Re: [PATCH v2 4/4] lockdep: Assign a lock_class per gendisk used for wait_for_completion()

[Christoph Hellwig]

The Subject prefix for this should be "block:".

> @@ -945,7 +945,7 @@ int submit_bio_wait(struct bio *bio)
>  {
>  	struct submit_bio_ret ret;
>  
> -	init_completion(&ret.event);
> +	init_completion_with_map(&ret.event, &bio->bi_disk->lockdep_map);

FYI, I have an outstanding patch to simplify this a lot, which
switches this to DECLARE_COMPLETION_ONSTACK.  I can delay this or let
you pick it up with your series, but we'll need a variant of
DECLARE_COMPLETION_ONSTACK with the lockdep annotations.

Patch below for reference:

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