[v2] mm/hmm: A fix and a selftest

[PATCH v2 0/2] mm/hmm: A fix and a selftest

Posted by Dev Jain 1 week ago

Patch 1 fixes a stale warning present from the time when only migration
softleaf entries were supported at the PMD level.

Patch 2 adds some code into hmm-tests.c which exercises the pagemap path
for PMD device-private entries.

---
Applies on mm-unstable (404fb4f38e8f).

Dev Jain (2):
  fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
  selftests/mm/hmm-tests: test pagemap reads of PMD device-private
    entries

 fs/proc/task_mmu.c                     |  1 -
 tools/testing/selftests/mm/hmm-tests.c | 29 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

-- 
2.43.0

Re: [PATCH v2 0/2] mm/hmm: A fix and a selftest

Posted by Lorenzo Stoakes 5 days, 16 hours ago

On Sat, May 30, 2026 at 08:54:10AM +0000, Dev Jain wrote:
> Patch 1 fixes a stale warning present from the time when only migration
> softleaf entries were supported at the PMD level.
>
> Patch 2 adds some code into hmm-tests.c which exercises the pagemap path
> for PMD device-private entries.

Thanks!

FYI running the HMM tests locally I ran into a nasty issue that I sent a patch
for [0]!

[0]: https://lore.kernel.org/linux-mm/20260601083044.57132-1-ljs@kernel.org/

Cheers, Lorenzo

>
> ---
> Applies on mm-unstable (404fb4f38e8f).
>
> Dev Jain (2):
>   fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
>   selftests/mm/hmm-tests: test pagemap reads of PMD device-private
>     entries
>
>  fs/proc/task_mmu.c                     |  1 -
>  tools/testing/selftests/mm/hmm-tests.c | 29 ++++++++++++++++++++++++++
>  2 files changed, 29 insertions(+), 1 deletion(-)
>
> --
> 2.43.0
>

Re: [PATCH v2 0/2] mm/hmm: A fix and a selftest

Posted by Andrew Morton 6 days, 5 hours ago

On Sat, 30 May 2026 08:54:10 +0000 Dev Jain <dev.jain@arm.com> wrote:

> Patch 1 fixes a stale warning present from the time when only migration
> softleaf entries were supported at the PMD level.
> 
> Patch 2 adds some code into hmm-tests.c which exercises the pagemap path
> for PMD device-private entries.

David, I'll retain your ack on patch 1.

Sashiko has a concern about the selftest:
	https://sashiko.dev/#/patchset/20260530085413.1270139-1-dev.jain@arm.com

Re: [PATCH v2 0/2] mm/hmm: A fix and a selftest

Posted by Dev Jain 5 days, 19 hours ago


On 01/06/26 12:54 am, Andrew Morton wrote:
> On Sat, 30 May 2026 08:54:10 +0000 Dev Jain <dev.jain@arm.com> wrote:
> 
>> Patch 1 fixes a stale warning present from the time when only migration
>> softleaf entries were supported at the PMD level.
>>
>> Patch 2 adds some code into hmm-tests.c which exercises the pagemap path
>> for PMD device-private entries.
> 
> David, I'll retain your ack on patch 1.
> 
> Sashiko has a concern about the selftest:
> 	https://sashiko.dev/#/patchset/20260530085413.1270139-1-dev.jain@arm.com

Same concern as raised by Balbir.

Re: [PATCH v2 0/2] mm/hmm: A fix and a selftest

Posted by David Hildenbrand (Arm) 6 days, 5 hours ago

On 5/31/26 21:24, Andrew Morton wrote:
> On Sat, 30 May 2026 08:54:10 +0000 Dev Jain <dev.jain@arm.com> wrote:
> 
>> Patch 1 fixes a stale warning present from the time when only migration
>> softleaf entries were supported at the PMD level.
>>
>> Patch 2 adds some code into hmm-tests.c which exercises the pagemap path
>> for PMD device-private entries.
> 
> David, I'll retain your ack on patch 1.

Thanks!

-- 
Cheers,

David