Re: [PATCH 00/10] HMM updates for 5.1

From: Jerome Glisse <jglisse@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	"Felix Kuehling" <Felix.Kuehling@amd.com>,
	"Christian König" <christian.koenig@amd.com>,
	"Ralph Campbell" <rcampbell@nvidia.com>,
	"John Hubbard" <jhubbard@nvidia.com>,
	"Jason Gunthorpe" <jgg@mellanox.com>,
	"Dan Williams" <dan.j.williams@intel.com>,
	"Alex Deucher" <alexander.deucher@amd.com>
Subject: Re: [PATCH 00/10] HMM updates for 5.1
Date: Tue, 19 Mar 2019 13:18:48 -0400	[thread overview]
Message-ID: <20190319171847.GC3656@redhat.com> (raw)
In-Reply-To: <20190319101249.d2076f4bacbef948055ae758@linux-foundation.org>

On Tue, Mar 19, 2019 at 10:12:49AM -0700, Andrew Morton wrote:
> On Tue, 19 Mar 2019 12:58:02 -0400 Jerome Glisse <jglisse@redhat.com> wrote:
> 
> > > So I think I'll throw up my hands, drop them all and shall await
> > > developments :(
> > 
> > What more do you want to see ? I can repost with the ack already given
> > and the improve commit wording on some of the patch. But from user point
> > of view nouveau is already upstream, ODP RDMA depends on this patchset
> > and is posted and i have given link to it. amdgpu is queue up. What more
> > do i need ?
> 
> I guess I can ignore linux-next for a few days.  
> 
> Yes, a resend against mainline with those various updates will be
> helpful.  Please go through the various fixes which we had as well:

Yes i will not forget them and i will try to get more config build
to be sure there is not issue. I need to register a tree with the
rand-config builder but i lack place where i can host a https tree
(i believe this is a requirement).

> 
> mm-hmm-use-reference-counting-for-hmm-struct.patch
> mm-hmm-do-not-erase-snapshot-when-a-range-is-invalidated.patch
> mm-hmm-improve-and-rename-hmm_vma_get_pfns-to-hmm_range_snapshot.patch
> mm-hmm-improve-and-rename-hmm_vma_fault-to-hmm_range_fault.patch
> mm-hmm-improve-driver-api-to-work-and-wait-over-a-range.patch
> mm-hmm-improve-driver-api-to-work-and-wait-over-a-range-fix.patch
> mm-hmm-improve-driver-api-to-work-and-wait-over-a-range-fix-fix.patch
> mm-hmm-add-default-fault-flags-to-avoid-the-need-to-pre-fill-pfns-arrays.patch
> mm-hmm-add-an-helper-function-that-fault-pages-and-map-them-to-a-device.patch
> mm-hmm-support-hugetlbfs-snap-shoting-faulting-and-dma-mapping.patch
> mm-hmm-allow-to-mirror-vma-of-a-file-on-a-dax-backed-filesystem.patch
> mm-hmm-allow-to-mirror-vma-of-a-file-on-a-dax-backed-filesystem-fix.patch
> mm-hmm-allow-to-mirror-vma-of-a-file-on-a-dax-backed-filesystem-fix-2.patch
> mm-hmm-add-helpers-for-driver-to-safely-take-the-mmap_sem.patch
> 
> Also, the discussion regarding [07/10] is substantial and is ongoing so
> please let's push along wth that.

I can move it as last patch in the serie but it is needed for ODP RDMA
convertion too. Otherwise i will just move that code into the ODP RDMA
code and will have to move it again into HMM code once i am done with
the nouveau changes and in the meantime i expect other driver will want
to use this 2 helpers too.

> 
> What is the review/discussion status of "[PATCH 09/10] mm/hmm: allow to
> mirror vma of a file on a DAX backed filesystem"?

I explained that this is needed for the ODP RDMA convertion as ODP RDMA
does supported DAX today and thus i can not push that convertion without
that support as otherwise i would regress RDMA ODP.

Also this is to be use by nouveau which is upstream and there is no
reasons to not support vma that happens to be mmap of a file on a file-
system that is using a DAX block device.

I do not think Dan had any comment code wise, i think he was complaining
about the wording of the commit not being clear and i proposed an updated
wording that he seemed to like.

Cheers,
Jérôme