ACPI / PM: Hold acpi_scan_lock over system PM transitions

Bad things happen if ACPI hotplug events are handled during system
PM transitions, especially if devices are removed as a result.
To prevent those bad things from happening, acquire acpi_scan_lock
when a PM transition is started and release it when that transition
is complete or has been aborted.

This fixes resume lockup on my test-bed Acer Aspire S5 that happens
when Thunderbolt devices are disconnected from the machine while
suspended.

Also fixes the analogous problem for Mika Westerberg on an
Intel DZ77RE-75K board.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
This commit is contained in:
Rafael J. Wysocki 2013-08-20 01:42:32 +02:00
parent 1aaac07112
commit ad07277e82

View File

@ -420,10 +420,21 @@ static void acpi_pm_finish(void)
}
/**
* acpi_pm_end - Finish up suspend sequence.
* acpi_pm_start - Start system PM transition.
*/
static void acpi_pm_start(u32 acpi_state)
{
acpi_target_sleep_state = acpi_state;
acpi_sleep_tts_switch(acpi_target_sleep_state);
acpi_scan_lock_acquire();
}
/**
* acpi_pm_end - Finish up system PM transition.
*/
static void acpi_pm_end(void)
{
acpi_scan_lock_release();
/*
* This is necessary in case acpi_pm_finish() is not called during a
* failing transition to a sleep state.
@ -451,21 +462,19 @@ static u32 acpi_suspend_states[] = {
static int acpi_suspend_begin(suspend_state_t pm_state)
{
u32 acpi_state = acpi_suspend_states[pm_state];
int error = 0;
int error;
error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
if (error)
return error;
if (sleep_states[acpi_state]) {
acpi_target_sleep_state = acpi_state;
acpi_sleep_tts_switch(acpi_target_sleep_state);
} else {
printk(KERN_ERR "ACPI does not support this state: %d\n",
pm_state);
error = -ENOSYS;
if (!sleep_states[acpi_state]) {
pr_err("ACPI does not support sleep state S%u\n", acpi_state);
return -ENOSYS;
}
return error;
acpi_pm_start(acpi_state);
return 0;
}
/**
@ -631,10 +640,8 @@ static int acpi_hibernation_begin(void)
int error;
error = nvs_nosave ? 0 : suspend_nvs_alloc();
if (!error) {
acpi_target_sleep_state = ACPI_STATE_S4;
acpi_sleep_tts_switch(acpi_target_sleep_state);
}
if (!error)
acpi_pm_start(ACPI_STATE_S4);
return error;
}
@ -713,8 +720,10 @@ static int acpi_hibernation_begin_old(void)
if (!error) {
if (!nvs_nosave)
error = suspend_nvs_alloc();
if (!error)
if (!error) {
acpi_target_sleep_state = ACPI_STATE_S4;
acpi_scan_lock_acquire();
}
}
return error;
}