Re: [PATCH] block: fix disordered IO in the case recursive split

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Thu, Aug 21, 2025 at 03:47:06PM +0800, Yu Kuai wrote:
> +	if (current->bio_list) {
> +		if (bio_flagged(bio, BIO_CHAIN))
> +			bio_list_add_head(&current->bio_list[0], bio);
> +		else
> +			bio_list_add(&current->bio_list[0], bio);
> +	} else if (!bdev_test_flag(bio->bi_bdev, BD_HAS_SUBMIT_BIO)) {

This breaks all the code the already chains the right way around,
and there's quite a bit of that (speaking as someone who created a few
instances).

So instead fix your submitter to chain the right way instead.