Commit c7e0831d authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Linus Torvalds
Browse files

Hibernation: Check if ACPI is enabled during restore in the right place



The following scenario leads to total confusion of the platform firmware on
some boxes (eg. HPC nx6325):
* Hibernate with ACPI enabled
* Resume passing "acpi=off" to the boot kernel

To prevent this from happening it's necessary to check if ACPI is enabled (and
enable it if that's not the case) _right_ _after_ control has been transfered
from the boot kernel to the image kernel, before device_power_up() is called
(ie.  with interrupts disabled).   Enabling ACPI after calling
device_power_up() turns out to be insufficient.

For this reason, introduce new hibernation callback ->leave() that will be
executed before device_power_up() by the restored image kernel.   To make it
work, it also is necessary to move swsusp_suspend() from swsusp.c to disk.c
(it's name is changed to "create_image", which is more up to the point).
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent efa4d2fb
......@@ -257,6 +257,15 @@ static int acpi_hibernation_enter(void)
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
static void acpi_hibernation_leave(void)
{
/*
* If ACPI is not enabled by the BIOS and the boot kernel, we need to
* enable it here.
*/
acpi_enable();
}
static void acpi_hibernation_finish(void)
{
acpi_leave_sleep_state(ACPI_STATE_S4);
......@@ -288,6 +297,7 @@ static struct platform_hibernation_ops acpi_hibernation_ops = {
.finish = acpi_hibernation_finish,
.prepare = acpi_hibernation_prepare,
.enter = acpi_hibernation_enter,
.leave = acpi_hibernation_leave,
.pre_restore = acpi_hibernation_pre_restore,
.restore_cleanup = acpi_hibernation_restore_cleanup,
};
......
......@@ -156,6 +156,12 @@ extern void mark_free_pages(struct zone *zone);
* Called after the nonboot CPUs have been disabled and all of the low
* level devices have been shut down (runs with IRQs off).
*
* @leave: Perform the first stage of the cleanup after the system sleep state
* indicated by @set_target() has been left.
* Called right after the control has been passed from the boot kernel to
* the image kernel, before the nonboot CPUs are enabled and before devices
* are resumed. Executed with interrupts disabled.
*
* @pre_restore: Prepare system for the restoration from a hibernation image.
* Called right after devices have been frozen and before the nonboot
* CPUs are disabled (runs with IRQs on).
......@@ -170,6 +176,7 @@ struct platform_hibernation_ops {
void (*finish)(void);
int (*prepare)(void);
int (*enter)(void);
void (*leave)(void);
int (*pre_restore)(void);
void (*restore_cleanup)(void);
};
......
......@@ -92,6 +92,17 @@ static int platform_pre_snapshot(int platform_mode)
hibernation_ops->pre_snapshot() : 0;
}
/**
* platform_leave - prepare the machine for switching to the normal mode
* of operation using the platform driver (called with interrupts disabled)
*/
static void platform_leave(int platform_mode)
{
if (platform_mode && hibernation_ops)
hibernation_ops->leave();
}
/**
* platform_finish - switch the machine to the normal mode of operation
* using the platform driver (must be called after platform_prepare())
......@@ -128,6 +139,51 @@ static void platform_restore_cleanup(int platform_mode)
hibernation_ops->restore_cleanup();
}
/**
* create_image - freeze devices that need to be frozen with interrupts
* off, create the hibernation image and thaw those devices. Control
* reappears in this routine after a restore.
*/
int create_image(int platform_mode)
{
int error;
error = arch_prepare_suspend();
if (error)
return error;
local_irq_disable();
/* At this point, device_suspend() has been called, but *not*
* device_power_down(). We *must* call device_power_down() now.
* Otherwise, drivers for some devices (e.g. interrupt controllers)
* become desynchronized with the actual state of the hardware
* at resume time, and evil weirdness ensues.
*/
error = device_power_down(PMSG_FREEZE);
if (error) {
printk(KERN_ERR "Some devices failed to power down, "
KERN_ERR "aborting suspend\n");
goto Enable_irqs;
}
save_processor_state();
error = swsusp_arch_suspend();
if (error)
printk(KERN_ERR "Error %d while creating the image\n", error);
/* Restore control flow magically appears here */
restore_processor_state();
if (!in_suspend)
platform_leave(platform_mode);
/* NOTE: device_power_up() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
*/
device_power_up();
Enable_irqs:
local_irq_enable();
return error;
}
/**
* hibernation_snapshot - quiesce devices and create the hibernation
* snapshot image.
......@@ -163,7 +219,7 @@ int hibernation_snapshot(int platform_mode)
if (!error) {
if (hibernation_mode != HIBERNATION_TEST) {
in_suspend = 1;
error = swsusp_suspend();
error = create_image(platform_mode);
/* Control returns here after successful restore */
} else {
printk("swsusp debug: Waiting for 5 seconds.\n");
......
......@@ -183,7 +183,6 @@ extern int swsusp_swap_in_use(void);
extern int swsusp_check(void);
extern int swsusp_shrink_memory(void);
extern void swsusp_free(void);
extern int swsusp_suspend(void);
extern int swsusp_resume(void);
extern int swsusp_read(unsigned int *flags_p);
extern int swsusp_write(unsigned int flags);
......
......@@ -270,39 +270,6 @@ int swsusp_shrink_memory(void)
return 0;
}
int swsusp_suspend(void)
{
int error;
if ((error = arch_prepare_suspend()))
return error;
local_irq_disable();
/* At this point, device_suspend() has been called, but *not*
* device_power_down(). We *must* device_power_down() now.
* Otherwise, drivers for some devices (e.g. interrupt controllers)
* become desynchronized with the actual state of the hardware
* at resume time, and evil weirdness ensues.
*/
if ((error = device_power_down(PMSG_FREEZE))) {
printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
goto Enable_irqs;
}
save_processor_state();
if ((error = swsusp_arch_suspend()))
printk(KERN_ERR "Error %d suspending\n", error);
/* Restore control flow magically appears here */
restore_processor_state();
/* NOTE: device_power_up() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
*/
device_power_up();
Enable_irqs:
local_irq_enable();
return error;
}
int swsusp_resume(void)
{
int error;
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment