[linux-yocto] [PATCH] kmemleak: change the lock of kmemleak_object to raw_spinlock_t
zhe.he at windriver.com
zhe.he at windriver.com
Fri May 10 01:32:08 PDT 2019
From: Liu Haitao <haitao.liu at windriver.com>
The following call trace would be triggered as kmemleak is running.
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:974
in_atomic(): 1, irqs_disabled(): 1, pid: 2401, name: kmemleak
Preemption disabled at:
[<ffffffff905f6271>] scan_block+0x31/0x120
CPU: 12 PID: 247 Comm: kmemleak Tainted: G W 4.18.20-rt8-yocto-preempt-rt #1
Hardware name: Intel Corp. Harcuvar/Server, BIOS HAVLCRB1.X64.0015.D62.1708310404 08/31/2017
Call Trace:
dump_stack+0x4f/0x6a
? scan_block+0x31/0x120
___might_sleep.cold.18+0xca/0xdb
rt_spin_lock+0x37/0x60
scan_block+0x9d/0x120
scan_gray_list+0x108/0x170
kmemleak_scan+0x230/0x460
kmemleak_scan_thread+0x9d/0xba
kthread+0x12c/0x150
? kmemleak_scan.cold.19+0x1b/0x1b
? kthread_flush_work_fn+0x20/0x20
ret_from_fork+0x35/0x40
The commit(41cf9e5bb14fbbf782e4191b792d3b898c130469) changed the kmemleak_lock
to raw spinlock. However the kmemleak_object->lock is held after the
kmemleak_lock is held in scan_block().
scan_block()
|
raw_spin_lock_irqsave(&kmemleak_lock, flags)
|
spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
In this case, the object->lock is implemented by mutex in RT. It could casue a sleeping problem.
Fixes: 41cf9e5bb14f ("kmemleak: Turn kmemleak_lock to raw spinlock on RT")
Signed-off-by: Liu Haitao <haitao.liu at windriver.com>
Rebase on top of latest RT code
Signed-off-by: He Zhe <zhe.he at windriver.com>
---
This is just for v5.0 preempt-rt branches.
kmemleak_lock is going to be changed to rcu in upstream, which would get rid of
this error at the same time. But it'll cost some time. So for this moment it's
worthing merging this patch.
mm/kmemleak.c | 72 +++++++++++++++++++++++++++++------------------------------
1 file changed, 36 insertions(+), 36 deletions(-)
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index b4036ff..00a7941 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -148,7 +148,7 @@ struct kmemleak_scan_area {
* (use_count) and freed using the RCU mechanism.
*/
struct kmemleak_object {
- spinlock_t lock;
+ raw_spinlock_t lock;
unsigned int flags; /* object status flags */
struct list_head object_list;
struct list_head gray_list;
@@ -586,7 +586,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
INIT_LIST_HEAD(&object->object_list);
INIT_LIST_HEAD(&object->gray_list);
INIT_HLIST_HEAD(&object->area_list);
- spin_lock_init(&object->lock);
+ raw_spin_lock_init(&object->lock);
atomic_set(&object->use_count, 1);
object->flags = OBJECT_ALLOCATED;
object->pointer = ptr;
@@ -668,9 +668,9 @@ static void __delete_object(struct kmemleak_object *object)
* Locking here also ensures that the corresponding memory block
* cannot be freed when it is being scanned.
*/
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
object->flags &= ~OBJECT_ALLOCATED;
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
}
@@ -742,9 +742,9 @@ static void paint_it(struct kmemleak_object *object, int color)
{
unsigned long flags;
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
__paint_it(object, color);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
static void paint_ptr(unsigned long ptr, int color)
@@ -804,7 +804,7 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
goto out;
}
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if (size == SIZE_MAX) {
size = object->pointer + object->size - ptr;
} else if (ptr + size > object->pointer + object->size) {
@@ -820,7 +820,7 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
hlist_add_head(&area->node, &object->area_list);
out_unlock:
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
out:
put_object(object);
}
@@ -843,9 +843,9 @@ static void object_set_excess_ref(unsigned long ptr, unsigned long excess_ref)
return;
}
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
object->excess_ref = excess_ref;
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
}
@@ -865,9 +865,9 @@ static void object_no_scan(unsigned long ptr)
return;
}
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
object->flags |= OBJECT_NO_SCAN;
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
}
@@ -928,11 +928,11 @@ static void early_alloc(struct early_log *log)
log->min_count, GFP_ATOMIC);
if (!object)
goto out;
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
for (i = 0; i < log->trace_len; i++)
object->trace[i] = log->trace[i];
object->trace_len = log->trace_len;
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
out:
rcu_read_unlock();
}
@@ -1122,9 +1122,9 @@ void __ref kmemleak_update_trace(const void *ptr)
return;
}
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
object->trace_len = __save_stack_trace(object->trace);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
}
@@ -1372,7 +1372,7 @@ static void scan_block(void *_start, void *_end,
* previously acquired in scan_object(). These locks are
* enclosed by scan_mutex.
