kernel/linux.git/Documentation/admin-guide/mm, branch v7.2-rc1

selftests/mm: rename hugepage-* tests to hugetlb-*

2026-06-21T18:37:19+00:00

hugepage could mean both THP and HugeTLB these days. Rename hugepage-* tests for HugeTLB to hugetlb-* to avoid confusion. Make sure that Makefile update keeps alphabetical ordering of the TEST_GEN_FILES entries. Keep old binary names in .gitignore because Linus prefers it this way. Link: https://lore.kernel.org/20260511162840.375890-8-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Reviewed-by: Donet Tom Reviewed-by: Li Wang Tested-by: Sarthak Sharma Tested-by: Luiz Capitulino Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand Cc: Dev Jain Cc: Jason Gunthorpe Cc: John Hubbard Cc: Lance Yang Cc: Leon Romanovsky Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Mark Brown Cc: Michal Hocko Cc: Nico Pache Cc: Peter Xu Cc: Ryan Roberts Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

selftests/mm: merge map_hugetlb into hugepage-mmap

2026-06-21T18:37:18+00:00

Both tests create a hugettlb mapping, fill it with data and verify the data, the only difference is that one uses file-backed memory and another one uses anonymous memory. Merge both tests into a single file. Link: https://lore.kernel.org/20260511162840.375890-7-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Reviewed-by: Luiz Capitulino Reviewed-by: Donet Tom Tested-by: Luiz Capitulino Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand Cc: Dev Jain Cc: Jason Gunthorpe Cc: John Hubbard Cc: Lance Yang Cc: Leon Romanovsky Cc: Liam Howlett Cc: Li Wang Cc: Lorenzo Stoakes Cc: Mark Brown Cc: Michal Hocko Cc: Nico Pache Cc: Peter Xu Cc: Ryan Roberts Cc: Sarthak Sharma Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

Documentation: mm: update the admin guide for mTHP collapse

2026-06-21T18:31:32+00:00

Now that we can collapse to mTHPs lets update the admin guide to reflect these changes and provide proper guidance on how to utilize it. Link: https://lore.kernel.org/20260605161422.213817-15-npache@redhat.com Signed-off-by: Nico Pache Reviewed-by: Lorenzo Stoakes Reviewed-by: Bagas Sanjaya Acked-by: David Hildenbrand (Arm) Reviewed-by: Lance Yang Cc: Alistair Popple Cc: Andrea Arcangeli Cc: Anshuman Khandual Cc: Baolin Wang Cc: Barry Song Cc: Brendan Jackman Cc: Byungchul Park Cc: Catalin Marinas Cc: David Rientjes Cc: Dev Jain Cc: Gregory Price Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Jan Kara Cc: Jann Horn Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Joshua Hahn Cc: Kefeng Wang Cc: Liam R. Howlett Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Matthew Brost Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Nanyong Sun Cc: Pedro Falcato Cc: Peter Xu Cc: Rafael Aquini Cc: Rakie Kim Cc: Randy Dunlap Cc: Ryan Roberts Cc: Shivank Garg Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Takashi Iwai (SUSE) Cc: Thomas Hellström Cc: Usama Arif Cc: Usama Arif Cc: Vishal Moola (Oracle) Cc: Vlastimil Babka Cc: Wei Yang Cc: Will Deacon Cc: Yang Shi Cc: Zach O'Keefe Cc: Zi Yan Signed-off-by: Andrew Morton

mm/khugepaged: add per-order mTHP collapse failure statistics

2026-06-21T18:31:31+00:00

Add three new mTHP statistics to track collapse failures for different orders when encountering swap PTEs, excessive none PTEs, and shared PTEs: - collapse_exceed_swap_pte: Increment when mTHP collapse fails due to encountering a swap PTE. - collapse_exceed_none_pte: Counts when mTHP collapse fails due to exceeding the none PTE threshold for the given order - collapse_exceed_shared_pte: Counts when mTHP collapse fails due to encountering a shared PTE. These statistics complement the existing THP_SCAN_EXCEED_* events by providing per-order granularity for mTHP collapse attempts. The stats are exposed via sysfs under `/sys/kernel/mm/transparent_hugepage/hugepages-*/stats/` for each supported hugepage size. As we currently do not support collapsing mTHPs that contain a swap or shared entry, those statistics keep track of how often we are encountering failed mTHP collapses due to these restrictions. We will add support for mTHP collapse for anonymous pages next; lets also track when this happens at the PMD level within the per-mTHP stats. Link: https://lore.kernel.org/20260605161422.213817-9-npache@redhat.com Signed-off-by: Nico Pache Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand (Arm) Reviewed-by: Lance Yang Cc: Alistair Popple Cc: Andrea Arcangeli Cc: Anshuman Khandual Cc: Bagas Sanjaya Cc: Baolin Wang Cc: Barry Song Cc: Brendan Jackman Cc: Byungchul Park Cc: Catalin Marinas Cc: David Rientjes Cc: Dev Jain Cc: Gregory Price Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Jan Kara Cc: Jann Horn Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Joshua Hahn Cc: Kefeng Wang Cc: Liam R. Howlett Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Matthew Brost Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Nanyong Sun Cc: Pedro Falcato Cc: Peter Xu Cc: Rafael Aquini Cc: Rakie Kim Cc: Randy Dunlap Cc: Ryan Roberts Cc: Shivank Garg Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Takashi Iwai (SUSE) Cc: Thomas Hellström Cc: Usama Arif Cc: Usama Arif Cc: Vishal Moola (Oracle) Cc: Vlastimil Babka Cc: Wei Yang Cc: Will Deacon Cc: Yang Shi Cc: Zach O'Keefe Cc: Zi Yan Signed-off-by: Andrew Morton

mm/khugepaged: generalize alloc_charge_folio()

2026-06-21T18:31:29+00:00

Pass order to alloc_charge_folio() and update mTHP statistics. Link: https://lore.kernel.org/20260605161422.213817-3-npache@redhat.com Signed-off-by: Dev Jain Co-developed-by: Nico Pache Signed-off-by: Nico Pache Reviewed-by: Wei Yang Reviewed-by: Lance Yang Reviewed-by: Baolin Wang Reviewed-by: Lorenzo Stoakes Reviewed-by: Zi Yan Acked-by: Usama Arif Acked-by: David Hildenbrand (Arm) Cc: Alistair Popple Cc: Andrea Arcangeli Cc: Anshuman Khandual Cc: Bagas Sanjaya Cc: Barry Song Cc: Brendan Jackman Cc: Byungchul Park Cc: Catalin Marinas Cc: David Rientjes Cc: Gregory Price Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Jan Kara Cc: Jann Horn Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Joshua Hahn Cc: Kefeng Wang Cc: Liam R. Howlett Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Matthew Brost Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Nanyong Sun Cc: Pedro Falcato Cc: Peter Xu Cc: Rafael Aquini Cc: Rakie Kim Cc: Randy Dunlap Cc: Ryan Roberts Cc: Shivank Garg Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Takashi Iwai (SUSE) Cc: Thomas Hellström Cc: Usama Arif Cc: Vishal Moola (Oracle) Cc: Vlastimil Babka Cc: Will Deacon Cc: Yang Shi Cc: Zach O'Keefe Signed-off-by: Andrew Morton

Docs/admin-guide/mm/damon/usage: clarify current_value of quota goals

2026-06-04T21:45:02+00:00

The sysfs interface for DAMON quota goals includes a `current_value` file. This file is not updated by the kernel and only serves to receive user input. Clarify in the documentation that the kernel does not update `current_value`, and that reading it only has meaning when `target_metric` is set to `user_input`. While at it, fix missing commas in the goal files list. Link: https://lore.kernel.org/20260521202020.126500-3-maksym.shcherba@lnu.edu.ua Signed-off-by: Maksym Shcherba Reviewed-by: SeongJae Park Assisted-by: Antigravity:Gemini-3.1-Pro Signed-off-by: Andrew Morton

Docs/{ABI,admin-guide}/damon: fix various typoes

2026-06-02T22:22:34+00:00

``damon_target_idx`` was wrongly written as ``target_idx`` in the docs. Fix it all over the place, as well as the wrong directory count, grammar, etc. Link: https://lore.kernel.org/20260520012104.93602-4-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Zenghui Yu Reviewed-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport (Microsoft) Cc: niecheng Cc: Sakurai Shun Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

Documentation/admin-guide/mm: fix typos in transhuge.rst

2026-06-02T22:22:33+00:00

Fix these two typos: 1. approporiately -> appropriately 2. presure -> pressure Link: https://lore.kernel.org/20260520051751.74396-1-leon.hwang@linux.dev Signed-off-by: Leon Hwang Reviewed-by: Mike Rapoport (Microsoft) Acked-by: David Hildenbrand (Arm) Reviewed-by: Lance Yang Reviewed-by: SeongJae Park Reviewed-by: Lorenzo Stoakes Cc: Baolin Wang Cc: Barry Song Cc: Dev Jain Cc: Jonathan Corbet Cc: Leon Hwang Cc: Liam R. Howlett Cc: Michal Hocko Cc: Nico Pache Cc: Ryan Roberts Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

Docs/admin-guide/mm/damon/usage: update for memcg damon filter

2026-06-02T22:22:31+00:00

Update DAMON usage document for the newly added belonging memory cgroup attribute monitoring feature. Link: https://lore.kernel.org/20260518234119.97569-29-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Shuah Khan Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

Docs/admin-guide/mm/damon/usage: document data attributes monitoring

2026-06-02T22:22:29+00:00

Update DAMON usage document for the newly added data attributes monitoring feature. Link: https://lore.kernel.org/20260518234119.97569-22-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Shuah Khan Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton