Re: [GIT PULL] Folio patches for 5.18 (MM part)

[David Hildenbrand <david@redhat.com>]

On 21.03.22 17:54, Matthew Wilcox wrote:
> On Mon, Mar 21, 2022 at 04:38:22PM +0100, David Hildenbrand wrote:
>> On 21.03.22 16:31, Matthew Wilcox wrote:
>>>>>> Alex Sierra (10):
>>>>>>       mm: add zone device coherent type memory support
>>>>>>       mm: add device coherent vma selection for memory migration
>>>>>>       mm/gup: fail get_user_pages for LONGTERM dev coherent type
>>>>>>       drm/amdkfd: add SPM support for SVM
>>>>>>       drm/amdkfd: coherent type as sys mem on migration to ram
>>>>>>       lib: test_hmm add ioctl to get zone device type
>>>>>>       lib: test_hmm add module param for zone device type
>>>>>>       lib: add support for device coherent type in test_hmm
>>>>>>       tools: update hmm-test to support device coherent type
>>>>>>       tools: update test_hmm script to support SP config
>>>>>>
>>>>>> Alistair Popple (2):
>>>>>>       mm: remove the vma check in migrate_vma_setup()
>>>>>>       mm/gup: migrate device coherent pages when pinning instead of failing
>>>>>
>>>>> ... I thought DEVICE_COHERENT is still under development?
>>>>>
>>>>
>>>> After verifying that I'm not daydreaming [1] (and realizing that I had
>>>> review comments to some of these patches that have not been resolved
>>>> yet) and also not spotting these change in your changelog above, I
>>>> assume this stuff was included by mistake. NACK to merging
>>>> DEVICE_COHERENT at this point.
>>>>
>>>> [1] https://lkml.kernel.org/r/20220310172633.9151-1-alex.sierra@amd.com
>>>
>>> That patch ("split vm_normal_pages for LRU and non-LRU handling") isn't
>>> included in this pull request.  The patches I have were those sent by
>>> Christoph here:
>>>
>>> https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/
>>>
>>> I can drop any patches that you have objections to, but I don't see
>>> any objections from you to any patches in that list.
>>
>> Well, I was discussing with the original authors about how to proceed.
>>
>> Quoting from:
>>
>> https://lkml.kernel.org/r/1747447c-202d-9195-9d44-57f299be48c4@amd.com
>>
>> "
>> Yes, it should be part of that series. Alex developed it on top of the
>> series for now. But I think eventually it would need to be spliced into it.
> 
> It wasn't clear to me that you were talking about this series.
> 
>> Patch1 would need to go somewhere before the other DEVICE_COHERENT
>> patches (with minor modifications). Patch 2 could be squashed into
>> "tools: add hmm gup test for long term pinned device pages" or go next
>> to it. Patch 3 doesn't have a direct dependency on device-coherent
>> pages. It only mentions them in comments.
>> "
>>
>> I can understand that Christoph included a rebased version in his rework
>> (to keep it working in -next and/or help the original authors?), but to
>> me that doesn't mean that the feature is finally done.
> 
> OK, so you object to the last 12 patches from Alistair and Alex?  And
> you're OK with the preceeding 15 patches from Christoph?  I can put
> together a pull request for that combination.
> 

Yes, I'm only concerned about the new feature (DEVICE_COHERENT),
essentially what is still under discussion in [1] and [2]
  [PATCH v6 00/10] Add MEMORY_DEVICE_COHERENT for coherent device memory
  mapping
  [PATCH v2 0/3] Migrate device coherent pages on get_user_pages()

I think these should be the patches from Alex and Alistair. I'm happy to
see Christoph's ZONE_DEVICE refocunt changes upstream ;)

[1] https://lkml.kernel.org/r/20220201154901.7921-1-alex.sierra@amd.com
[2]
https://lkml.kernel.org/r/cover.0d3c846b1c6c294e055ff7ebe221fab9964c1436.1644207242.git-series.apopple@nvidia.com
-- 
Thanks,

David / dhildenb