diff options
| -rw-r--r-- | kernel/lockdep.c | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/kernel/lockdep.c b/kernel/lockdep.c index c4cc5d1acf48..0b497dda6ae5 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -1395,15 +1395,15 @@ print_shortest_lock_dependencies(struct lock_list *leaf, static void print_irq_lock_scenario(struct lock_list *safe_entry, struct lock_list *unsafe_entry, - struct held_lock *prev, - struct held_lock *next) + struct lock_class *prev_class, + struct lock_class *next_class) { struct lock_class *safe_class = safe_entry->class; struct lock_class *unsafe_class = unsafe_entry->class; - struct lock_class *middle_class = hlock_class(prev); + struct lock_class *middle_class = prev_class; if (middle_class == safe_class) - middle_class = hlock_class(next); + middle_class = next_class; /* * A direct locking problem where unsafe_class lock is taken @@ -1499,7 +1499,8 @@ print_bad_irq_dependency(struct task_struct *curr, print_stack_trace(forwards_entry->class->usage_traces + bit2, 1); printk("\nother info that might help us debug this:\n\n"); - print_irq_lock_scenario(backwards_entry, forwards_entry, prev, next); + print_irq_lock_scenario(backwards_entry, forwards_entry, + hlock_class(prev), hlock_class(next)); lockdep_print_held_locks(curr); @@ -2219,6 +2220,10 @@ print_irq_inversion_bug(struct task_struct *curr, struct held_lock *this, int forwards, const char *irqclass) { + struct lock_list *entry = other; + struct lock_list *middle = NULL; + int depth; + if (!debug_locks_off_graph_unlock() || debug_locks_silent) return 0; @@ -2237,6 +2242,25 @@ print_irq_inversion_bug(struct task_struct *curr, printk("\n\nand interrupts could create inverse lock ordering between them.\n\n"); printk("\nother info that might help us debug this:\n"); + + /* Find a middle lock (if one exists) */ + depth = get_lock_depth(other); + do { + if (depth == 0 && (entry != root)) { + printk("lockdep:%s bad path found in chain graph\n", __func__); + break; + } + middle = entry; + entry = get_lock_parent(entry); + depth--; + } while (entry && entry != root && (depth >= 0)); + if (forwards) + print_irq_lock_scenario(root, other, + middle ? middle->class : root->class, other->class); + else + print_irq_lock_scenario(other, root, + middle ? middle->class : other->class, root->class); + lockdep_print_held_locks(curr); printk("\nthe shortest dependencies between 2nd lock and 1st lock:\n"); |