2 files changed, 19 insertions, 0 deletions

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 160b5d6df7cb..db933d063bfc 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -76,7 +76,11 @@ module_param(lock_stat, int, 0644);
 #define lock_stat 0
 #endif
 
+#ifdef CONFIG_BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK
+static int crossrelease_fullstack = 1;
+#else
 static int crossrelease_fullstack;
+#endif
 static int __init allow_crossrelease_fullstack(char *str)
 {
         crossrelease_fullstack = 1;
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c1e720a22c71..2b439a515c30 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1179,6 +1179,21 @@ config LOCKDEP_COMPLETIONS
          A deadlock caused by wait_for_completion() and complete() can be
          detected by lockdep using crossrelease feature.
 
+config BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK
+        bool "Enable the boot parameter, crossrelease_fullstack"
+        depends on LOCKDEP_CROSSRELEASE
+        default n
+        help
+         The lockdep "cross-release" feature needs to record stack traces
+         (of calling functions) for all acquisitions, for eventual later
+         use during analysis. By default only a single caller is recorded,
+         because the unwind operation can be very expensive with deeper
+         stack chains.
+
+         However a boot parameter, crossrelease_fullstack, was
+         introduced since sometimes deeper traces are required for full
+         analysis. This option turns on the boot parameter.
+
 config DEBUG_LOCKDEP
         bool "Lock dependency engine debugging"
         depends on DEBUG_KERNEL && LOCKDEP