From 3ac7fe5a4aab409bd5674d0b070bce97f9d20872 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 30 Apr 2008 00:55:01 -0700 Subject: infrastructure to debug (dynamic) objects We can see an ever repeating problem pattern with objects of any kind in the kernel: 1) freeing of active objects 2) reinitialization of active objects Both problems can be hard to debug because the crash happens at a point where we have no chance to decode the root cause anymore. One problem spot are kernel timers, where the detection of the problem often happens in interrupt context and usually causes the machine to panic. While working on a timer related bug report I had to hack specialized code into the timer subsystem to get a reasonable hint for the root cause. This debug hack was fine for temporary use, but far from a mergeable solution due to the intrusiveness into the timer code. The code further lacked the ability to detect and report the root cause instantly and keep the system operational. Keeping the system operational is important to get hold of the debug information without special debugging aids like serial consoles and special knowledge of the bug reporter. The problems described above are not restricted to timers, but timers tend to expose it usually in a full system crash. Other objects are less explosive, but the symptoms caused by such mistakes can be even harder to debug. Instead of creating specialized debugging code for the timer subsystem a generic infrastructure is created which allows developers to verify their code and provides an easy to enable debug facility for users in case of trouble. The debugobjects core code keeps track of operations on static and dynamic objects by inserting them into a hashed list and sanity checking them on object operations and provides additional checks whenever kernel memory is freed. The tracked object operations are: - initializing an object - adding an object to a subsystem list - deleting an object from a subsystem list Each operation is sanity checked before the operation is executed and the subsystem specific code can provide a fixup function which allows to prevent the damage of the operation. When the sanity check triggers a warning message and a stack trace is printed. The list of operations can be extended if the need arises. For now it's limited to the requirements of the first user (timers). The core code enqueues the objects into hash buckets. The hash index is generated from the address of the object to simplify the lookup for the check on kfree/vfree. Each bucket has it's own spinlock to avoid contention on a global lock. The debug code can be compiled in without being active. The runtime overhead is minimal and could be optimized by asm alternatives. A kernel command line option enables the debugging code. Thanks to Ingo Molnar for review, suggestions and cleanup patches. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Cc: Greg KH Cc: Randy Dunlap Cc: Kay Sievers Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/debugobjects.h | 90 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 include/linux/debugobjects.h (limited to 'include/linux/debugobjects.h') diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h new file mode 100644 index 000000000000..8c243aaa86a7 --- /dev/null +++ b/include/linux/debugobjects.h @@ -0,0 +1,90 @@ +#ifndef _LINUX_DEBUGOBJECTS_H +#define _LINUX_DEBUGOBJECTS_H + +#include +#include + +enum debug_obj_state { + ODEBUG_STATE_NONE, + ODEBUG_STATE_INIT, + ODEBUG_STATE_INACTIVE, + ODEBUG_STATE_ACTIVE, + ODEBUG_STATE_DESTROYED, + ODEBUG_STATE_NOTAVAILABLE, + ODEBUG_STATE_MAX, +}; + +struct debug_obj_descr; + +/** + * struct debug_obj - representaion of an tracked object + * @node: hlist node to link the object into the tracker list + * @state: tracked object state + * @object: pointer to the real object + * @descr: pointer to an object type specific debug description structure + */ +struct debug_obj { + struct hlist_node node; + enum debug_obj_state state; + void *object; + struct debug_obj_descr *descr; +}; + +/** + * struct debug_obj_descr - object type specific debug description structure + * @name: name of the object typee + * @fixup_init: fixup function, which is called when the init check + * fails + * @fixup_activate: fixup function, which is called when the activate check + * fails + * @fixup_destroy: fixup function, which is called when the destroy check + * fails + * @fixup_free: fixup function, which is called when the free check + * fails + */ +struct debug_obj_descr { + const char *name; + + int (*fixup_init) (void *addr, enum debug_obj_state state); + int (*fixup_activate) (void *addr, enum debug_obj_state state); + int (*fixup_destroy) (void *addr, enum debug_obj_state state); + int (*fixup_free) (void *addr, enum debug_obj_state state); +}; + +#ifdef CONFIG_DEBUG_OBJECTS +extern void debug_object_init (void *addr, struct debug_obj_descr *descr); +extern void +debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr); +extern void debug_object_activate (void *addr, struct debug_obj_descr *descr); +extern void debug_object_deactivate(void *addr, struct debug_obj_descr *descr); +extern void debug_object_destroy (void *addr, struct debug_obj_descr *descr); +extern void debug_object_free (void *addr, struct debug_obj_descr *descr); + +extern void debug_objects_early_init(void); +extern void debug_objects_mem_init(void); +#else +static inline void +debug_object_init (void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_activate (void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_deactivate(void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_destroy (void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_free (void *addr, struct debug_obj_descr *descr) { } + +static inline void debug_objects_early_init(void) { } +static inline void debug_objects_mem_init(void) { } +#endif + +#ifdef CONFIG_DEBUG_OBJECTS_FREE +extern void debug_check_no_obj_freed(const void *address, unsigned long size); +#else +static inline void +debug_check_no_obj_freed(const void *address, unsigned long size) { } +#endif + +#endif -- cgit v1.2.3 From a5d8e467f83f6672104f276223a88e3b50cbd375 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Sat, 17 Apr 2010 08:48:38 -0400 Subject: Debugobjects transition check Implement a basic state machine checker in the debugobjects. This state machine checker detects races and inconsistencies within the "active" life of a debugobject. The checker only keeps track of the current state; all the state machine logic is kept at the object instance level. The checker works by adding a supplementary "unsigned int astate" field to the debug_obj structure. It keeps track of the current "active state" of the object. The only constraints that are imposed on the states by the debugobjects system is that: - activation of an object sets the current active state to 0, - deactivation of an object expects the current active state to be 0. For the rest of the states, the state mapping is determined by the specific object instance. Therefore, the logic keeping track of the state machine is within the specialized instance, without any need to know about it at the debugobject level. The current object active state is changed by calling: debug_object_active_state(addr, descr, expect, next) where "expect" is the expected state and "next" is the next state to move to if the expected state is found. A warning is generated if the expected is not found. Signed-off-by: Mathieu Desnoyers Reviewed-by: Thomas Gleixner Acked-by: David S. Miller CC: "Paul E. McKenney" CC: akpm@linux-foundation.org CC: mingo@elte.hu CC: laijs@cn.fujitsu.com CC: dipankar@in.ibm.com CC: josh@joshtriplett.org CC: dvhltc@us.ibm.com CC: niv@us.ibm.com CC: peterz@infradead.org CC: rostedt@goodmis.org CC: Valdis.Kletnieks@vt.edu CC: dhowells@redhat.com CC: eric.dumazet@gmail.com CC: Alexey Dobriyan Signed-off-by: Paul E. McKenney --- include/linux/debugobjects.h | 11 +++++++++ lib/debugobjects.c | 59 +++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 67 insertions(+), 3 deletions(-) (limited to 'include/linux/debugobjects.h') diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h index 8c243aaa86a7..597692f1fc8d 100644 --- a/include/linux/debugobjects.h +++ b/include/linux/debugobjects.h @@ -20,12 +20,14 @@ struct debug_obj_descr; * struct debug_obj - representaion of an tracked object * @node: hlist node to link the object into the tracker list * @state: tracked object state + * @astate: current active state * @object: pointer to the real object * @descr: pointer to an object type specific debug description structure */ struct debug_obj { struct hlist_node node; enum debug_obj_state state; + unsigned int astate; void *object; struct debug_obj_descr *descr; }; @@ -60,6 +62,15 @@ extern void debug_object_deactivate(void *addr, struct debug_obj_descr *descr); extern void debug_object_destroy (void *addr, struct debug_obj_descr *descr); extern void debug_object_free (void *addr, struct debug_obj_descr *descr); +/* + * Active state: + * - Set at 0 upon initialization. + * - Must return to 0 before deactivation. + */ +extern void +debug_object_active_state(void *addr, struct debug_obj_descr *descr, + unsigned int expect, unsigned int next); + extern void debug_objects_early_init(void); extern void debug_objects_mem_init(void); #else diff --git a/lib/debugobjects.c b/lib/debugobjects.c index b862b30369ff..076464fd2072 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -141,6 +141,7 @@ alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) obj->object = addr; obj->descr = descr; obj->state = ODEBUG_STATE_NONE; + obj->astate = 0; hlist_del(&obj->node); hlist_add_head(&obj->node, &b->list); @@ -252,8 +253,10 @@ static void debug_print_object(struct debug_obj *obj, char *msg) if (limit < 5 && obj->descr != descr_test) { limit++; - WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg, - obj_states[obj->state], obj->descr->name); + WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) " + "object type: %s\n", + msg, obj_states[obj->state], obj->astate, + obj->descr->name); } debug_objects_warnings++; } @@ -447,7 +450,10 @@ void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: case ODEBUG_STATE_ACTIVE: - obj->state = ODEBUG_STATE_INACTIVE; + if (!obj->astate) + obj->state = ODEBUG_STATE_INACTIVE; + else + debug_print_object(obj, "deactivate"); break; case ODEBUG_STATE_DESTROYED: @@ -553,6 +559,53 @@ out_unlock: raw_spin_unlock_irqrestore(&db->lock, flags); } +/** + * debug_object_active_state - debug checks object usage state machine + * @addr: address of the object + * @descr: pointer to an object specific debug description structure + * @expect: expected state + * @next: state to move to if expected state is found + */ +void +debug_object_active_state(void *addr, struct debug_obj_descr *descr, + unsigned int expect, unsigned int next) +{ + struct debug_bucket *db; + struct debug_obj *obj; + unsigned long flags; + + if (!debug_objects_enabled) + return; + + db = get_bucket((unsigned long) addr); + + raw_spin_lock_irqsave(&db->lock, flags); + + obj = lookup_object(addr, db); + if (obj) { + switch (obj->state) { + case ODEBUG_STATE_ACTIVE: + if (obj->astate == expect) + obj->astate = next; + else + debug_print_object(obj, "active_state"); + break; + + default: + debug_print_object(obj, "active_state"); + break; + } + } else { + struct debug_obj o = { .object = addr, + .state = ODEBUG_STATE_NOTAVAILABLE, + .descr = descr }; + + debug_print_object(&o, "active_state"); + } + + raw_spin_unlock_irqrestore(&db->lock, flags); +} + #ifdef CONFIG_DEBUG_OBJECTS_FREE static void __debug_check_no_obj_freed(const void *address, unsigned long size) { -- cgit v1.2.3 From 997772884036e6e121de39322179989154437d9f Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Mon, 7 Mar 2011 09:58:33 +0100 Subject: debugobjects: Add hint for better object identification In complex subsystems like mac80211 structures can contain several timers and work structs, so identifying a specific instance from the call trace and object type output of debugobjects can be hard. Allow the subsystems which support debugobjects to provide a hint function. This function returns a pointer to a kernel address (preferrably the objects callback function) which is printed along with the debugobjects type. Add hint methods for timer_list, work_struct and hrtimer. [ tglx: Massaged changelog, made it compile ] Signed-off-by: Stanislaw Gruszka LKML-Reference: <20110307085809.GA9334@redhat.com> Signed-off-by: Thomas Gleixner --- include/linux/debugobjects.h | 5 ++++- kernel/hrtimer.c | 6 ++++++ kernel/timer.c | 6 ++++++ kernel/workqueue.c | 6 ++++++ lib/debugobjects.c | 9 ++++++--- 5 files changed, 28 insertions(+), 4 deletions(-) (limited to 'include/linux/debugobjects.h') diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h index 597692f1fc8d..65970b811e22 100644 --- a/include/linux/debugobjects.h +++ b/include/linux/debugobjects.h @@ -34,7 +34,10 @@ struct debug_obj { /** * struct debug_obj_descr - object type specific debug description structure + * * @name: name of the object typee + * @debug_hint: function returning address, which have associated + * kernel symbol, to allow identify the object * @fixup_init: fixup function, which is called when the init check * fails * @fixup_activate: fixup function, which is called when the activate check @@ -46,7 +49,7 @@ struct debug_obj { */ struct debug_obj_descr { const char *name; - + void *(*debug_hint) (void *addr); int (*fixup_init) (void *addr, enum debug_obj_state state); int (*fixup_activate) (void *addr, enum debug_obj_state state); int (*fixup_destroy) (void *addr, enum debug_obj_state state); diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 0c8d7c048615..e38f5a073d01 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -334,6 +334,11 @@ EXPORT_SYMBOL_GPL(ktime_add_safe); static struct debug_obj_descr hrtimer_debug_descr; +static void *hrtimer_debug_hint(void *addr) +{ + return ((struct hrtimer *) addr)->function; +} + /* * fixup_init is called when: * - an active object is initialized @@ -393,6 +398,7 @@ static int hrtimer_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr hrtimer_debug_descr = { .name = "hrtimer", + .debug_hint = hrtimer_debug_hint, .fixup_init = hrtimer_fixup_init, .fixup_activate = hrtimer_fixup_activate, .fixup_free = hrtimer_fixup_free, diff --git a/kernel/timer.c b/kernel/timer.c index d6459923d245..33a67925d900 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -404,6 +404,11 @@ static void timer_stats_account_timer(struct timer_list *timer) {} static struct debug_obj_descr timer_debug_descr; +static void *timer_debug_hint(void *addr) +{ + return ((struct timer_list *) addr)->function; +} + /* * fixup_init is called when: * - an active object is initialized @@ -477,6 +482,7 @@ static int timer_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr timer_debug_descr = { .name = "timer_list", + .debug_hint = timer_debug_hint, .fixup_init = timer_fixup_init, .fixup_activate = timer_fixup_activate, .fixup_free = timer_fixup_free, diff --git a/kernel/workqueue.c b/kernel/workqueue.c index ee6578b578ad..b5fe4c00eb3c 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -316,6 +316,11 @@ static inline int __next_wq_cpu(int cpu, const struct cpumask *mask, static struct debug_obj_descr work_debug_descr; +static void *work_debug_hint(void *addr) +{ + return ((struct work_struct *) addr)->func; +} + /* * fixup_init is called when: * - an active object is initialized @@ -387,6 +392,7 @@ static int work_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr work_debug_descr = { .name = "work_struct", + .debug_hint = work_debug_hint, .fixup_init = work_fixup_init, .fixup_activate = work_fixup_activate, .fixup_free = work_fixup_free, diff --git a/lib/debugobjects.c b/lib/debugobjects.c index deebcc57d4e6..9d86e45086f5 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -249,14 +249,17 @@ static struct debug_bucket *get_bucket(unsigned long addr) static void debug_print_object(struct debug_obj *obj, char *msg) { + struct debug_obj_descr *descr = obj->descr; static int limit; - if (limit < 5 && obj->descr != descr_test) { + if (limit < 5 && descr != descr_test) { + void *hint = descr->debug_hint ? + descr->debug_hint(obj->object) : NULL; limit++; WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) " - "object type: %s\n", + "object type: %s hint: %pS\n", msg, obj_states[obj->state], obj->astate, - obj->descr->name); + descr->name, hint); } debug_objects_warnings++; } -- cgit v1.2.3 From b84d435cc228e87951f3bbabf6cc4a5f25d5fb16 Mon Sep 17 00:00:00 2001 From: Christine Chan Date: Mon, 7 Nov 2011 19:48:27 -0800 Subject: debugobjects: Extend to assert that an object is initialized Calling del_timer_sync() on an uninitialized timer leads to a never ending loop in lock_timer_base() that spins checking for a non-NULL timer base. Add an assertion to debugobjects to catch usage of uninitialized objects so that we can initialize timers in the del_timer_sync() path before it calls lock_timer_base(). [ sboyd@codeaurora.org: Clarify commit message ] Signed-off-by: Christine Chan Signed-off-by: Stephen Boyd Cc: John Stultz Link: http://lkml.kernel.org/r/1320724108-20788-3-git-send-email-sboyd@codeaurora.org Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner --- Documentation/DocBook/debugobjects.tmpl | 50 +++++++++++++++++++++++++++++++++ include/linux/debugobjects.h | 6 ++++ lib/debugobjects.c | 38 +++++++++++++++++++++++++ 3 files changed, 94 insertions(+) (limited