Merge tag 'v3.7-rc1' into staging/for_v3.8

Linux 3.7-rc1

* tag 'v3.7-rc1': (9579 commits)
  Linux 3.7-rc1
  x86, boot: Explicitly include autoconf.h for hostprogs
  perf: Fix UAPI fallout
  ARM: config: make sure that platforms are ordered by option string
  ARM: config: sort select statements alphanumerically
  UAPI: (Scripted) Disintegrate include/linux/byteorder
  UAPI: (Scripted) Disintegrate include/linux
  UAPI: Unexport linux/blk_types.h
  UAPI: Unexport part of linux/ppp-comp.h
  perf: Handle new rbtree implementation
  procfs: don't need a PATH_MAX allocation to hold a string representation of an int
  vfs: embed struct filename inside of names_cache allocation if possible
  audit: make audit_inode take struct filename
  vfs: make path_openat take a struct filename pointer
  vfs: turn do_path_lookup into wrapper around struct filename variant
  audit: allow audit code to satisfy getname requests from its names_list
  vfs: define struct filename and have getname() return it
  btrfs: Fix compilation with user namespace support enabled
  userns: Fix posix_acl_file_xattr_userns gid conversion
  userns: Properly print bluetooth socket uids
  ...

1 files changed, 39 insertions, 0 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index ea9ee4518c3..7981e5b2350 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2998,6 +2998,42 @@ EXPORT_SYMBOL_GPL(lockdep_init_map);
 
 struct lock_class_key __lockdep_no_validate__;
 
+static int
+print_lock_nested_lock_not_held(struct task_struct *curr,
+				struct held_lock *hlock,
+				unsigned long ip)
+{
+	if (!debug_locks_off())
+		return 0;
+	if (debug_locks_silent)
+		return 0;
+
+	printk("\n");
+	printk("==================================\n");
+	printk("[ BUG: Nested lock was not taken ]\n");
+	print_kernel_ident();
+	printk("----------------------------------\n");
+
+	printk("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr));
+	print_lock(hlock);
+
+	printk("\nbut this task is not holding:\n");
+	printk("%s\n", hlock->nest_lock->name);
+
+	printk("\nstack backtrace:\n");
+	dump_stack();
+
+	printk("\nother info that might help us debug this:\n");
+	lockdep_print_held_locks(curr);
+
+	printk("\nstack backtrace:\n");
+	dump_stack();
+
+	return 0;
+}
+
+static int __lock_is_held(struct lockdep_map *lock);
+
 /*
  * This gets called for every mutex_lock*()/spin_lock*() operation.
  * We maintain the dependency maps and validate the locking attempt:
@@ -3139,6 +3175,9 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	}
 	chain_key = iterate_chain_key(chain_key, id);
 
+	if (nest_lock && !__lock_is_held(nest_lock))
+		return print_lock_nested_lock_not_held(curr, hlock, ip);
+
 	if (!validate_chain(curr, lock, hlock, chain_head, chain_key))
 		return 0;