Re: please revert the UFS HPB support

Martin K. Petersen
2021-10-23T01:54:54Z

Hi Christoph,

> I just noticed the UFS HPB support landed in 5.15, and just as before
> it is completely broken by allocating another request on the same
> device and then reinserting it in the queue. It is bad enough that we
> have to live with blk_insert_cloned_request for dm-mpath, but this is
> too big of an API abuse to make it into a release. We need to drop
> this code ASAP, and I can prepare a patch for that.

The series went through 40 iterations on the list prior to being merged.
I don't recall a better approach to reconcile the HPB model with the
stack being offered during that process?

As much as I don't like HPB, all the major UFS subsystem stakeholders
are behind it. The hardware is shipping and various device stacks
already adopted support for it. At this stage I don't think dropping the
code is a way forward. I am much more in favor of having a productive
discussion about how to go about addressing the problems with the
queuing model...

--
Martin K. Petersen Oracle Linux Engineering