forked from luck/tmp_suning_uos_patched
lockdep: Fix lockdep recursion
Steve reported that lockdep_assert*irq*(), when nested inside lockdep
itself, will trigger a false-positive.
One example is the stack-trace code, as called from inside lockdep,
triggering tracing, which in turn calls RCU, which then uses
lockdep_assert_irqs_disabled().
Fixes: a21ee6055c ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra
Ingo Molnar
parent
2bb8945bcc
commit
4d004099a6
|
|
@ -534,6 +534,7 @@ do { \
|
|||
|
||||
DECLARE_PER_CPU(int, hardirqs_enabled);
|
||||
DECLARE_PER_CPU(int, hardirq_context);
|
||||
DECLARE_PER_CPU(unsigned int, lockdep_recursion);
|
||||
|
||||
/*
|
||||
* The below lockdep_assert_*() macros use raw_cpu_read() to access the above
|
||||
|
|
@ -543,25 +544,27 @@ DECLARE_PER_CPU(int, hardirq_context);
|
|||
* read the value from our previous CPU.
|
||||
*/
|
||||
|
||||
#define __lockdep_enabled (debug_locks && !raw_cpu_read(lockdep_recursion))
|
||||
|
||||
#define lockdep_assert_irqs_enabled() \
|
||||
do { \
|
||||
WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirqs_enabled)); \
|
||||
WARN_ON_ONCE(__lockdep_enabled && !raw_cpu_read(hardirqs_enabled)); \
|
||||
} while (0)
|
||||
|
||||
#define lockdep_assert_irqs_disabled() \
|
||||
do { \
|
||||
WARN_ON_ONCE(debug_locks && raw_cpu_read(hardirqs_enabled)); \
|
||||
WARN_ON_ONCE(__lockdep_enabled && raw_cpu_read(hardirqs_enabled)); \
|
||||
} while (0)
|
||||
|
||||
#define lockdep_assert_in_irq() \
|
||||
do { \
|
||||
WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirq_context)); \
|
||||
WARN_ON_ONCE(__lockdep_enabled && !raw_cpu_read(hardirq_context)); \
|
||||
} while (0)
|
||||
|
||||
#define lockdep_assert_preemption_enabled() \
|
||||
do { \
|
||||
WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
|
||||
debug_locks && \
|
||||
__lockdep_enabled && \
|
||||
(preempt_count() != 0 || \
|
||||
!raw_cpu_read(hardirqs_enabled))); \
|
||||
} while (0)
|
||||
|
|
@ -569,7 +572,7 @@ do { \
|
|||
#define lockdep_assert_preemption_disabled() \
|
||||
do { \
|
||||
WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
|
||||
debug_locks && \
|
||||
__lockdep_enabled && \
|
||||
(preempt_count() == 0 && \
|
||||
raw_cpu_read(hardirqs_enabled))); \
|
||||
} while (0)
|
||||
|
|
|
|||
|
|
@ -76,6 +76,23 @@ module_param(lock_stat, int, 0644);
|
|||
#define lock_stat 0
|
||||
#endif
|
||||
|
||||
DEFINE_PER_CPU(unsigned int, lockdep_recursion);
|
||||
EXPORT_PER_CPU_SYMBOL_GPL(lockdep_recursion);
|
||||
|
||||
static inline bool lockdep_enabled(void)
|
||||
{
|
||||
if (!debug_locks)
|
||||
return false;
|
||||
|
||||
if (raw_cpu_read(lockdep_recursion))
|
||||
return false;
|
||||
|
||||
if (current->lockdep_recursion)
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* lockdep_lock: protects the lockdep graph, the hashes and the
|
||||
* class/list/hash allocators.
