Re: e827091cb1 "block: merge: get the 1st and last bvec via helpers" broken

From: Ming Lei
Date: Sat Mar 12 2016 - 03:49:54 EST

On Sat, Mar 12, 2016 at 3:43 PM, Kent Overstreet
<kent.overstreet@xxxxxxxxx> wrote:
> I don't know exactly how it's broken, but with that patch segment counting is
> broken - I'm seeing blk_rq_map_sg() overrun the end of the sgtable.
> I suggest reverting it for 4.5...

Kent, could you share your test case? I'd like to figure out the root cause.

BTW, I don't object to revert it given it is close to v4.5 release, but I am
curious how it breaks segment couting.

Ming Lei