On 02/29/2016 12:25 PM, Ingo Molnar wrote:
>
> * Ingo Molnar <mi...@kernel.org> wrote:
>
>>
>> * Andrew Morton <a...@linux-foundation.org> wrote:
>>
>>> On Tue, 9 Feb 2016 12:12:29 +0100 Ingo Molnar <mi...@kernel.org> wrote:
>>>
>>>>> The conceptual problem is that if some piece of code does
>>>>> spin_lock_init() or
>>>>> DEFINE_SPINLOCK(), that lock isn't necessarily initialized yet.
>>>>
>>>> The conceptual problem is that the data structures are not build time
>>>> initialized
>>>> - but the hlist conversion patch solves that problem nicely!
>>>>
>>>> So I'm a happy camper.
>>>
>>> OK, so the below has been in -next for nearly a week, no issues. We
>>> should get this into 4.5 to fix the CONFIG_UBSAN_ALIGNMENT issue.
>>
>> So I think this patch broke liblockdep:
>>
>> triton:~/tip/tools/lib/lockdep>
>>
>> In file included from lockdep.c:2:0:
>> ../../../kernel/locking/lockdep.c: In function ‘look_up_lock_class’:
>> ../../../kernel/locking/lockdep.c:722:2: warning: implicit declaration of
>> function ‘hlist_for_each_entry_rcu’ [-Wimplicit-function-declaration]
>> hlist_for_each_entry_rcu(class, hash_head, hash_entry) {
>
> The patch below fixes it.
>
> Thanks,
>
> Ingo
>
> tools/lib/lockdep/lockdep.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/tools/lib/lockdep/lockdep.c b/tools/lib/lockdep/lockdep.c
> index f42b7e9aa48f..a0a2e3a266af 100644
> --- a/tools/lib/lockdep/lockdep.c
> +++ b/tools/lib/lockdep/lockdep.c
> @@ -1,2 +1,8 @@
> #include <linux/lockdep.h>
> +
> +/* Trivial API wrappers, we don't (yet) have RCU in user-space: */
> +#define hlist_for_each_entry_rcu hlist_for_each_entry
> +#define hlist_add_head_rcu hlist_add_head
> +#define hlist_del_rcu hlist_del
> +
I think this belongs to tools/lib/lockdep/uinclude/linux/kernel.h
