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.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org

1 files changed, 4 insertions, 2 deletions

diff --git a/kernel/power/user.c b/kernel/power/user.c
index e5a21a857302..3e100075b13c 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -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;