*/
- spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
/* only pass surplus references (object already gray) */
if (color_gray(object)) {
excess_ref = object->excess_ref;
@@ -1381,7 +1381,7 @@ static void scan_block(void *_start, void *_end,
excess_ref = 0;
update_refs(object);
}
- spin_unlock(&object->lock);
+ raw_spin_unlock(&object->lock);
if (excess_ref) {
object = lookup_object(excess_ref, 0);
@@ -1390,9 +1390,9 @@ static void scan_block(void *_start, void *_end,
if (object == scanned)
/* circular reference, ignore */
continue;
- spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
+ raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
update_refs(object);
- spin_unlock(&object->lock);
+ raw_spin_unlock(&object->lock);
}
}
raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
@@ -1426,7 +1426,7 @@ static void scan_object(struct kmemleak_object *object)
* Once the object->lock is acquired, the corresponding memory block
* cannot be freed (the same lock is acquired in delete_object).
*/
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if (object->flags & OBJECT_NO_SCAN)
goto out;
if (!(object->flags & OBJECT_ALLOCATED))
@@ -1445,9 +1445,9 @@ static void scan_object(struct kmemleak_object *object)
if (start >= end)
break;
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
cond_resched();
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
} while (object->flags & OBJECT_ALLOCATED);
} else
hlist_for_each_entry(area, &object->area_list, node)
@@ -1455,7 +1455,7 @@ static void scan_object(struct kmemleak_object *object)
(void *)(area->start + area->size),
object);
out:
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
/*
@@ -1508,7 +1508,7 @@ static void kmemleak_scan(void)
/* prepare the kmemleak_object's */
rcu_read_lock();
list_for_each_entry_rcu(object, &object_list, object_list) {
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
#ifdef DEBUG
/*
* With a few exceptions there should be a maximum of
@@ -1525,7 +1525,7 @@ static void kmemleak_scan(void)
if (color_gray(object) && get_object(object))
list_add_tail(&object->gray_list, &gray_list);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
rcu_read_unlock();
@@ -1598,14 +1598,14 @@ static void kmemleak_scan(void)
*/
rcu_read_lock();
list_for_each_entry_rcu(object, &object_list, object_list) {
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if (color_white(object) && (object->flags & OBJECT_ALLOCATED)
&& update_checksum(object) && get_object(object)) {
/* color it gray temporarily */
object->count = object->min_count;
list_add_tail(&object->gray_list, &gray_list);
}
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
rcu_read_unlock();
@@ -1625,7 +1625,7 @@ static void kmemleak_scan(void)
*/
rcu_read_lock();
list_for_each_entry_rcu(object, &object_list, object_list) {
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if (unreferenced_object(object) &&
!(object->flags & OBJECT_REPORTED)) {
object->flags |= OBJECT_REPORTED;
@@ -1635,7 +1635,7 @@ static void kmemleak_scan(void)
new_leaks++;
}
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
rcu_read_unlock();
@@ -1787,10 +1787,10 @@ static int kmemleak_seq_show(struct seq_file *seq, void *v)
struct kmemleak_object *object = v;
unsigned long flags;
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if ((object->flags & OBJECT_REPORTED) && unreferenced_object(object))
print_unreferenced(seq, object);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
return 0;
}
@@ -1820,9 +1820,9 @@ static int dump_str_object_info(const char *str)
return -EINVAL;
}
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
dump_object_info(object);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
return 0;
@@ -1841,11 +1841,11 @@ static void kmemleak_clear(void)
rcu_read_lock();
list_for_each_entry_rcu(object, &object_list, object_list) {
- spin_lock_irqsave(&object->lock, flags);
+ raw_spin_lock_irqsave(&object->lock, flags);
if ((object->flags & OBJECT_REPORTED) &&
unreferenced_object(object))
__paint_it(object, KMEMLEAK_GREY);
- spin_unlock_irqrestore(&object->lock, flags);
+ raw_spin_unlock_irqrestore(&object->lock, flags);
}
rcu_read_unlock();
--
2.7.4
More information about the linux-yocto
mailing list