Commit a51f67a4 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'pm-fix-for-3.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Power management fix for 3.3-rc2

Fix for a hibernate (s2disk) regression introduced during the 3.2
merge window that causes s2disk to trigger BUG_ON() in
freeze_workqueues_begin() if there is not enough swap space to save
the image.

* tag 'pm-fix-for-3.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Hibernate: Fix s2disk regression related to freezing workqueues
parents 0a962657 181e9bde

include/linux/freezer.h

+2 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ extern bool __refrigerator(bool check_kthr_stop); 
extern int freeze_processes(void);

extern int freeze_kernel_threads(void);

extern void thaw_processes(void);

extern void thaw_kernel_threads(void);



static inline bool try_to_freeze(void)

{
@@ -174,6 +175,7 @@ static inline bool __refrigerator(bool check_kthr_stop) { return false; } 
static inline int freeze_processes(void) { return -ENOSYS; }

static inline int freeze_kernel_threads(void) { return -ENOSYS; }

static inline void thaw_processes(void) {}

static inline void thaw_kernel_threads(void) {}



static inline bool try_to_freeze(void) { return false; }

kernel/power/process.c

+19 −0
Original line number Diff line number Diff line
@@ -188,3 +188,22 @@ void thaw_processes(void) 
	printk("done.\n");

}



void thaw_kernel_threads(void)

{

	struct task_struct *g, *p;



	pm_nosig_freezing = false;

	printk("Restarting kernel threads ... ");



	thaw_workqueues();



	read_lock(&tasklist_lock);

	do_each_thread(g, p) {

		if (p->flags & (PF_KTHREAD | PF_WQ_WORKER))

			__thaw_task(p);

	} while_each_thread(g, p);

	read_unlock(&tasklist_lock);



	schedule();

	printk("done.\n");

}

kernel/power/user.c

+9 −0
Original line number Diff line number Diff line
@@ -274,6 +274,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, 
		swsusp_free();

		memset(&data->handle, 0, sizeof(struct snapshot_handle));

		data->ready = 0;

		/*

		 * It is necessary to thaw kernel threads here, because

		 * SNAPSHOT_CREATE_IMAGE may be invoked directly after

		 * SNAPSHOT_FREE.  In that case, if kernel threads were not

		 * thawed, the preallocation of memory carried out by

		 * hibernation_snapshot() might run into problems (i.e. it

		 * might fail or even deadlock).

		 */

		thaw_kernel_threads();

		break;



	case SNAPSHOT_PREF_IMAGE_SIZE:

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