Commit 67e59f8d authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge branch 'pm-sysoff' 

Merge fixes for regressions introduced by the recent rework of the
system reboot/poweroff code.

* pm-sysoff:
  kernel/reboot: Fix powering off using a non-syscall code paths
  kernel/reboot: Use static handler for register_platform_power_off()
parents 32d4fd57 2b8c612c

kernel/reboot.c

+62 −25
Original line number Diff line number Diff line
@@ -315,6 +315,43 @@ static int sys_off_notify(struct notifier_block *nb, 
	return handler->sys_off_cb(&data);

}



static struct sys_off_handler platform_sys_off_handler;



static struct sys_off_handler *alloc_sys_off_handler(int priority)

{

	struct sys_off_handler *handler;

	gfp_t flags;



	/*

	 * Platforms like m68k can't allocate sys_off handler dynamically

	 * at the early boot time because memory allocator isn't available yet.

	 */

	if (priority == SYS_OFF_PRIO_PLATFORM) {

		handler = &platform_sys_off_handler;

		if (handler->cb_data)

			return ERR_PTR(-EBUSY);

	} else {

		if (system_state > SYSTEM_RUNNING)

			flags = GFP_ATOMIC;

		else

			flags = GFP_KERNEL;



		handler = kzalloc(sizeof(*handler), flags);

		if (!handler)

			return ERR_PTR(-ENOMEM);

	}



	return handler;

}



static void free_sys_off_handler(struct sys_off_handler *handler)

{

	if (handler == &platform_sys_off_handler)

		memset(handler, 0, sizeof(*handler));

	else

		kfree(handler);

}



/**

 *	register_sys_off_handler - Register sys-off handler

 *	@mode: Sys-off mode
@@ -345,9 +382,9 @@ register_sys_off_handler(enum sys_off_mode mode, 
	struct sys_off_handler *handler;

	int err;



	handler = kzalloc(sizeof(*handler), GFP_KERNEL);

	if (!handler)

		return ERR_PTR(-ENOMEM);

	handler = alloc_sys_off_handler(priority);

	if (IS_ERR(handler))

		return handler;



	switch (mode) {

	case SYS_OFF_MODE_POWER_OFF_PREPARE:
@@ -364,7 +401,7 @@ register_sys_off_handler(enum sys_off_mode mode, 
		break;



	default:

		kfree(handler);

		free_sys_off_handler(handler);

		return ERR_PTR(-EINVAL);

	}
@@ -391,7 +428,7 @@ register_sys_off_handler(enum sys_off_mode mode, 
	}



	if (err) {

		kfree(handler);

		free_sys_off_handler(handler);

		return ERR_PTR(err);

	}
@@ -409,7 +446,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler) 
{

	int err;



	if (!handler)

	if (IS_ERR_OR_NULL(handler))

		return;



	if (handler->blocking)
@@ -422,7 +459,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler) 
	/* sanity check, shall never happen */

	WARN_ON(err);



	kfree(handler);

	free_sys_off_handler(handler);

}

EXPORT_SYMBOL_GPL(unregister_sys_off_handler);
@@ -584,7 +621,23 @@ static void do_kernel_power_off_prepare(void) 
 */

void do_kernel_power_off(void)

{

	struct sys_off_handler *sys_off = NULL;



	/*

	 * Register sys-off handlers for legacy PM callback. This allows

	 * legacy PM callbacks temporary co-exist with the new sys-off API.

	 *

	 * TODO: Remove legacy handlers once all legacy PM users will be

	 *       switched to the sys-off based APIs.

	 */

	if (pm_power_off)

		sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,

						   SYS_OFF_PRIO_DEFAULT,

						   legacy_pm_power_off, NULL);



	atomic_notifier_call_chain(&power_off_handler_list, 0, NULL);



	unregister_sys_off_handler(sys_off);

}



/**
@@ -595,7 +648,8 @@ void do_kernel_power_off(void) 
 */

bool kernel_can_power_off(void)

{

	return !atomic_notifier_call_chain_is_empty(&power_off_handler_list);

	return !atomic_notifier_call_chain_is_empty(&power_off_handler_list) ||

		pm_power_off;

}

EXPORT_SYMBOL_GPL(kernel_can_power_off);
@@ -630,7 +684,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, 
		void __user *, arg)

{

	struct pid_namespace *pid_ns = task_active_pid_ns(current);

	struct sys_off_handler *sys_off = NULL;

	char buffer[256];

	int ret = 0;
@@ -655,21 +708,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, 
	if (ret)

		return ret;



	/*

	 * Register sys-off handlers for legacy PM callback. This allows

	 * legacy PM callbacks temporary co-exist with the new sys-off API.

	 *

	 * TODO: Remove legacy handlers once all legacy PM users will be

	 *       switched to the sys-off based APIs.

	 */

	if (pm_power_off) {

		sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,

						   SYS_OFF_PRIO_DEFAULT,

						   legacy_pm_power_off, NULL);

		if (IS_ERR(sys_off))

			return PTR_ERR(sys_off);

	}



	/* Instead of trying to make the power_off code look like

	 * halt when pm_power_off is not set do it the easy way.

	 */
@@ -727,7 +765,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, 
		break;

	}

	mutex_unlock(&system_transition_mutex);

	unregister_sys_off_handler(sys_off);

	return ret;

}