to 'include/linux/debugobjects.h') diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl index 08ff908aa7a2..24979f691e3e 100644 --- a/Documentation/DocBook/debugobjects.tmpl +++ b/Documentation/DocBook/debugobjects.tmpl @@ -96,6 +96,7 @@ debug_object_deactivate debug_object_destroy debug_object_free + debug_object_assert_init Each of these functions takes the address of the real object and a pointer to the object type specific debug description @@ -273,6 +274,26 @@ debug checks. + + + debug_object_assert_init + + This function is called to assert that an object has been + initialized. + + + When the real object is not tracked by debugobjects, it calls + fixup_assert_init of the object type description structure + provided by the caller, with the hardcoded object state + ODEBUG_NOT_AVAILABLE. The fixup function can correct the problem + by calling debug_object_init and other specific initializing + functions. + + + When the real object is already tracked by debugobjects it is + ignored. + + Fixup functions @@ -381,6 +402,35 @@ statistics. + + fixup_assert_init + + This function is called from the debug code whenever a problem + in debug_object_assert_init is detected. + + + Called from debug_object_assert_init() with a hardcoded state + ODEBUG_STATE_NOTAVAILABLE when the object is not found in the + debug bucket. + + + The function returns 1 when the fixup was successful, + otherwise 0. The return value is used to update the + statistics. + + + Note, this function should make sure debug_object_init() is + called before returning. + + + The handling of statically initialized objects is a special + case. The fixup function should check if this is a legitimate + case of a statically initialized object or not. In this case only + debug_object_init() should be called to make the object known to + the tracker. Then the function should return 0 because this is not + a real fixup. + + Known Bugs And Assumptions diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h index 65970b811e22..0e5f5785d9f2 100644 --- a/include/linux/debugobjects.h +++ b/include/linux/debugobjects.h @@ -46,6 +46,8 @@ struct debug_obj { * fails * @fixup_free: fixup function, which is called when the free check * fails + * @fixup_assert_init: fixup function, which is called when the assert_init + * check fails */ struct debug_obj_descr { const char *name; @@ -54,6 +56,7 @@ struct debug_obj_descr { int (*fixup_activate) (void *addr, enum debug_obj_state state); int (*fixup_destroy) (void *addr, enum debug_obj_state state); int (*fixup_free) (void *addr, enum debug_obj_state state); + int (*fixup_assert_init)(void *addr, enum debug_obj_state state); }; #ifdef CONFIG_DEBUG_OBJECTS @@ -64,6 +67,7 @@ extern void debug_object_activate (void *addr, struct debug_obj_descr *descr); extern void debug_object_deactivate(void *addr, struct debug_obj_descr *descr); extern void debug_object_destroy (void *addr, struct debug_obj_descr *descr); extern void debug_object_free (void *addr, struct debug_obj_descr *descr); +extern void debug_object_assert_init(void *addr, struct debug_obj_descr *descr); /* * Active state: @@ -89,6 +93,8 @@ static inline void debug_object_destroy (void *addr, struct debug_obj_descr *descr) { } static inline void debug_object_free (void *addr, struct debug_obj_descr *descr) { } +static inline void +debug_object_assert_init(void *addr, struct debug_obj_descr *descr) { } static inline void debug_objects_early_init(void) { } static inline void debug_objects_mem_init(void) { } diff --git a/lib/debugobjects.c b/lib/debugobjects.c index b7a530504b38..77cb245f8e7b 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -570,6 +570,44 @@ out_unlock: raw_spin_unlock_irqrestore(&db->lock, flags); } +/** + * debug_object_assert_init - debug checks when object should be init-ed + * @addr: address of the object + * @descr: pointer to an object specific debug description structure + */ +void debug_object_assert_init(void *addr, struct debug_obj_descr *descr) +{ + struct debug_bucket *db; + struct debug_obj *obj; + unsigned long flags; + + if (!debug_objects_enabled) + return; + + db = get_bucket((unsigned long) addr); + + raw_spin_lock_irqsave(&db->lock, flags); + + obj = lookup_object(addr, db); + if (!obj) { + struct debug_obj o = { .object = addr, + .state = ODEBUG_STATE_NOTAVAILABLE, + .descr = descr }; + + raw_spin_unlock_irqrestore(&db->lock, flags); + /* + * Maybe