On Mon, Jan 15 2018, Wang Sheng-Hui wrote:

Dear,

Sorry to trouble you.

I'm confused by the following code in bio.c/bio_split:
-------------------------------------
struct bio *bio_split(struct bio *bio, int sectors,
...
	if (bio_flagged(bio, BIO_TRACE_COMPLETION))
		bio_set_flag(bio, BIO_TRACE_COMPLETION);         
...
}
EXPORT_SYMBOL(bio_split);
------------------------------------

I think it maybe flag on the new split set, right?

Goldwyn Rodrigues posted a patch to fix this a couple of
months ago.
Jens - can you apply that?  Do you need it resent?

https://www.mail-archive.com/linux-block@vger.kernel.org/msg16039.html

Thanks,
NeilBrown

Regards,
shenghui