From: Chen Yu <yu.c.chen@intel.com>
Date: Fri, 14 Apr 2023 20:10:26 +0800
Subject: [PATCH] PM: hibernate: Turn snapshot_test into global variable
References: bsc#1012628
Patch-mainline: 6.3.2
Git-commit: 08169a162f97819d3e5b4a342bb9cf5137787154

[ Upstream commit 08169a162f97819d3e5b4a342bb9cf5137787154 ]

There is need to check snapshot_test and open block device
in different mode, so as to avoid the race condition.

No functional changes intended.

Suggested-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 5904de0d735b ("PM: hibernate: Do not get block device exclusively in test_resume mode")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 kernel/power/hibernate.c | 7 ++++++-
 kernel/power/power.h     | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 793c55a2..aa551b09 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -64,6 +64,7 @@ enum {
 static int hibernation_mode = HIBERNATION_SHUTDOWN;
 
 bool freezer_test_done;
+bool snapshot_test;
 
 static const struct platform_hibernation_ops *hibernation_ops;
 
@@ -716,7 +717,6 @@ static int load_image_and_restore(void)
  */
 int hibernate(void)
 {
-	bool snapshot_test = false;
 	unsigned int sleep_flags;
 	int error;
 
@@ -744,6 +744,9 @@ int hibernate(void)
 	if (error)
 		goto Exit;
 
+	/* protected by system_transition_mutex */
+	snapshot_test = false;
+
 	lock_device_hotplug();
 	/* Allocate memory management structures */
 	error = create_basic_memory_bitmaps();
@@ -940,6 +943,8 @@ static int software_resume(void)
 	 */
 	mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
 
+	snapshot_test = false;
+
 	if (swsusp_resume_device)
 		goto Check_image;
 
diff --git a/kernel/power/power.h b/kernel/power/power.h
index b4f43394..b83c8d5e 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -59,6 +59,7 @@ asmlinkage int swsusp_save(void);
 
 /* kernel/power/hibernate.c */
 extern bool freezer_test_done;
+extern bool snapshot_test;
 
 extern int hibernation_snapshot(int platform_mode);
 extern int hibernation_restore(int platform_mode);
-- 
2.35.3