|
||||
|
|
@ -93,7 +110,7 @@ static inline void lockdep_lock(void)
|
|||
|
||||
arch_spin_lock(&__lock);
|
||||
__owner = current;
|
||||
current->lockdep_recursion++;
|
||||
__this_cpu_inc(lockdep_recursion);
|
||||
}
|
||||
|
||||
static inline void lockdep_unlock(void)
|
||||
|
|
@ -101,7 +118,7 @@ static inline void lockdep_unlock(void)
|
|||
if (debug_locks && DEBUG_LOCKS_WARN_ON(__owner != current))
|
||||
return;
|
||||
|
||||
current->lockdep_recursion--;
|
||||
__this_cpu_dec(lockdep_recursion);
|
||||
__owner = NULL;
|
||||
arch_spin_unlock(&__lock);
|
||||
}
|
||||
|
|
@ -393,10 +410,15 @@ void lockdep_init_task(struct task_struct *task)
|
|||
task->lockdep_recursion = 0;
|
||||
}
|
||||
|
||||
static __always_inline void lockdep_recursion_inc(void)
|
||||
{
|
||||
__this_cpu_inc(lockdep_recursion);
|
||||
}
|
||||
|
||||
static __always_inline void lockdep_recursion_finish(void)
|
||||
{
|
||||
if (WARN_ON_ONCE((--current->lockdep_recursion) & LOCKDEP_RECURSION_MASK))
|
||||
current->lockdep_recursion = 0;
|
||||
if (WARN_ON_ONCE(__this_cpu_dec_return(lockdep_recursion)))
|
||||
__this_cpu_write(lockdep_recursion, 0);
|
||||
}
|
||||
|
||||
void lockdep_set_selftest_task(struct task_struct *task)
|
||||
|
|
@ -3659,7 +3681,7 @@ void lockdep_hardirqs_on_prepare(unsigned long ip)
|
|||
if (unlikely(in_nmi()))
|
||||
return;
|
||||
|
||||
if (unlikely(current->lockdep_recursion & LOCKDEP_RECURSION_MASK))
|
||||
if (unlikely(__this_cpu_read(lockdep_recursion)))
|
||||
return;
|
||||
|
||||
if (unlikely(lockdep_hardirqs_enabled())) {
|
||||
|
|
@ -3695,7 +3717,7 @@ void lockdep_hardirqs_on_prepare(unsigned long ip)
|
|||
|
||||
current->hardirq_chain_key = current->curr_chain_key;
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__trace_hardirqs_on_caller();
|
||||
lockdep_recursion_finish();
|
||||
}
|
||||
|
|
@ -3728,7 +3750,7 @@ void noinstr lockdep_hardirqs_on(unsigned long ip)
|
|||
goto skip_checks;
|
||||
}
|
||||
|
||||
if (unlikely(current->lockdep_recursion & LOCKDEP_RECURSION_MASK))
|
||||
if (unlikely(__this_cpu_read(lockdep_recursion)))
|
||||
return;
|
||||
|
||||
if (lockdep_hardirqs_enabled()) {
|
||||
|
|
@ -3781,7 +3803,7 @@ void noinstr lockdep_hardirqs_off(unsigned long ip)
|
|||
if (in_nmi()) {
|
||||
if (!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_NMI))
|
||||
return;
|
||||
} else if (current->lockdep_recursion & LOCKDEP_RECURSION_MASK)
|
||||
} else if (__this_cpu_read(lockdep_recursion))
|
||||
return;
|
||||
|
||||
/*
|
||||
|
|
@ -3814,7 +3836,7 @@ void lockdep_softirqs_on(unsigned long ip)
|
|||
{
|
||||
struct irqtrace_events *trace = ¤t->irqtrace;
|
||||
|
||||
if (unlikely(!debug_locks || current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
/*
|
||||
|
|
@ -3829,7 +3851,7 @@ void lockdep_softirqs_on(unsigned long ip)
|
|||
return;
|
||||
}
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
/*
|
||||
* We'll do an OFF -> ON transition:
|
||||
*/
|
||||
|
|
@ -3852,7 +3874,7 @@ void lockdep_softirqs_on(unsigned long ip)
|
|||
*/
|
||||
void lockdep_softirqs_off(unsigned long ip)
|
||||
{
|
||||
if (unlikely(!debug_locks || current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
/*
|
||||
|
|
@ -4233,11 +4255,11 @@ void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
|
|||
if (subclass) {
|
||||
unsigned long flags;
|
||||
|
||||
if (DEBUG_LOCKS_WARN_ON(current->lockdep_recursion))
|
||||
if (DEBUG_LOCKS_WARN_ON(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
register_lock_class(lock, subclass, 1);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -4920,11 +4942,11 @@ void lock_set_class(struct lockdep_map *lock, const char *name,
|
|||
{
|
||||
unsigned long flags;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
check_flags(flags);
|
||||
if (__lock_set_class(lock, name, key, subclass, ip))
|
||||
check_chain_key(current);
