[CRIU] [PATCH] ptrace: the task state is restored automatically

[Andrew Vagin]

It's a feature of PTRACE_SEIZE.
So we need to do something, only if we want to change the state.

Signed-off-by: Andrew Vagin <avagin at openvz.org>
---
 cr-dump.c        | 5 +----
 cr-exec.c        | 2 +-
 include/ptrace.h | 2 +-
 ptrace.c         | 4 ++--
 4 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/cr-dump.c b/cr-dump.c
index 6685c1f..e02e4ae 100644
--- a/cr-dump.c
+++ b/cr-dump.c
@@ -808,10 +808,7 @@ static void unseize_task_and_threads(const struct pstree_item *item, int st)
 	 * the item->state is the state task was in when we seized one.
 	 */
 
-	if (st == TASK_ALIVE)
-		unseize_task(item->pid.real, item->state);
-	else
-		unseize_task(item->pid.real, st); /* item->pid will be here */
+	unseize_task(item->pid.real, item->state, st);
 
 	for (i = 1; i < item->nr_threads; i++)
 		ptrace(PTRACE_DETACH, item->threads[i].real, NULL, NULL);
diff --git a/cr-exec.c b/cr-exec.c
index 5ada6f6..987fe5b 100644
--- a/cr-exec.c
+++ b/cr-exec.c
@@ -153,7 +153,7 @@ int cr_exec(int pid, char **opt)
 
 	parasite_cure_seized(ctl);
 out_unseize:
-	unseize_task(pid, prev_state);
+	unseize_task(pid, prev_state, prev_state);
 out:
 	return ret;
 }
diff --git a/include/ptrace.h b/include/ptrace.h
index d8034b4..ce892b0 100644
--- a/include/ptrace.h
+++ b/include/ptrace.h
@@ -56,7 +56,7 @@ struct ptrace_peeksiginfo_args {
 #define SI_EVENT(_si_code)	(((_si_code) & 0xFFFF) >> 8)
 
 extern int seize_task(pid_t pid, pid_t ppid, pid_t *pgid, pid_t *sid);
-extern int unseize_task(pid_t pid, int state);
+extern int unseize_task(pid_t pid, int orig_state, int state);
 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);
 extern int ptrace_swap_area(pid_t pid, void *dst, void *src, long bytes);
diff --git a/ptrace.c b/ptrace.c
index 6034dab..4b91e62 100644
--- a/ptrace.c
+++ b/ptrace.c
@@ -19,13 +19,13 @@
 #include "ptrace.h"
 #include "proc_parse.h"
 
-int unseize_task(pid_t pid, int st)
+int unseize_task(pid_t pid, int orig_st, int st)
 {
 	pr_debug("\tUnseizing %d into %d\n", pid, st);
 
 	if (st == TASK_DEAD)
 		kill(pid, SIGKILL);
-	else if (st == TASK_STOPPED)
+	else if (st == TASK_STOPPED && orig_st == TASK_ALIVE)
 		kill(pid, SIGSTOP);
 	else if (st == TASK_ALIVE)
 		/* do nothing */ ;
-- 
1.8.3.1