1 files changed, 114 insertions, 13 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e4fcbd12cf6e..e5889b1a33ff 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -48,7 +48,7 @@ config DEBUG_KERNEL
 config LOG_BUF_SHIFT
         int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" if DEBUG_KERNEL
         range 12 21
-        default 17 if S390
+        default 17 if S390 || LOCKDEP
         default 16 if X86_NUMAQ || IA64
         default 15 if SMP
         default 14
@@ -107,7 +107,7 @@ config DEBUG_SLAB_LEAK
 
 config DEBUG_PREEMPT
         bool "Debug preemptible kernel"
-        depends on DEBUG_KERNEL && PREEMPT
+        depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT
         default y
         help
           If you say Y here then the kernel will use a debug variant of the
@@ -115,14 +115,6 @@ config DEBUG_PREEMPT
           if kernel code uses it in a preemption-unsafe way. Also, the kernel
           will detect preemption count underflows.
 
-config DEBUG_MUTEXES
-        bool "Mutex debugging, deadlock detection"
-        default n
-        depends on DEBUG_KERNEL
-        help
-         This allows mutex semantics violations and mutex related deadlocks
-         (lockups) to be detected and reported automatically.
-
 config DEBUG_RT_MUTEXES
         bool "RT Mutex debugging, deadlock detection"
         depends on DEBUG_KERNEL && RT_MUTEXES
@@ -142,7 +134,7 @@ config RT_MUTEX_TESTER
           This option enables a rt-mutex tester.
 
 config DEBUG_SPINLOCK
-        bool "Spinlock debugging"
+        bool "Spinlock and rw-lock debugging: basic checks"
         depends on DEBUG_KERNEL
         help
           Say Y here and build SMP to catch missing spinlock initialization
@@ -150,13 +142,122 @@ config DEBUG_SPINLOCK
           best used in conjunction with the NMI watchdog so that spinlock
           deadlocks are also debuggable.
 
+config DEBUG_MUTEXES
+        bool "Mutex debugging: basic checks"
+        depends on DEBUG_KERNEL
+        help
+         This feature allows mutex semantics violations to be detected and
+         reported.
+
+config DEBUG_RWSEMS
+        bool "RW-sem debugging: basic checks"
+        depends on DEBUG_KERNEL
+        help
+         This feature allows read-write semaphore semantics violations to
+         be detected and reported.
+
+config DEBUG_LOCK_ALLOC
+        bool "Lock debugging: detect incorrect freeing of live locks"
+        depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
+        select DEBUG_SPINLOCK
+        select DEBUG_MUTEXES
+        select DEBUG_RWSEMS
+        select LOCKDEP
+        help
+         This feature will check whether any held lock (spinlock, rwlock,
+         mutex or rwsem) is incorrectly freed by the kernel, via any of the
+         memory-freeing routines (kfree(), kmem_cache_free(), free_pages(),
+         vfree(), etc.), whether a live lock is incorrectly reinitialized via
+         spin_lock_init()/mutex_init()/etc., or whether there is any lock
+         held during task exit.
+
+config PROVE_LOCKING
+        bool "Lock debugging: prove locking correctness"
+        depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
+        select LOCKDEP
+        select DEBUG_SPINLOCK
+        select DEBUG_MUTEXES
+        select DEBUG_RWSEMS
+        select DEBUG_LOCK_ALLOC
+        default n
+        help
+         This feature enables the kernel to prove that all locking
+         that occurs in the kernel runtime is mathematically
+         correct: that under no circumstance could an arbitrary (and
+         not yet triggered) combination of observed locking
+         sequences (on an arbitrary number of CPUs, running an
+         arbitrary number of tasks and interrupt contexts) cause a
+         deadlock.
+
+         In short, this feature enables the kernel to report locking
+         related deadlocks before they actually occur.
+
+         The proof does not depend on how hard and complex a
+         deadlock scenario would be to trigger: how many
+         participant CPUs, tasks and irq-contexts would be needed
+         for it to trigger. The proof also does not depend on
+         timing: if a race and a resulting deadlock is possible
+         theoretically (no matter how unlikely the race scenario
+         is), it will be proven so and will immediately be
+         reported by the kernel (once the event is observed that
+         makes the deadlock theoretically possible).
+
+         If a deadlock is impossible (i.e. the locking rules, as
+         observed by the kernel, are mathematically correct), the
+         kernel reports nothing.
+
+         NOTE: this feature can also be enabled for rwlocks, mutexes
+         and rwsems - in which case all dependencies between these
+         different locking variants are observed and mapped too, and
+         the proof of observed correctness is also maintained for an
+         arbitrary combination of these separate locking variants.
+
+         For more details, see Documentation/lockdep-design.txt.
+
+config LOCKDEP
+        bool
+        depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
+        select STACKTRACE
+        select FRAME_POINTER
+        select KALLSYMS
+        select KALLSYMS_ALL
+
+config DEBUG_LOCKDEP
+        bool "Lock dependency engine debugging"
+        depends on LOCKDEP
+        help
+          If you say Y here, the lock dependency engine will do
+          additional runtime checks to debug itself, at the price
+          of more runtime overhead.
+
+config TRACE_IRQFLAGS
+        bool
+        default y
+        depends on TRACE_IRQFLAGS_SUPPORT
+        depends on PROVE_LOCKING
+
 config DEBUG_SPINLOCK_SLEEP
-        bool "Sleep-inside-spinlock checking"
+        bool "Spinlock debugging: sleep-inside-spinlock checking"
         depends on DEBUG_KERNEL
         help
           If you say Y here, various routines which may sleep will become very
           noisy if they are called with a spinlock held.
 
+config DEBUG_LOCKING_API_SELFTESTS
+        bool "Locking API boot-time self-tests"
+        depends on DEBUG_KERNEL
+        help
+          Say Y here if you want the kernel to run a short self-test during
+          bootup. The self-test checks whether common types of locking bugs
+          are detected by debugging mechanisms or not. (if you disable
+          lock debugging then those bugs wont be detected of course.)
+          The following locking APIs are covered: spinlocks, rwlocks,
+          mutexes and rwsems.
+
+config STACKTRACE
+        bool
+        depends on STACKTRACE_SUPPORT
+
 config DEBUG_KOBJECT
         bool "kobject debugging"
         depends on DEBUG_KERNEL
@@ -212,7 +313,7 @@ config DEBUG_VM
 
 config FRAME_POINTER
         bool "Compile the kernel with frame pointers"
-        depends on DEBUG_KERNEL && (X86 || CRIS || M68K || M68KNOMMU || FRV || UML)
+        depends on DEBUG_KERNEL && (X86 || CRIS || M68K || M68KNOMMU || FRV || UML || S390)
         default y if DEBUG_INFO && UML
         help
           If you say Y here the resulting kernel image will be slightly larger