|
||||
|
|
@ -4937,11 +4959,11 @@ void lock_downgrade(struct lockdep_map *lock, unsigned long ip)
|
|||
{
|
||||
unsigned long flags;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
check_flags(flags);
|
||||
if (__lock_downgrade(lock, ip))
|
||||
check_chain_key(current);
|
||||
|
|
@ -4979,7 +5001,7 @@ static void verify_lock_unused(struct lockdep_map *lock, struct held_lock *hlock
|
|||
|
||||
static bool lockdep_nmi(void)
|
||||
{
|
||||
if (current->lockdep_recursion & LOCKDEP_RECURSION_MASK)
|
||||
if (raw_cpu_read(lockdep_recursion))
|
||||
return false;
|
||||
|
||||
if (!in_nmi())
|
||||
|
|
@ -5000,7 +5022,10 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
|
|||
|
||||
trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip);
|
||||
|
||||
if (unlikely(current->lockdep_recursion)) {
|
||||
if (!debug_locks)
|
||||
return;
|
||||
|
||||
if (unlikely(!lockdep_enabled())) {
|
||||
/* XXX allow trylock from NMI ?!? */
|
||||
if (lockdep_nmi() && !trylock) {
|
||||
struct held_lock hlock;
|
||||
|
|
@ -5023,7 +5048,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
|
|||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__lock_acquire(lock, subclass, trylock, read, check,
|
||||
irqs_disabled_flags(flags), nest_lock, ip, 0, 0);
|
||||
lockdep_recursion_finish();
|
||||
|
|
@ -5037,13 +5062,13 @@ void lock_release(struct lockdep_map *lock, unsigned long ip)
|
|||
|
||||
trace_lock_release(lock, ip);
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
if (__lock_release(lock, ip))
|
||||
check_chain_key(current);
|
||||
lockdep_recursion_finish();
|
||||
|
|
@ -5056,13 +5081,13 @@ noinstr int lock_is_held_type(const struct lockdep_map *lock, int read)
|
|||
unsigned long flags;
|
||||
int ret = 0;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return 1; /* avoid false negative lockdep_assert_held() */
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
ret = __lock_is_held(lock, read);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -5077,13 +5102,13 @@ struct pin_cookie lock_pin_lock(struct lockdep_map *lock)
|
|||
struct pin_cookie cookie = NIL_COOKIE;
|
||||
unsigned long flags;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return cookie;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
cookie = __lock_pin_lock(lock);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -5096,13 +5121,13 @@ void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
|
|||
{
|
||||
unsigned long flags;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__lock_repin_lock(lock, cookie);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -5113,13 +5138,13 @@ void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
|
|||
{
|
||||
unsigned long flags;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__lock_unpin_lock(lock, cookie);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -5249,15 +5274,12 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip)
|
|||
|
||||
trace_lock_acquired(lock, ip);
|
||||
|
||||
if (unlikely(!lock_stat || !debug_locks))
|
||||
return;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lock_stat || !lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__lock_contended(lock, ip);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
@ -5270,15 +5292,12 @@ void lock_acquired(struct lockdep_map *lock, unsigned long ip)
|
|||
|
||||
trace_lock_contended(lock, ip);
|
||||
|
||||
if (unlikely(!lock_stat || !debug_locks))
|
||||
return;
|
||||
|
||||
if (unlikely(current->lockdep_recursion))
|
||||
if (unlikely(!lock_stat || !lockdep_enabled()))
|
||||
return;
|
||||
|
||||
raw_local_irq_save(flags);
|
||||
check_flags(flags);
|
||||
current->lockdep_recursion++;
|
||||
lockdep_recursion_inc();
|
||||
__lock_acquired(lock, ip);
|
||||
lockdep_recursion_finish();
|
||||
raw_local_irq_restore(flags);
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user