Re: [PATCH 7/9] Guard bvec iteration logic v3

[Christoph Hellwig]

>  	if (bio_no_advance_iter(bio))
>  		iter->bi_size -= bytes;
> -	else
> -		bvec_iter_advance(bio->bi_io_vec, iter, bytes);
> +	else {
> +		int err;
> +		err = bvec_iter_advance(bio->bi_io_vec, iter, bytes);
> +		if (unlikely(err))
> +			bio->bi_error = err;
> +	}

I don't think that setting bi_error here is a good idea without actually
completing the bio, which would be a much bigger change.

Maybe leave the error ignored here for now with a fixme comment, and
then we can look into proper error handling in a separate series.