diff --git a/cr-dump.c b/cr-dump.c
index e32b597c2..ffca7bc08 100644
--- a/cr-dump.c
+++ b/cr-dump.c
@@ -848,7 +848,7 @@ static int seize_threads(struct pstree_item *item)
 			continue;
 
 		pr_info("\tSeizing %d's %d thread\n", item->pid, item->threads[i]);
-		ret = seize_task(item->threads[i]);
+		ret = seize_task(item->threads[i], item->ppid);
 		if (ret < 0)
 			goto err;
 
@@ -887,7 +887,7 @@ static int collect_threads(struct pstree_item *item)
 	return ret;
 }
 
-static struct pstree_item *collect_task(pid_t pid, struct list_head *list)
+static struct pstree_item *collect_task(pid_t pid, pid_t ppid, struct list_head *list)
 {
 	int ret;
 	struct pstree_item *item;
@@ -896,12 +896,13 @@ static struct pstree_item *collect_task(pid_t pid, struct list_head *list)
 	if (!item)
 		goto err;
 
-	ret = seize_task(pid);
+	ret = seize_task(pid, ppid);
 	if (ret < 0)
 		goto err_free;
 
 	pr_info("Seized task %d, state %d\n", pid, ret);
 	item->pid = pid;
+	item->ppid = ppid;
 	item->state = ret;
 
 	ret = collect_threads(item);
@@ -932,13 +933,14 @@ err:
 	return NULL;
 }
 
-static int collect_pstree(pid_t pid, struct list_head *pstree_list, int leader_only)
+static int collect_subtree(pid_t pid, pid_t ppid, struct list_head *pstree_list,
+		int leader_only)
 {
 	struct pstree_item *item;
 	int i;
 
 	pr_info("Collecting tasks starting from %d\n", pid);
-	item = collect_task(pid, pstree_list);
+	item = collect_task(pid, ppid, pstree_list);
 	if (item == NULL)
 		return -1;
 
@@ -946,12 +948,17 @@ static int collect_pstree(pid_t pid, struct list_head *pstree_list, int leader_o
 		return 0;
 
 	for (i = 0; i < item->nr_children; i++)
-		if (collect_pstree(item->children[i], pstree_list, 0) < 0)
+		if (collect_subtree(item->children[i], item->pid, pstree_list, 0) < 0)
 			return -1;
 
 	return 0;
 }
 
+static int collect_pstree(pid_t pid, struct list_head *pstree_list, int leader_only)
+{
+	return collect_subtree(pid, -1, pstree_list, leader_only);
+}
+
 static int dump_pstree(pid_t pid, struct list_head *pstree_list, struct cr_fdset *cr_fdset)
 {
 	struct pstree_item *item;
diff --git a/include/crtools.h b/include/crtools.h
index 8ac10f2ec..ef3f0b30d 100644
--- a/include/crtools.h
+++ b/include/crtools.h
@@ -150,6 +150,7 @@ struct vma_area {
 struct pstree_item {
 	struct list_head	list;
 	pid_t			pid;		/* leader pid */
+	pid_t			ppid;
 	int			state;		/* TASK_XXX constants */
 	u32			nr_children;	/* number of children */
 	u32			nr_threads;	/* number of threads */
diff --git a/include/proc_parse.h b/include/proc_parse.h
index 91714e5a1..383526d8c 100644
--- a/include/proc_parse.h
+++ b/include/proc_parse.h
@@ -8,6 +8,7 @@ struct proc_pid_stat_small {
 	int			pid;
 	char			comm[PROC_TASK_COMM_LEN];
 	char			state;
+	int			ppid;
 };
 
 struct proc_pid_stat {
diff --git a/include/ptrace.h b/include/ptrace.h
index 2665e76b1..87f452871 100644
--- a/include/ptrace.h
+++ b/include/ptrace.h
@@ -32,7 +32,7 @@
 #define PTRACE_O_TRACEVFORKDONE	0x00000020
 #define PTRACE_O_TRACEEXIT	0x00000040
 
-extern int seize_task(pid_t pid);
+extern int seize_task(pid_t pid, pid_t ppid);
 extern int unseize_task(pid_t pid, enum cr_task_state st);
 extern int ptrace_peek_area(pid_t pid, void *dst, void *addr, long bytes);
 extern int ptrace_poke_area(pid_t pid, void *src, void *addr, long bytes);
diff --git a/proc_parse.c b/proc_parse.c
index a443d6e03..d65a11d8a 100644
--- a/proc_parse.c
+++ b/proc_parse.c
@@ -190,10 +190,10 @@ int parse_pid_stat_small(pid_t pid, struct proc_pid_stat_small *s)
 		return -1;
 
 	memset(s, 0, sizeof(*s));
-	n = fscanf(f, "%d " PROC_TASK_COMM_LEN_FMT " %c",
-			&s->pid, s->comm, &s->state);
+	n = fscanf(f, "%d " PROC_TASK_COMM_LEN_FMT " %c %d",
+			&s->pid, s->comm, &s->state, &s->ppid);
 
-	if (n < 3) {
+	if (n < 4) {
 		pr_err("Parsing %d's stat failed (#fields do not match)\n", pid);
 		return -1;
 	}
diff --git a/ptrace.c b/ptrace.c
index 3abb5e572..f7850bd26 100644
--- a/ptrace.c
+++ b/ptrace.c
@@ -40,21 +40,20 @@ int unseize_task(pid_t pid, enum cr_task_state st)
  * up with someone else.
  */
 
-int seize_task(pid_t pid)
+int seize_task(pid_t pid, pid_t ppid)
 {
 	siginfo_t si;
 	int status;
-	int ret;
+	int ret, ret2;
+	struct proc_pid_stat_small ps;
 
 	ret = ptrace(PTRACE_SEIZE, pid, NULL,
 		       (void *)(unsigned long)PTRACE_SEIZE_DEVEL);
+	ret2 = parse_pid_stat_small(pid, &ps);
+	if (ret2 < 0)
+		return -1;
+
 	if (ret < 0) {
-		struct proc_pid_stat_small ps;
-
-		ret = parse_pid_stat_small(pid, &ps);
-		if (ret < 0)
-			return -1;
-
 		if (ps.state != 'Z') {
 			pr_err("Unseizeable non-zombie %d found, state %c\n",
 					pid, ps.state);
@@ -64,6 +63,12 @@ int seize_task(pid_t pid)
 		return TASK_DEAD;
 	}
 
+	if ((ppid != -1) && (ps.ppid != ppid)) {
+		pr_err("Task pid reused while suspending (%d: %d -> %d)\n",
+				pid, ppid, ps.ppid);
+		goto err;
+	}
+
 	ret = ptrace(PTRACE_INTERRUPT, pid, NULL, NULL);
 	if (ret < 0) {
 		pr_perror("SEIZE %d: can't interrupt task", pid);