`
`828`	`830`	`}`
`829`	`831`
`830`	`832`	`static void acpi_power_off(void)`