the object is static. Let the type specific + * code decide what to do. + */ + if (debug_object_fixup(descr->fixup_assert_init, addr, + ODEBUG_STATE_NOTAVAILABLE)) + debug_print_object(&o, "assert_init"); + return; + } + + raw_spin_unlock_irqrestore(&db->lock, flags); +} + /** * debug_object_active_state - debug checks object usage state machine * @addr: address of the object -- cgit v1.2.3 From b778ae25366e6f3891fe51306f56a3bca211975d Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 23 Apr 2013 12:51:11 -0700 Subject: debugobjects: Make debug_object_activate() return status In order to better respond to things like duplicate invocations of call_rcu(), RCU needs to see the status of a call to debug_object_activate(). This would allow RCU to leak the callback in order to avoid adding freelist-reuse mischief to the duplicate invoations. This commit therefore makes debug_object_activate() return status, zero for success and -EINVAL for failure. Signed-off-by: Paul E. McKenney Cc: Mathieu Desnoyers Cc: Sedat Dilek Cc: Davidlohr Bueso Cc: Rik van Riel Cc: Thomas Gleixner Cc: Linus Torvalds Tested-by: Sedat Dilek Reviewed-by: Josh Triplett --- include/linux/debugobjects.h | 6 +++--- lib/debugobjects.c | 20 ++++++++++++++------ 2 files changed, 17 insertions(+), 9 deletions(-) (limited to 'include/linux/debugobjects.h') diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h index 0e5f5785d9f2..98ffcbd4888e 100644 --- a/include/linux/debugobjects.h +++ b/include/linux/debugobjects.h @@ -63,7 +63,7 @@ struct debug_obj_descr { extern void debug_object_init (void *addr, struct debug_obj_descr *descr); extern void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr); -extern void debug_object_activate (void *addr, struct debug_obj_descr *descr); +extern int debug_object_activate (void *addr, struct debug_obj_descr *descr); extern void debug_object_deactivate(void *addr, struct debug_obj_descr *descr); extern void debug_object_destroy (void *addr, struct debug_obj_descr *descr); extern void debug_object_free (void *addr, struct debug_obj_descr *descr); @@ -85,8 +85,8 @@ static inline void debug_object_init (void *addr, struct debug_obj_descr *descr) { } static inline void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) { } -static inline void -debug_object_activate (void *addr, struct debug_obj_descr *descr) { } +static inline int +debug_object_activate (void *addr, struct debug_obj_descr *descr) { return 0; } static inline void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) { } static inline void diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 37061ede8b81..bf2c8b1043d8 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -381,19 +381,21 @@ void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) * debug_object_activate - debug checks when an object is activated * @addr: address of the object * @descr: pointer to an object specific debug description structure + * Returns 0 for success, -EINVAL for check failed. */ -void debug_object_activate(void *addr, struct debug_obj_descr *descr) +int debug_object_activate(void *addr, struct debug_obj_descr *descr) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; + int ret; struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; if (!debug_objects_enabled) - return; + return 0; db = get_bucket((unsigned long) addr); @@ -405,23 +407,26 @@ void debug_object_activate(void *addr, struct debug_obj_descr *descr) case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: obj->state = ODEBUG_STATE_ACTIVE; + ret = 0; break; case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "activate"); state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); - debug_object_fixup(descr->fixup_activate, addr, state); - return; + ret = debug_object_fixup(descr->fixup_activate, addr, state); + return ret ? -EINVAL : 0; case ODEBUG_STATE_DESTROYED: debug_print_object(obj, "activate"); + ret = -EINVAL; break; default: + ret = 0; break; } raw_spin_unlock_irqrestore(&db->lock, flags); - return; + return ret; } raw_spin_unlock_irqrestore(&db->lock, flags); @@ -431,8 +436,11 @@ void debug_object_activate(void *addr, struct debug_obj_descr *descr) * true or not. */ if (debug_object_fixup(descr->fixup_activate, addr, - ODEBUG_STATE_NOTAVAILABLE)) + ODEBUG_STATE_NOTAVAILABLE)) { debug_print_object(&o, "activate"); + return -EINVAL; + } + return 0; } /** -- cgit v1.2.3