PM/Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path

In the SNAPSHOT_CREATE_IMAGE ioctl, if the call to hibernation_snapshot() fails, the frozen tasks are not thawed.

And in the case of success, if we happen to exit due to a successful freezer test, all tasks (including those of userspace) are thawed, whereas actually we should have thawed only the kernel threads at that point. Fix both these issues.

Cc [email protected]

Signed-off-by Srivatsa S. Bhat <[email protected]>

---
This applies on top of the patch posted at https://lkml.org/lkml/2012/1/27/501

 kernel/power/user.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

kernel/power/user.c +4 -2

index e5a21a8..3e10007 100644
@@ -249,13 +249,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 		}
 		pm_restore_gfp_mask();
 		error = hibernation_snapshot(data->platform_support);
-		if (!error) {
+		if (error) {
+			thaw_kernel_threads();
+		} else {
 			error = put_user(in_suspend, (int __user *)arg);
 			if (!error && !freezer_test_done)
 				data->ready = 1;
 			if (freezer_test_done) {
 				freezer_test_done = false;
-				thaw_processes();
+				thaw_kernel_threads();
 			}
 		}
 		break;