3 files changed, 47 insertions, 25 deletions

diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 79833170bb9c..6233f3b4ae66 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -190,7 +190,7 @@ config APM_EMULATION
           notification of APM "events" (e.g. battery status change).
 
           In order to use APM, you will need supporting software. For location
-          and more information, read <file:Documentation/pm.txt> and the
+          and more information, read <file:Documentation/power/pm.txt> and the
           Battery Powered Linux mini-HOWTO, available from
           <http://www.tldp.org/docs.html#howto>.
 
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 7c2118f9597f..f1d0b345c9ba 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -75,22 +75,15 @@ void refrigerator(void)
         __set_current_state(save);
 }
 
-static void fake_signal_wake_up(struct task_struct *p, int resume)
+static void fake_signal_wake_up(struct task_struct *p)
 {
         unsigned long flags;
 
         spin_lock_irqsave(&p->sighand->siglock, flags);
-        signal_wake_up(p, resume);
+        signal_wake_up(p, 0);
         spin_unlock_irqrestore(&p->sighand->siglock, flags);
 }
 
-static void send_fake_signal(struct task_struct *p)
-{
-        if (task_is_stopped(p))
-                force_sig_specific(SIGSTOP, p);
-        fake_signal_wake_up(p, task_is_stopped(p));
-}
-
 static int has_mm(struct task_struct *p)
 {
         return (p->mm && !(p->flags & PF_BORROWED_MM));
@@ -121,7 +114,7 @@ static int freeze_task(struct task_struct *p, int with_mm_only)
         if (freezing(p)) {
                 if (has_mm(p)) {
                         if (!signal_pending(p))
-                                fake_signal_wake_up(p, 0);
+                                fake_signal_wake_up(p);
                 } else {
                         if (with_mm_only)
                                 ret = 0;
@@ -135,7 +128,7 @@ static int freeze_task(struct task_struct *p, int with_mm_only)
                 } else {
                         if (has_mm(p)) {
                                 set_freeze_flag(p);
-                                send_fake_signal(p);
+                                fake_signal_wake_up(p);
                         } else {
                                 if (with_mm_only) {
                                         ret = 0;
@@ -182,15 +175,17 @@ static int try_to_freeze_tasks(int freeze_user_space)
                         if (frozen(p) || !freezeable(p))
                                 continue;
 
-                        if (task_is_traced(p) && frozen(p->parent)) {
-                                cancel_freezing(p);
-                                continue;
-                        }
-
                         if (!freeze_task(p, freeze_user_space))
                                 continue;
 
-                        if (!freezer_should_skip(p))
+                        /*
+                         * Now that we've done set_freeze_flag, don't
+                         * perturb a task in TASK_STOPPED or TASK_TRACED.
+                         * It is "frozen enough".  If the task does wake
+                         * up, it will immediately call try_to_freeze.
+                         */
+                        if (!task_is_stopped_or_traced(p) &&
+                            !freezer_should_skip(p))
                                 todo++;
                 } while_each_thread(g, p);
                 read_unlock(&tasklist_lock);
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 72a020cabb4c..5f91a07c4eac 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -447,7 +447,7 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
  *      of @bm->cur_zone_bm are updated.
  */
 
-static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
+static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
                                 void **addr, unsigned int *bit_nr)
 {
         struct zone_bitmap *zone_bm;
@@ -461,7 +461,8 @@ static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
                 while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
                         zone_bm = zone_bm->next;
 
-                        BUG_ON(!zone_bm);
+                        if (!zone_bm)
+                                return -EFAULT;
                 }
                 bm->cur.zone_bm = zone_bm;
         }
@@ -479,23 +480,40 @@ static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
         pfn -= bb->start_pfn;
         *bit_nr = pfn % BM_BITS_PER_CHUNK;
         *addr = bb->data + pfn / BM_BITS_PER_CHUNK;
+        return 0;
 }
 
 static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
 {
         void *addr;
         unsigned int bit;
+        int error;
 
-        memory_bm_find_bit(bm, pfn, &addr, &bit);
+        error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+        BUG_ON(error);
         set_bit(bit, addr);
 }
 
+static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
+{
+        void *addr;
+        unsigned int bit;
+        int error;
+
+        error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+        if (!error)
+                set_bit(bit, addr);
+        return error;
+}
+
 static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
 {
         void *addr;
         unsigned int bit;
+        int error;
 
-        memory_bm_find_bit(bm, pfn, &addr, &bit);
+        error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+        BUG_ON(error);
         clear_bit(bit, addr);
 }
 
@@ -503,8 +521,10 @@ static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
 {
         void *addr;
         unsigned int bit;
+        int error;
 
-        memory_bm_find_bit(bm, pfn, &addr, &bit);
+        error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+        BUG_ON(error);
         return test_bit(bit, addr);
 }
 
@@ -709,8 +729,15 @@ static void mark_nosave_pages(struct memory_bitmap *bm)
                                 region->end_pfn << PAGE_SHIFT);
 
                 for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
-                        if (pfn_valid(pfn))
-                                memory_bm_set_bit(bm, pfn);
+                        if (pfn_valid(pfn)) {
+                                /*
+                                 * It is safe to ignore the result of
+                                 * mem_bm_set_bit_check() here, since we won't
+                                 * touch the PFNs for which the error is
+                                 * returned anyway.
+                                 */
+                                mem_bm_set_bit_check(bm, pfn);
+                        }
         }
 }