Merge "lib: spinlock: Cause a watchdog bite on spin_dump"

kernel/locking/spinlock_debug.c

@@ -12,6 +12,8 @@
 #include <linux/debug_locks.h>
 #include <linux/delay.h>
 #include <linux/export.h>
+#include <linux/bug.h>
+#include <soc/qcom/watchdog.h>
 
 void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
 			  struct lock_class_key *key)
@@ -64,6 +66,12 @@ static void spin_dump(raw_spinlock_t *lock, const char *msg)
 		owner ? owner->comm : "<none>",
 		owner ? task_pid_nr(owner) : -1,
 		READ_ONCE(lock->owner_cpu));
+
+#ifdef CONFIG_DEBUG_SPINLOCK_BITE_ON_BUG
+	msm_trigger_wdog_bite();
+#elif defined(CONFIG_DEBUG_SPINLOCK_PANIC_ON_BUG)
+	BUG();
+#endif
 	dump_stack();
 }
 

lib/Kconfig.debug

@@ -1085,6 +1085,29 @@ config LOCK_DEBUGGING_SUPPORT
 	depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
 	default y
 
+choice
+	prompt "Perform Action on spinlock bug"
+	depends on DEBUG_SPINLOCK
+
+	default DEBUG_SPINLOCK_BITE_ON_BUG
+
+	config DEBUG_SPINLOCK_BITE_ON_BUG
+		bool "Cause a Watchdog Bite on Spinlock bug"
+		depends on QCOM_WATCHDOG_V2
+		help
+		  On a spinlock bug, cause a watchdog bite so that we can get
+		  the precise state of the system captured at the time of spin
+		  dump. This is mutually exclusive with the below
+		  DEBUG_SPINLOCK_PANIC_ON_BUG config.
+
+	config DEBUG_SPINLOCK_PANIC_ON_BUG
+		bool "Cause a Kernel Panic on Spinlock bug"
+		help
+		  On a spinlock bug, cause a kernel panic so that we can get the complete
+		  information about the system at the time of spin dump in the dmesg.
+		  This is mutually exclusive with the above DEBUG_SPINLOCK_BITE_ON_BUG.
+endchoice
+
 config PROVE_LOCKING
 	bool "Lock debugging: prove locking correctness"
 	depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT