forked from mirrors/linux
		
	
	
		
			356 commits
		
	
	
	| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
|  Fan Ni | 7f4b6065d9 | mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page The function __unmap_hugepage_range() has two kinds of users: 1) unmap_hugepage_range(), which passes in the head page of a folio. Since unmap_hugepage_range() already takes folio and there are no other uses of the folio struct in the function, it is natural for __unmap_hugepage_range() to take folio also. 2) All other uses, which pass in NULL pointer. In both cases, we can pass in folio. Refactor __unmap_hugepage_range() to take folio. Link: https://lkml.kernel.org/r/20250505182345.506888-5-nifan.cxl@gmail.com Signed-off-by: Fan Ni <fan.ni@samsung.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Fan Ni | 81edb1ba32 | mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page The function unmap_hugepage_range() has two kinds of users: 1) unmap_ref_private(), which passes in the head page of a folio. Since unmap_ref_private() already takes folio and there are no other uses of the folio struct in the function, it is natural for unmap_hugepage_range() to take folio also. 2) All other uses, which pass in NULL pointer. In both cases, we can pass in folio. Refactor unmap_hugepage_range() to take folio. Link: https://lkml.kernel.org/r/20250505182345.506888-4-nifan.cxl@gmail.com Signed-off-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | 8d88b0769e | mm/hugetlb: use separate nodemask for bootmem allocations Hugetlb boot allocation has used online nodes for allocation since commit | ||
|  Vishal Moola (Oracle) | b4c829fa4d | mm/compaction: use folio in hugetlb pathway Use a folio in the hugetlb pathway during the compaction migrate-able pageblock scan. This removes a call to compound_head(). Link: https://lkml.kernel.org/r/20250401021025.637333-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | d2d7867140 | mm/hugetlb: enable bootmem allocation from CMA areas If hugetlb_cma_only is enabled, we know that hugetlb pages can only be allocated from CMA. Now that there is an interface to do early reservations from a CMA area (returning memblock memory), it can be used to allocate hugetlb pages from CMA. This also allows for doing pre-HVO on these pages (if enabled). Make sure to initialize the page structures and associated data correctly. Create a flag to signal that a hugetlb page has been allocated from CMA to make things a little easier. Some configurations of powerpc have a special hugetlb bootmem allocator, so introduce a boolean arch_specific_huge_bootmem_alloc that returns true if such an allocator is present. In that case, CMA bootmem allocations can't be used, so check that function before trying. Link: https://lkml.kernel.org/r/20250228182928.2645936-27-fvdl@google.com Signed-off-by: Frank van der Linden <fvdl@google.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | b1222550fb | mm/hugetlb: do pre-HVO for bootmem allocated pages For large systems, the overhead of vmemmap pages for hugetlb is
substantial.  It's about 1.5% of memory, which is about 45G for a 3T
system.  If you want to configure most of that system for hugetlb (e.g. 
to use as backing memory for VMs), there is a chance of running out of
memory on boot, even though you know that the 45G will become available
later.
To avoid this scenario, and since it's a waste to first allocate and then
free that 45G during boot, do pre-HVO for hugetlb bootmem allocated pages
('gigantic' pages).
pre-HVO is done by adding functions that are called from
sparse_init_nid_early and sparse_init_nid_late.  The first is called
before memmap allocation, so it takes care of allocating memmap HVO-style.
The second verifies that all bootmem pages look good, specifically it
checks that they do not intersect with multiple zones.  This can only be
done from sparse_init_nid_late path, when zones have been initialized.
The hugetlb page size must be aligned to the section size, and aligned to
the size of memory described by the number of page structures contained in
one PMD (since pre-HVO is not prepared to split PMDs).  This should be
true for most 'gigantic' pages, it is for 1G pages on x86, where both of
these alignment requirements are 128M.
This will only have an effect if hugetlb_bootmem_alloc was called early in
boot.  If not, it won't do anything, and HVO for bootmem hugetlb pages
works as before.
Link: https://lkml.kernel.org/r/20250228182928.2645936-20-fvdl@google.com
Signed-off-by: Frank van der Linden <fvdl@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | 752fe17af6 | mm/hugetlb: add pre-HVO framework Define flags for pre-HVOed bootmem hugetlb pages, and act on them. The most important flag is the HVO flag, signalling that a bootmem allocated gigantic page has already been HVO-ed. If this flag is seen by the hugetlb bootmem gather code, the page is marked as HVO optimized. The HVO code will then not try to optimize it again. Instead, it will just map the tail page mirror pages read-only, completing the HVO steps. No functional change, as nothing sets the flags yet. Link: https://lkml.kernel.org/r/20250228182928.2645936-18-fvdl@google.com Signed-off-by: Frank van der Linden <fvdl@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | d58b249820 | mm/hugetlb: deal with multiple calls to hugetlb_bootmem_alloc Architectures that want pre-HVO of hugetlb vmemmap pages will need to call hugetlb_bootmem_alloc from an earlier spot in boot (before sparse_init). To facilitate some architectures doing this, protect hugetlb_bootmem_alloc against multiple calls. Also provide a helper function to check if it's been called, so that the early HVO code, to be added later, can see if there is anything to do. Link: https://lkml.kernel.org/r/20250228182928.2645936-16-fvdl@google.com Signed-off-by: Frank van der Linden <fvdl@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Frank van der Linden | 5b47c02967 | mm/hugetlb: convert cmdline parameters from setup to early Convert the cmdline parameters (hugepagesz, hugepages, default_hugepagesz and hugetlb_free_vmemmap) to early parameters. Since parse_early_param might run before MMU setups on some platforms (powerpc), validation of huge page sizes as specified in command line parameters would fail. So instead, for the hstate-related values, just record the them and parse them on demand, from hugetlb_bootmem_alloc. The allocation of hugetlb bootmem pages is now done in hugetlb_bootmem_alloc, which is called explicitly at the start of mm_core_init(). core_initcall would be too late, as that happens with memblock already torn down. This change will allow earlier allocation and initialization of bootmem hugetlb pages later on. No functional change intended. Link: https://lkml.kernel.org/r/20250228182928.2645936-8-fvdl@google.com Signed-off-by: Frank van der Linden <fvdl@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Linus Torvalds | 1110ce6a1e | 33 hotfixes.  24 are cc:stable and the remainder address post-6.13 issues or aren't considered necessary for -stable kernels.
 
 26 are for MM and 7 are for non-MM.
 
 - "mm: memory_failure: unmap poisoned folio during migrate properly"
   from Ma Wupeng fixes a couple of two year old bugs involving the
   migration of hwpoisoned folios.
 
 - "selftests/damon: three fixes for false results" from SeongJae Park
   fixes three one year old bugs in the SAMON selftest code.
 
 The remainder are singletons and doubletons.  Please see the individual
 changelogs for details.
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Merge tag 'mm-hotfixes-stable-2025-03-08-16-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
 "33 hotfixes. 24 are cc:stable and the remainder address post-6.13
  issues or aren't considered necessary for -stable kernels.
  26 are for MM and 7 are for non-MM.
   - "mm: memory_failure: unmap poisoned folio during migrate properly"
     from Ma Wupeng fixes a couple of two year old bugs involving the
     migration of hwpoisoned folios.
   - "selftests/damon: three fixes for false results" from SeongJae Park
     fixes three one year old bugs in the SAMON selftest code.
  The remainder are singletons and doubletons. Please see the individual
  changelogs for details"
* tag 'mm-hotfixes-stable-2025-03-08-16-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (33 commits)
  mm/page_alloc: fix uninitialized variable
  rapidio: add check for rio_add_net() in rio_scan_alloc_net()
  rapidio: fix an API misues when rio_add_net() fails
  MAINTAINERS: .mailmap: update Sumit Garg's email address
  Revert "mm/page_alloc.c: don't show protection in zone's ->lowmem_reserve[] for empty zone"
  mm: fix finish_fault() handling for large folios
  mm: don't skip arch_sync_kernel_mappings() in error paths
  mm: shmem: remove unnecessary warning in shmem_writepage()
  userfaultfd: fix PTE unmapping stack-allocated PTE copies
  userfaultfd: do not block on locking a large folio with raised refcount
  mm: zswap: use ATOMIC_LONG_INIT to initialize zswap_stored_pages
  mm: shmem: fix potential data corruption during shmem swapin
  mm: fix kernel BUG when userfaultfd_move encounters swapcache
  selftests/damon/damon_nr_regions: sort collected regiosn before checking with min/max boundaries
  selftests/damon/damon_nr_regions: set ops update for merge results check to 100ms
  selftests/damon/damos_quota: make real expectation of quota exceeds
  include/linux/log2.h: mark is_power_of_2() with __always_inline
  NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
  mm, swap: avoid BUG_ON in relocate_cluster()
  mm: swap: use correct step in loop to wait all clusters in wait_for_allocation()
  ... | ||
|  Ge Yang | 67bab13307 | mm/hugetlb: wait for hugetlb folios to be freed Since the introduction of commit | ||
|  Ryan Roberts | 02410ac72a | mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear() In order to fix a bug, arm64 needs to be told the size of the huge page
for which the huge_pte is being cleared in huge_ptep_get_and_clear().
Provide for this by adding an `unsigned long sz` parameter to the
function. This follows the same pattern as huge_pte_clear() and
set_huge_pte_at().
This commit makes the required interface modifications to the core mm as
well as all arches that implement this function (arm64, loongarch, mips,
parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed
in a separate commit.
Cc: stable@vger.kernel.org
Fixes:  | ||
|  David Hildenbrand | b235448e8c | mm/hugetlb: rename folio_putback_active_hugetlb() to folio_putback_hugetlb() Now that folio_putback_hugetlb() is only called on folios that were previously isolated through folio_isolate_hugetlb(), let's rename it to match folio_putback_lru(). Add some kernel doc to clarify how this function is supposed to be used. Link: https://lkml.kernel.org/r/20250113131611.2554758-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  David Hildenbrand | 4c640f1280 | mm/hugetlb: rename isolate_hugetlb() to folio_isolate_hugetlb() Let's make the function name match "folio_isolate_lru()", and add some kernel doc. Link: https://lkml.kernel.org/r/20250113131611.2554758-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Peter Xu | 30cef82bc6 | mm/hugetlb: rename avoid_reserve to cow_from_owner The old name "avoid_reserve" can be too generic and can be used wrongly in the new call sites that want to allocate a hugetlb folio. It's confusing on two things: (1) whether one can opt-in to avoid global reservation, and (2) whether it should take more than one count. In reality, this flag is only used in an extremely hacky path, in an extremely hacky way in hugetlb CoW path only, and always use with 1 saying "skip global reservation". Rename the flag to avoid future abuse of this flag, making it a boolean so as to reflect its true representation that it's not a counter. To make it even harder to abuse, add a comment above the function to explain it. Link: https://lkml.kernel.org/r/20250107204002.2683356-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Ackerley Tng <ackerleytng@google.com> Cc: Breno Leitao <leitao@debian.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  yangge | 04f13d241b | mm: replace free hugepage folios after migration My machine has 4 NUMA nodes, each equipped with 32GB of memory.  I have
configured each NUMA node with 16GB of CMA and 16GB of in-use hugetlb
pages.  The allocation of contiguous memory via cma_alloc() can fail
probabilistically.
When there are free hugetlb folios in the hugetlb pool, during the
migration of in-use hugetlb folios, new folios are allocated from the free
hugetlb pool.  After the migration is completed, the old folios are
released back to the free hugetlb pool instead of being returned to the
buddy system.  This can cause test_pages_isolated() check to fail,
ultimately leading to the failure of cma_alloc().
Call trace:
cma_alloc()
    __alloc_contig_migrate_range() // migrate in-use hugepage
    test_pages_isolated()
        __test_page_isolated_in_pageblock()
             PageBuddy(page) // check if the page is in buddy
To address this issue, we introduce a function named
replace_free_hugepage_folios().  This function will replace the hugepage
in the free hugepage pool with a new one and release the old one to the
buddy system.  After the migration of in-use hugetlb pages is completed,
we will invoke replace_free_hugepage_folios() to ensure that these
hugepages are properly released to the buddy system.  Following this step,
when test_pages_isolated() is executed for inspection, it will
successfully pass.
Additionally, when alloc_contig_range() is used to migrate multiple in-use
hugetlb pages, it can result in some in-use hugetlb pages being released
back to the free hugetlb pool and subsequently being reallocated and used
again.  For example:
[huge 0] [huge 1]
To migrate huge 0, we obtain huge x from the pool.  After the migration is
completed, we return the now-freed huge 0 back to the pool.  When it's
time to migrate huge 1, we can simply reuse the now-freed huge 0 from the
pool.  As a result, when replace_free_hugepage_folios() is executed, it
cannot release huge 0 back to the buddy system.  To address this issue, we
should prevent the reuse of isolated free hugepages during the migration
process.
Link: https://lkml.kernel.org/r/1734503588-16254-1-git-send-email-yangge1116@126.com
Link: https://lkml.kernel.org/r/1736582300-11364-1-git-send-email-yangge1116@126.com
Signed-off-by: yangge <yangge1116@126.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Oscar Salvador | cc92882ee2 | mm: drop hugetlb_get_unmapped_area{_*} functions Hugetlb mappings are now handled through normal channels just like any other mapping, so we no longer need hugetlb_get_unmapped_area* specific functions. Link: https://lkml.kernel.org/r/20241007075037.267650-8-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Oscar Salvador | 7bd3f1e1a9 | mm: make hugetlb mappings go through mm_get_unmapped_area_vmflags Hugetlb mappings will no longer be special cased but rather go through the generic mm_get_unmapped_area_vmflags function. For that to happen, let us remove the .get_unmapped_area from hugetlbfs_file_operations struct, and hint __get_unmapped_area that it should not send hugetlb mappings through thp_get_unmapped_area_vmflags but through mm_get_unmapped_area_vmflags. Create also a function called hugetlb_mmap_check_and_align() where a couple of safety checks are being done and the addr is aligned to the huge page size. Otherwise we will have to do this in every single function, which duplicates quite a lot of code. Link: https://lkml.kernel.org/r/20241007075037.267650-7-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Oscar Salvador | 7f24cbc9c4 | mm/mmap: teach generic_get_unmapped_area{_topdown} to handle hugetlb mappings Patch series "Unify hugetlb into arch_get_unmapped_area functions", v4.
This is an attempt to get rid of a fair amount of duplicated code wrt. 
hugetlb and *get_unmapped_area* functions.
HugeTLB registers a .get_unmapped_area function which gets called from
__get_unmapped_area().
hugetlb_get_unmapped_area() is defined by a bunch of architectures and
it also has a generic definition for those that do not define it.
Short-long story is that there is a ton of duplicated code between
specific hugetlb *_get_unmapped_area_* functions and mm-core functions,
so we can do better by teaching arch_get_unmapped_area* functions how
to deal with hugetlb mappings.
Note that not a lot of things need to be taught though. 
hugetlb_get_unmapped_area, that gets called for hugetlb mappings, runs
some sanity checks prior to calling mm_get_unmapped_area_vmflags(), so we
do not need to that down the road in the respective
{generic,arch}_get_unmapped_area* functions.
More information can be found in the respective patches.
LTP mmapstress hugetlb selftests were ran succesfully on:
This patch (of 9):
We want to stop special casing hugetlb mappings and make them go through
generic channels, so teach generic_get_unmapped_area{_topdown} to handle
those.  The main difference is that we set info.align_mask for huge
mappings.
Link: https://lkml.kernel.org/r/20241007075037.267650-1-osalvador@suse.de
Link: https://lkml.kernel.org/r/20241007075037.267650-2-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Steve Sistare | 26a8ea8092 | mm/hugetlb: fix memfd_pin_folios resv_huge_pages leak memfd_pin_folios followed by unpin_folios leaves resv_huge_pages elevated
if the pages were not already faulted in.  During a normal page fault,
resv_huge_pages is consumed here:
hugetlb_fault()
  alloc_hugetlb_folio()
    dequeue_hugetlb_folio_vma()
      dequeue_hugetlb_folio_nodemask()
        dequeue_hugetlb_folio_node_exact()
          free_huge_pages--
      resv_huge_pages--
During memfd_pin_folios, the page is created by calling
alloc_hugetlb_folio_nodemask instead of alloc_hugetlb_folio, and
resv_huge_pages is not modified:
memfd_alloc_folio()
  alloc_hugetlb_folio_nodemask()
    dequeue_hugetlb_folio_nodemask()
      dequeue_hugetlb_folio_node_exact()
        free_huge_pages--
alloc_hugetlb_folio_nodemask has other callers that must not modify
resv_huge_pages.  Therefore, to fix, define an alternate version of
alloc_hugetlb_folio_nodemask for this call site that adjusts
resv_huge_pages.
Link: https://lkml.kernel.org/r/1725373521-451395-4-git-send-email-steven.sistare@oracle.com
Fixes:  | ||
|  Yu Zhao | cf54f310d0 | mm/hugetlb: use __GFP_COMP for gigantic folios Use __GFP_COMP for gigantic folios to greatly reduce not only the amount
of code but also the allocation and free time.
LOC (approximately): +60, -240
Allocate and free 500 1GB hugeTLB memory without HVO by:
  time echo 500 >/sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
  time echo 0 >/sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
       Before  After
Alloc  ~13s    ~10s
Free   ~15s    <1s
The above magnitude generally holds for multiple x86 and arm64 CPU models.
Link: https://lkml.kernel.org/r/20240814035451.773331-4-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: Frank van der Linden <fvdl@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  David Hildenbrand | 94ccd21e9a | mm/hugetlb: remove hugetlb_follow_page_mask() leftover We removed hugetlb_follow_page_mask() in commit  | ||
|  David Hildenbrand | 188cac58a8 | mm/hugetlb: enforce that PMD PT sharing has split PMD PT locks Sharing page tables between processes but falling back to per-MM page table locks cannot possibly work. So, let's make sure that we do have split PMD locks by adding a new Kconfig option and letting that depend on CONFIG_SPLIT_PMD_PTLOCKS. Link: https://lkml.kernel.org/r/20240726150728.3159964-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  David Hildenbrand | 5f75cfbd6b | mm/hugetlb: fix hugetlb vs. core-mm PT locking We recently made GUP's common page table walking code to also walk hugetlb
VMAs without most hugetlb special-casing, preparing for the future of
having less hugetlb-specific page table walking code in the codebase. 
Turns out that we missed one page table locking detail: page table locking
for hugetlb folios that are not mapped using a single PMD/PUD.
Assume we have hugetlb folio that spans multiple PTEs (e.g., 64 KiB
hugetlb folios on arm64 with 4 KiB base page size).  GUP, as it walks the
page tables, will perform a pte_offset_map_lock() to grab the PTE table
lock.
However, hugetlb that concurrently modifies these page tables would
actually grab the mm->page_table_lock: with USE_SPLIT_PTE_PTLOCKS, the
locks would differ.  Something similar can happen right now with hugetlb
folios that span multiple PMDs when USE_SPLIT_PMD_PTLOCKS.
This issue can be reproduced [1], for example triggering:
[ 3105.936100] ------------[ cut here ]------------
[ 3105.939323] WARNING: CPU: 31 PID: 2732 at mm/gup.c:142 try_grab_folio+0x11c/0x188
[ 3105.944634] Modules linked in: [...]
[ 3105.974841] CPU: 31 PID: 2732 Comm: reproducer Not tainted 6.10.0-64.eln141.aarch64 #1
[ 3105.980406] Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-4.fc40 05/24/2024
[ 3105.986185] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 3105.991108] pc : try_grab_folio+0x11c/0x188
[ 3105.994013] lr : follow_page_pte+0xd8/0x430
[ 3105.996986] sp : ffff80008eafb8f0
[ 3105.999346] x29: ffff80008eafb900 x28: ffffffe8d481f380 x27: 00f80001207cff43
[ 3106.004414] x26: 0000000000000001 x25: 0000000000000000 x24: ffff80008eafba48
[ 3106.009520] x23: 0000ffff9372f000 x22: ffff7a54459e2000 x21: ffff7a546c1aa978
[ 3106.014529] x20: ffffffe8d481f3c0 x19: 0000000000610041 x18: 0000000000000001
[ 3106.019506] x17: 0000000000000001 x16: ffffffffffffffff x15: 0000000000000000
[ 3106.024494] x14: ffffb85477fdfe08 x13: 0000ffff9372ffff x12: 0000000000000000
[ 3106.029469] x11: 1fffef4a88a96be1 x10: ffff7a54454b5f0c x9 : ffffb854771b12f0
[ 3106.034324] x8 : 0008000000000000 x7 : ffff7a546c1aa980 x6 : 0008000000000080
[ 3106.038902] x5 : 00000000001207cf x4 : 0000ffff9372f000 x3 : ffffffe8d481f000
[ 3106.043420] x2 : 0000000000610041 x1 : 0000000000000001 x0 : 0000000000000000
[ 3106.047957] Call trace:
[ 3106.049522]  try_grab_folio+0x11c/0x188
[ 3106.051996]  follow_pmd_mask.constprop.0.isra.0+0x150/0x2e0
[ 3106.055527]  follow_page_mask+0x1a0/0x2b8
[ 3106.058118]  __get_user_pages+0xf0/0x348
[ 3106.060647]  faultin_page_range+0xb0/0x360
[ 3106.063651]  do_madvise+0x340/0x598
Let's make huge_pte_lockptr() effectively use the same PT locks as any
core-mm page table walker would.  Add ptep_lockptr() to obtain the PTE
page table lock using a pte pointer -- unfortunately we cannot convert
pte_lockptr() because virt_to_page() doesn't work with kmap'ed page tables
we can have with CONFIG_HIGHPTE.
Handle CONFIG_PGTABLE_LEVELS correctly by checking in reverse order, such
that when e.g., CONFIG_PGTABLE_LEVELS==2 with
PGDIR_SIZE==P4D_SIZE==PUD_SIZE==PMD_SIZE will work as expected.  Document
why that works.
There is one ugly case: powerpc 8xx, whereby we have an 8 MiB hugetlb
folio being mapped using two PTE page tables.  While hugetlb wants to take
the PMD table lock, core-mm would grab the PTE table lock of one of both
PTE page tables.  In such corner cases, we have to make sure that both
locks match, which is (fortunately!) currently guaranteed for 8xx as it
does not support SMP and consequently doesn't use split PT locks.
[1] https://lore.kernel.org/all/1bbfcc7f-f222-45a5-ac44-c5a1381c596d@redhat.com/
Link: https://lkml.kernel.org/r/20240801204748.99107-1-david@redhat.com
Fixes:  | ||
|  Miaohe Lin | 667574e873 | mm/hugetlb: fix possible recursive locking detected warning When tries to demote 1G hugetlb folios, a lockdep warning is observed:
============================================
WARNING: possible recursive locking detected
6.10.0-rc6-00452-ga4d0275fa660-dirty #79 Not tainted
--------------------------------------------
bash/710 is trying to acquire lock:
ffffffff8f0a7850 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0x244/0x460
but task is already holding lock:
ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460
other info that might help us debug this:
 Possible unsafe locking scenario:
       CPU0
       ----
  lock(&h->resize_lock);
  lock(&h->resize_lock);
 *** DEADLOCK ***
 May be due to missing lock nesting notation
4 locks held by bash/710:
 #0: ffff8f118439c3f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
 #1: ffff8f11893b9e88 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0
 #2: ffff8f1183dc4428 (kn->active#98){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0
 #3: ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460
stack backtrace:
CPU: 3 PID: 710 Comm: bash Not tainted 6.10.0-rc6-00452-ga4d0275fa660-dirty #79
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xa0
 __lock_acquire+0x10f2/0x1ca0
 lock_acquire+0xbe/0x2d0
 __mutex_lock+0x6d/0x400
 demote_store+0x244/0x460
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xb9/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa61db14887
RSP: 002b:00007ffc56c48358 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa61db14887
RDX: 0000000000000002 RSI: 000055a030050220 RDI: 0000000000000001
RBP: 000055a030050220 R08: 00007fa61dbd1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007fa61dc1b780 R14: 00007fa61dc17600 R15: 00007fa61dc16a00
 </TASK>
Lockdep considers this an AA deadlock because the different resize_lock
mutexes reside in the same lockdep class, but this is a false positive.
Place them in distinct classes to avoid these warnings.
Link: https://lkml.kernel.org/r/20240712031314.2570452-1-linmiaohe@huawei.com
Fixes:  | ||
|  Christophe Leroy | 8268614b40 | mm: remove CONFIG_ARCH_HAS_HUGEPD powerpc was the only user of CONFIG_ARCH_HAS_HUGEPD and doesn't use it anymore, so remove all related code. Link: https://lkml.kernel.org/r/4b10c54c794780b955f3ad6c657d0199dd792146.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Xiu Jianfeng | b79d715c43 | mm/hugetlb_cgroup: switch to the new cftypes The previous patch has already reconstructed the cftype attributes based on the templates and saved them in dfl_cftypes and legacy_cftypes. then remove the old procedure and switch to the new cftypes. Link: https://lkml.kernel.org/r/20240612092409.2027592-4-xiujianfeng@huawei.com Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Sidhartha Kumar | 16540dae95 | mm/hugetlb: mm/memory_hotplug: use a folio in scan_movable_pages() By using a folio in scan_movable_pages() we convert the last user of the page-based hugetlb information macro functions to the folio version. After this conversion, we can safely remove the page-based definitions from include/linux/hugetlb.h. Link: https://lkml.kernel.org/r/20240530171427.242018-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Sidhartha Kumar | 63818aaf0d | mm/hugetlb: remove {Set,Clear}Hpage macros All users have been converted to use the folio version of these macros, we can safely remove the page based interface. Link: https://lkml.kernel.org/r/20240520224407.110062-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Linus Torvalds | 61307b7be4 | The usual shower of singleton fixes and minor series all over MM, documented (hopefully adequately) in the respective changelogs.  Notable
 series include:
 
 - Lucas Stach has provided some page-mapping
   cleanup/consolidation/maintainability work in the series "mm/treewide:
   Remove pXd_huge() API".
 
 - In the series "Allow migrate on protnone reference with
   MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
   MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one
   test.
 
 - In their series "Memory allocation profiling" Kent Overstreet and
   Suren Baghdasaryan have contributed a means of determining (via
   /proc/allocinfo) whereabouts in the kernel memory is being allocated:
   number of calls and amount of memory.
 
 - Matthew Wilcox has provided the series "Various significant MM
   patches" which does a number of rather unrelated things, but in largely
   similar code sites.
 
 - In his series "mm: page_alloc: freelist migratetype hygiene" Johannes
   Weiner has fixed the page allocator's handling of migratetype requests,
   with resulting improvements in compaction efficiency.
 
 - In the series "make the hugetlb migration strategy consistent" Baolin
   Wang has fixed a hugetlb migration issue, which should improve hugetlb
   allocation reliability.
 
 - Liu Shixin has hit an I/O meltdown caused by readahead in a
   memory-tight memcg.  Addressed in the series "Fix I/O high when memory
   almost met memcg limit".
 
 - In the series "mm/filemap: optimize folio adding and splitting" Kairui
   Song has optimized pagecache insertion, yielding ~10% performance
   improvement in one test.
 
 - Baoquan He has cleaned up and consolidated the early zone
   initialization code in the series "mm/mm_init.c: refactor
   free_area_init_core()".
 
 - Baoquan has also redone some MM initializatio code in the series
   "mm/init: minor clean up and improvement".
 
 - MM helper cleanups from Christoph Hellwig in his series "remove
   follow_pfn".
 
 - More cleanups from Matthew Wilcox in the series "Various page->flags
   cleanups".
 
 - Vlastimil Babka has contributed maintainability improvements in the
   series "memcg_kmem hooks refactoring".
 
 - More folio conversions and cleanups in Matthew Wilcox's series
 
 	"Convert huge_zero_page to huge_zero_folio"
 	"khugepaged folio conversions"
 	"Remove page_idle and page_young wrappers"
 	"Use folio APIs in procfs"
 	"Clean up __folio_put()"
 	"Some cleanups for memory-failure"
 	"Remove page_mapping()"
 	"More folio compat code removal"
 
 - David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb
   functions to work on folis".
 
 - Code consolidation and cleanup work related to GUP's handling of
   hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
 
 - Rick Edgecombe has developed some fixes to stack guard gaps in the
   series "Cover a guard gap corner case".
 
 - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series
   "mm/ksm: fix ksm exec support for prctl".
 
 - Baolin Wang has implemented NUMA balancing for multi-size THPs.  This
   is a simple first-cut implementation for now.  The series is "support
   multi-size THP numa balancing".
 
 - Cleanups to vma handling helper functions from Matthew Wilcox in the
   series "Unify vma_address and vma_pgoff_address".
 
 - Some selftests maintenance work from Dev Jain in the series
   "selftests/mm: mremap_test: Optimizations and style fixes".
 
 - Improvements to the swapping of multi-size THPs from Ryan Roberts in
   the series "Swap-out mTHP without splitting".
 
 - Kefeng Wang has significantly optimized the handling of arm64's
   permission page faults in the series
 
 	"arch/mm/fault: accelerate pagefault when badaccess"
 	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
 
 - GUP cleanups from David Hildenbrand in "mm/gup: consistently call it
   GUP-fast".
 
 - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to
   use struct vm_fault".
 
 - selftests build fixes from John Hubbard in the series "Fix
   selftests/mm build without requiring "make headers"".
 
 - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
   series "Improved Memory Tier Creation for CPUless NUMA Nodes".  Fixes
   the initialization code so that migration between different memory types
   works as intended.
 
 - David Hildenbrand has improved follow_pte() and fixed an errant driver
   in the series "mm: follow_pte() improvements and acrn follow_pte()
   fixes".
 
 - David also did some cleanup work on large folio mapcounts in his
   series "mm: mapcount for large folios + page_mapcount() cleanups".
 
 - Folio conversions in KSM in Alex Shi's series "transfer page to folio
   in KSM".
 
 - Barry Song has added some sysfs stats for monitoring multi-size THP's
   in the series "mm: add per-order mTHP alloc and swpout counters".
 
 - Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled
   and limit checking cleanups".
 
 - Matthew Wilcox has been looking at buffer_head code and found the
   documentation to be lacking.  The series is "Improve buffer head
   documentation".
 
 - Multi-size THPs get more work, this time from Lance Yang.  His series
   "mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes
   the freeing of these things.
 
 - Kemeng Shi has added more userspace-visible writeback instrumentation
   in the series "Improve visibility of writeback".
 
 - Kemeng Shi then sent some maintenance work on top in the series "Fix
   and cleanups to page-writeback".
 
 - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the
   series "Improve anon_vma scalability for anon VMAs".  Intel's test bot
   reported an improbable 3x improvement in one test.
 
 - SeongJae Park adds some DAMON feature work in the series
 
 	"mm/damon: add a DAMOS filter type for page granularity access recheck"
 	"selftests/damon: add DAMOS quota goal test"
 
 - Also some maintenance work in the series
 
 	"mm/damon/paddr: simplify page level access re-check for pageout"
 	"mm/damon: misc fixes and improvements"
 
 - David Hildenbrand has disabled some known-to-fail selftests ni the
   series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL".
 
 - memcg metadata storage optimizations from Shakeel Butt in "memcg:
   reduce memory consumption by memcg stats".
 
 - DAX fixes and maintenance work from Vishal Verma in the series
   "dax/bus.c: Fixups for dax-bus locking".
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Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
 "The usual shower of singleton fixes and minor series all over MM,
  documented (hopefully adequately) in the respective changelogs.
  Notable series include:
   - Lucas Stach has provided some page-mapping cleanup/consolidation/
     maintainability work in the series "mm/treewide: Remove pXd_huge()
     API".
   - In the series "Allow migrate on protnone reference with
     MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
     MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
     one test.
   - In their series "Memory allocation profiling" Kent Overstreet and
     Suren Baghdasaryan have contributed a means of determining (via
     /proc/allocinfo) whereabouts in the kernel memory is being
     allocated: number of calls and amount of memory.
   - Matthew Wilcox has provided the series "Various significant MM
     patches" which does a number of rather unrelated things, but in
     largely similar code sites.
   - In his series "mm: page_alloc: freelist migratetype hygiene"
     Johannes Weiner has fixed the page allocator's handling of
     migratetype requests, with resulting improvements in compaction
     efficiency.
   - In the series "make the hugetlb migration strategy consistent"
     Baolin Wang has fixed a hugetlb migration issue, which should
     improve hugetlb allocation reliability.
   - Liu Shixin has hit an I/O meltdown caused by readahead in a
     memory-tight memcg. Addressed in the series "Fix I/O high when
     memory almost met memcg limit".
   - In the series "mm/filemap: optimize folio adding and splitting"
     Kairui Song has optimized pagecache insertion, yielding ~10%
     performance improvement in one test.
   - Baoquan He has cleaned up and consolidated the early zone
     initialization code in the series "mm/mm_init.c: refactor
     free_area_init_core()".
   - Baoquan has also redone some MM initializatio code in the series
     "mm/init: minor clean up and improvement".
   - MM helper cleanups from Christoph Hellwig in his series "remove
     follow_pfn".
   - More cleanups from Matthew Wilcox in the series "Various
     page->flags cleanups".
   - Vlastimil Babka has contributed maintainability improvements in the
     series "memcg_kmem hooks refactoring".
   - More folio conversions and cleanups in Matthew Wilcox's series:
	"Convert huge_zero_page to huge_zero_folio"
	"khugepaged folio conversions"
	"Remove page_idle and page_young wrappers"
	"Use folio APIs in procfs"
	"Clean up __folio_put()"
	"Some cleanups for memory-failure"
	"Remove page_mapping()"
	"More folio compat code removal"
   - David Hildenbrand chipped in with "fs/proc/task_mmu: convert
     hugetlb functions to work on folis".
   - Code consolidation and cleanup work related to GUP's handling of
     hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
   - Rick Edgecombe has developed some fixes to stack guard gaps in the
     series "Cover a guard gap corner case".
   - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
     series "mm/ksm: fix ksm exec support for prctl".
   - Baolin Wang has implemented NUMA balancing for multi-size THPs.
     This is a simple first-cut implementation for now. The series is
     "support multi-size THP numa balancing".
   - Cleanups to vma handling helper functions from Matthew Wilcox in
     the series "Unify vma_address and vma_pgoff_address".
   - Some selftests maintenance work from Dev Jain in the series
     "selftests/mm: mremap_test: Optimizations and style fixes".
   - Improvements to the swapping of multi-size THPs from Ryan Roberts
     in the series "Swap-out mTHP without splitting".
   - Kefeng Wang has significantly optimized the handling of arm64's
     permission page faults in the series
	"arch/mm/fault: accelerate pagefault when badaccess"
	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
   - GUP cleanups from David Hildenbrand in "mm/gup: consistently call
     it GUP-fast".
   - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
     path to use struct vm_fault".
   - selftests build fixes from John Hubbard in the series "Fix
     selftests/mm build without requiring "make headers"".
   - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
     series "Improved Memory Tier Creation for CPUless NUMA Nodes".
     Fixes the initialization code so that migration between different
     memory types works as intended.
   - David Hildenbrand has improved follow_pte() and fixed an errant
     driver in the series "mm: follow_pte() improvements and acrn
     follow_pte() fixes".
   - David also did some cleanup work on large folio mapcounts in his
     series "mm: mapcount for large folios + page_mapcount() cleanups".
   - Folio conversions in KSM in Alex Shi's series "transfer page to
     folio in KSM".
   - Barry Song has added some sysfs stats for monitoring multi-size
     THP's in the series "mm: add per-order mTHP alloc and swpout
     counters".
   - Some zswap cleanups from Yosry Ahmed in the series "zswap
     same-filled and limit checking cleanups".
   - Matthew Wilcox has been looking at buffer_head code and found the
     documentation to be lacking. The series is "Improve buffer head
     documentation".
   - Multi-size THPs get more work, this time from Lance Yang. His
     series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
     optimizes the freeing of these things.
   - Kemeng Shi has added more userspace-visible writeback
     instrumentation in the series "Improve visibility of writeback".
   - Kemeng Shi then sent some maintenance work on top in the series
     "Fix and cleanups to page-writeback".
   - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
     the series "Improve anon_vma scalability for anon VMAs". Intel's
     test bot reported an improbable 3x improvement in one test.
   - SeongJae Park adds some DAMON feature work in the series
	"mm/damon: add a DAMOS filter type for page granularity access recheck"
	"selftests/damon: add DAMOS quota goal test"
   - Also some maintenance work in the series
	"mm/damon/paddr: simplify page level access re-check for pageout"
	"mm/damon: misc fixes and improvements"
   - David Hildenbrand has disabled some known-to-fail selftests ni the
     series "selftests: mm: cow: flag vmsplice() hugetlb tests as
     XFAIL".
   - memcg metadata storage optimizations from Shakeel Butt in "memcg:
     reduce memory consumption by memcg stats".
   - DAX fixes and maintenance work from Vishal Verma in the series
     "dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
  memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
  selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
  selftests: cgroup: add tests to verify the zswap writeback path
  mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
  mm/damon/core: fix return value from damos_wmark_metric_value
  mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
  selftests: cgroup: remove redundant enabling of memory controller
  Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
  Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
  Docs/mm/damon/design: use a list for supported filters
  Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
  Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
  selftests/damon: classify tests for functionalities and regressions
  selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
  selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
  selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
  mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
  selftests/damon: add a test for DAMOS quota goal
  ... | ||
|  Matthew Wilcox (Oracle) | 6e8cda4c2c | mm: convert hugetlb_page_mapping_lock_write to folio The page is only used to get the mapping, so the folio will do just as well. Both callers already have a folio available, so this saves a call to compound_head(). Link: https://lkml.kernel.org/r/20240412193510.2356957-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Sidhartha Kumar | d199483c2b | mm/hugetlb: rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folios() dissolve_free_huge_pages() only uses folios internally, rename it to dissolve_free_hugetlb_folios() and change the comments which reference it. [akpm@linux-foundation.org: remove unneeded `extern'] Link: https://lkml.kernel.org/r/20240412182139.120871-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Sidhartha Kumar | 54fa49b2e0 | mm/hugetlb: convert dissolve_free_huge_pages() to folios Allows us to rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folio(). Convert one caller to pass in a folio directly and use page_folio() to convert the caller in mm/memory-failure. [sidhartha.kumar@oracle.com: remove unneeded `extern'] Link: https://lkml.kernel.org/r/71760ed4-e80d-493a-95ea-2545414b1aba@oracle.com [sidhartha.kumar@oracle.com: v2] Link: https://lkml.kernel.org/r/20240412182139.120871-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20240411164756.261178-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Peter Xu | 9cb28da546 | mm/gup: handle hugetlb in the generic follow_page_mask code Now follow_page() is ready to handle hugetlb pages in whatever form, and over all architectures. Switch to the generic code path. Time to retire hugetlb_follow_page_mask(), following the previous retirement of follow_hugetlb_page() in | ||
|  Peter Xu | 24334e78e8 | mm/hugetlb: declare hugetlbfs_pagecache_present() non-static It will be used outside hugetlb.c soon. Link: https://lkml.kernel.org/r/20240327152332.950956-3-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Tested-by: Ryan Roberts <ryan.roberts@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Jones <andrew.jones@linux.dev> Cc: Aneesh Kumar K.V (IBM) <aneesh.kumar@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: James Houghton <jthoughton@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Rik van Riel <riel@surriel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Matthew Wilcox (Oracle) | 51718e25c5 | mm: convert arch_clear_hugepage_flags to take a folio All implementations that aren't no-ops just set a bit in the flags, and we want to use the folio flags rather than the page flags for that. Rename it to arch_clear_hugetlb_flags() while we're touching it so nobody thinks it's used for THP. [willy@infradead.org: fix arm64 build] Link: https://lkml.kernel.org/r/ZgQvNKGdlDkwhQEX@casper.infradead.org Link: https://lkml.kernel.org/r/20240326171045.410737-8-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Baolin Wang | 42d0c3fbb5 | mm: hugetlb: make the hugetlb migration strategy consistent As discussed in previous thread [1], there is an inconsistency when handing hugetlb migration. When handling the migration of freed hugetlb, it prevents fallback to other NUMA nodes in alloc_and_dissolve_hugetlb_folio(). However, when dealing with in-use hugetlb, it allows fallback to other NUMA nodes in alloc_hugetlb_folio_nodemask(), which can break the per-node hugetlb pool and might result in unexpected failures when node bound workloads doesn't get what is asssumed available. To make hugetlb migration strategy more clear, we should list all the scenarios of hugetlb migration and analyze whether allocation fallback is permitted: 1) Memory offline: will call dissolve_free_huge_pages() to free the freed hugetlb, and call do_migrate_range() to migrate the in-use hugetlb. Both can break the per-node hugetlb pool, but as this is an explicit offlining operation, no better choice. So should allow the hugetlb allocation fallback. 2) Memory failure: same as memory offline. Should allow fallback to a different node might be the only option to handle it, otherwise the impact of poisoned memory can be amplified. 3) Longterm pinning: will call migrate_longterm_unpinnable_pages() to migrate in-use and not-longterm-pinnable hugetlb, which can break the per-node pool. But we should fail to longterm pinning if can not allocate on current node to avoid breaking the per-node pool. 4) Syscalls (mbind, migrate_pages, move_pages): these are explicit users operation to move pages to other nodes, so fallback to other nodes should not be prohibited. 5) alloc_contig_range: used by CMA allocation and virtio-mem fake-offline to allocate given range of pages. Now the freed hugetlb migration is not allowed to fallback, to keep consistency, the in-use hugetlb migration should be also not allowed to fallback. 6) alloc_contig_pages: used by kfence, pgtable_debug etc. The strategy should be consistent with that of alloc_contig_range(). Based on the analysis of the various scenarios above, introducing a new helper to determine whether fallback is permitted according to the migration reason.. [1] https://lore.kernel.org/all/6f26ce22d2fcd523418a085f2c588fe0776d46e7.1706794035.git.baolin.wang@linux.alibaba.com/ Link: https://lkml.kernel.org/r/3519fcd41522817307a05b40fb551e2e17e68101.1709719720.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: David Hildenbrand <david@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Peter Xu | 9636f055da | mm/treewide: remove pXd_huge() This API is not used anymore, drop it for the whole tree. Link: https://lkml.kernel.org/r/20240318200404.448346-13-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bjorn Andersson <andersson@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Fabio Estevam <festevam@denx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Konrad Dybcio <konrad.dybcio@linaro.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Cc: Lucas Stach <l.stach@pengutronix.de> Cc: Mark Salter <msalter@redhat.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Matthew Wilcox (Oracle) | 886b94d25a | fs: Add FOP_HUGE_PAGES Instead of checking for specific file_operations, add a bit to file_operations which denotes a file that only contain hugetlb pages. This lets us make hugetlbfs_file_operations static, and removes is_file_shm_hugepages() completely. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20240407201122.3783877-1-willy@infradead.org Signed-off-by: Christian Brauner <brauner@kernel.org> | ||
|  Gang Li | b78b27d029 | hugetlb: parallelize 1G hugetlb initialization Optimizing the initialization speed of 1G huge pages through
parallelization.
1G hugetlbs are allocated from bootmem, a process that is already very
fast and does not currently require optimization.  Therefore, we focus on
parallelizing only the initialization phase in `gather_bootmem_prealloc`.
Here are some test results:
      test case       no patch(ms)   patched(ms)   saved
 ------------------- -------------- ------------- --------
  256c2T(4 node) 1G           4745          2024   57.34%
  128c1T(2 node) 1G           3358          1712   49.02%
     12T         1G          77000         18300   76.23%
[akpm@linux-foundation.org: s/initialied/initialized/, per Alexey]
Link: https://lkml.kernel.org/r/20240222140422.393911-9-gang.li@linux.dev
Signed-off-by: Gang Li <ligang.bdlg@bytedance.com>
Tested-by: David Rientjes <rientjes@google.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Kirill A. Shutemov | 5e0a760b44 | mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER commit  | ||
|  Mike Kravetz | 187da0f825 | hugetlb: fix null-ptr-deref in hugetlb_vma_lock_write The routine __vma_private_lock tests for the existence of a reserve map
associated with a private hugetlb mapping.  A pointer to the reserve map
is in vma->vm_private_data.  __vma_private_lock was checking the pointer
for NULL.  However, it is possible that the low bits of the pointer could
be used as flags.  In such instances, vm_private_data is not NULL and not
a valid pointer.  This results in the null-ptr-deref reported by syzbot:
general protection fault, probably for non-canonical address 0xdffffc000000001d:
 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef]
CPU: 0 PID: 5048 Comm: syz-executor139 Not tainted 6.6.0-rc7-syzkaller-00142-g88
8cf78c29e2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 1
0/09/2023
RIP: 0010:__lock_acquire+0x109/0x5de0 kernel/locking/lockdep.c:5004
...
Call Trace:
 <TASK>
 lock_acquire kernel/locking/lockdep.c:5753 [inline]
 lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718
 down_write+0x93/0x200 kernel/locking/rwsem.c:1573
 hugetlb_vma_lock_write mm/hugetlb.c:300 [inline]
 hugetlb_vma_lock_write+0xae/0x100 mm/hugetlb.c:291
 __hugetlb_zap_begin+0x1e9/0x2b0 mm/hugetlb.c:5447
 hugetlb_zap_begin include/linux/hugetlb.h:258 [inline]
 unmap_vmas+0x2f4/0x470 mm/memory.c:1733
 exit_mmap+0x1ad/0xa60 mm/mmap.c:3230
 __mmput+0x12a/0x4d0 kernel/fork.c:1349
 mmput+0x62/0x70 kernel/fork.c:1371
 exit_mm kernel/exit.c:567 [inline]
 do_exit+0x9ad/0x2a20 kernel/exit.c:861
 __do_sys_exit kernel/exit.c:991 [inline]
 __se_sys_exit kernel/exit.c:989 [inline]
 __x64_sys_exit+0x42/0x50 kernel/exit.c:989
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Mask off low bit flags before checking for NULL pointer.  In addition, the
reserve map only 'belongs' to the OWNER (parent in parent/child
relationships) so also check for the OWNER flag.
Link: https://lkml.kernel.org/r/20231114012033.259600-1-mike.kravetz@oracle.com
Reported-by: syzbot+6ada951e7c0f7bc8a71e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-mm/00000000000078d1e00608d7878b@google.com/
Fixes:  | ||
|  Hugh Dickins | 72e315f7a7 | mempolicy: mmap_lock is not needed while migrating folios mbind(2) holds down_write of current task's mmap_lock throughout (exclusive because it needs to set the new mempolicy on the vmas); migrate_pages(2) holds down_read of pid's mmap_lock throughout. They both hold mmap_lock across the internal migrate_pages(), under which all new page allocations (huge or small) are made. I'm nervous about it; and migrate_pages() certainly does not need mmap_lock itself. It's done this way for mbind(2), because its page allocator is vma_alloc_folio() or alloc_hugetlb_folio_vma(), both of which depend on vma and address. Now that we have alloc_pages_mpol(), depending on (refcounted) memory policy and interleave index, mbind(2) can be modified to use that or alloc_hugetlb_folio_nodemask(), and then not need mmap_lock across the internal migrate_pages() at all: add alloc_migration_target_by_mpol() to replace mbind's new_page(). (After that change, alloc_hugetlb_folio_vma() is used by nothing but a userfaultfd function: move it out of hugetlb.h and into the #ifdef.) migrate_pages(2) has chosen its target node before migrating, so can continue to use the standard alloc_migration_target(); but let it take and drop mmap_lock just around migrate_to_node()'s queue_pages_range(): neither the node-to-node calculations nor the page migrations need it. It seems unlikely, but it is conceivable that some userspace depends on the kernel's mmap_lock exclusion here, instead of doing its own locking: more likely in a testsuite than in real life. It is also possible, of course, that some pages on the list will be munmapped by another thread before they are migrated, or a newer memory policy applied to the range by that time: but such races could happen before, as soon as mmap_lock was dropped, so it does not appear to be a concern. Link: https://lkml.kernel.org/r/21e564e8-269f-6a89-7ee2-fd612831c289@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Hugh Dickins | 10969b5571 | hugetlbfs: drop shared NUMA mempolicy pretence Patch series "mempolicy: cleanups leading to NUMA mpol without vma", v2. Mostly cleanups in mm/mempolicy.c, but finally removing the pseudo-vma from shmem folio allocation, and removing the mmap_lock around folio migration for mbind and migrate_pages syscalls. This patch (of 12): hugetlbfs_fallocate() goes through the motions of pasting a shared NUMA mempolicy onto its pseudo-vma, but how could there ever be a shared NUMA mempolicy for this file? hugetlb_vm_ops has never offered a set_policy method, and hugetlbfs_parse_param() has never supported any mpol options for a mount-wide default policy. It's just an illusion: clean it away so as not to confuse others, giving us more freedom to adjust shmem's set_policy/get_policy implementation. But hugetlbfs_inode_info is still required, just to accommodate seals. Yes, shared NUMA mempolicy support could be added to hugetlbfs, with a set_policy method and/or mpol mount option (Andi's first posting did include an admitted-unsatisfactory hugetlb_set_policy()); but it seems that nobody has bothered to add that in the nineteen years since v2.6.7 made it possible, and there is at least one company that has invested enough into hugetlbfs, that I guess they have learnt well enough how to manage its NUMA, without needing shared mempolicy. Remove linux/mempolicy.h from linux/hugetlb.h: include linux/pagemap.h in its place, because hugetlb.h's recently added use of filemap_lock_folio() requires that (although most .configs and .c's get it in some other way). Link: https://lkml.kernel.org/r/ebc0987e-beff-8bfb-9283-234c2cbd17c5@google.com Link: https://lkml.kernel.org/r/cae82d4b-904a-faaf-282a-34fcc188c81f@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Muhammad Usama Anjum | 52526ca7fd | fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs The PAGEMAP_SCAN IOCTL on the pagemap file can be used to get or optionally clear the info about page table entries. The following operations are supported in this IOCTL: - Scan the address range and get the memory ranges matching the provided criteria. This is performed when the output buffer is specified. - Write-protect the pages. The PM_SCAN_WP_MATCHING is used to write-protect the pages of interest. The PM_SCAN_CHECK_WPASYNC aborts the operation if non-Async Write Protected pages are found. The ``PM_SCAN_WP_MATCHING`` can be used with or without PM_SCAN_CHECK_WPASYNC. - Both of those operations can be combined into one atomic operation where we can get and write protect the pages as well. Following flags about pages are currently supported: - PAGE_IS_WPALLOWED - Page has async-write-protection enabled - PAGE_IS_WRITTEN - Page has been written to from the time it was write protected - PAGE_IS_FILE - Page is file backed - PAGE_IS_PRESENT - Page is present in the memory - PAGE_IS_SWAPPED - Page is in swapped - PAGE_IS_PFNZERO - Page has zero PFN - PAGE_IS_HUGE - Page is THP or Hugetlb backed This IOCTL can be extended to get information about more PTE bits. The entire address range passed by user [start, end) is scanned until either the user provided buffer is full or max_pages have been found. [akpm@linux-foundation.org: update it for "mm: hugetlb: add huge page size param to set_huge_pte_at()"] [akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n warning] [arnd@arndb.de: hide unused pagemap_scan_backout_range() function] Link: https://lkml.kernel.org/r/20230927060257.2975412-1-arnd@kernel.org [sfr@canb.auug.org.au: fix "fs/proc/task_mmu: hide unused pagemap_scan_backout_range() function"] Link: https://lkml.kernel.org/r/20230928092223.0625c6bf@canb.auug.org.au Link: https://lkml.kernel.org/r/20230821141518.870589-3-usama.anjum@collabora.com Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Reviewed-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Cc: Alex Sierra <alex.sierra@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Miroslaw <emmir@google.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Paul Gofman <pgofman@codeweavers.com> Cc: Peter Xu <peterx@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <shy828301@gmail.com> Cc: Yun Zhou <yun.zhou@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Andrew Morton | 5ef8f1b2b4 | Merge mm-hotfixes-stable into mm-stable to pick up depended-upon changes. | ||
|  Rik van Riel | 2820b0f09b | hugetlbfs: close race between MADV_DONTNEED and page fault Malloc libraries, like jemalloc and tcalloc, take decisions on when to
call madvise independently from the code in the main application.
This sometimes results in the application page faulting on an address,
right after the malloc library has shot down the backing memory with
MADV_DONTNEED.
Usually this is harmless, because we always have some 4kB pages sitting
around to satisfy a page fault.  However, with hugetlbfs systems often
allocate only the exact number of huge pages that the application wants.
Due to TLB batching, hugetlbfs MADV_DONTNEED will free pages outside of
any lock taken on the page fault path, which can open up the following
race condition:
       CPU 1                            CPU 2
       MADV_DONTNEED
       unmap page
       shoot down TLB entry
                                       page fault
                                       fail to allocate a huge page
                                       killed with SIGBUS
       free page
Fix that race by pulling the locking from __unmap_hugepage_final_range
into helper functions called from zap_page_range_single.  This ensures
page faults stay locked out of the MADV_DONTNEED VMA until the huge pages
have actually been freed.
Link: https://lkml.kernel.org/r/20231006040020.3677377-4-riel@surriel.com
Fixes:  | ||
|  Rik van Riel | bf4916922c | hugetlbfs: extend hugetlb_vma_lock to private VMAs Extend the locking scheme used to protect shared hugetlb mappings from
truncate vs page fault races, in order to protect private hugetlb mappings
(with resv_map) against MADV_DONTNEED.
Add a read-write semaphore to the resv_map data structure, and use that
from the hugetlb_vma_(un)lock_* functions, in preparation for closing the
race between MADV_DONTNEED and page faults.
Link: https://lkml.kernel.org/r/20231006040020.3677377-3-riel@surriel.com
Fixes:  | ||
|  Sidhartha Kumar | a08c7193e4 | mm/filemap: remove hugetlb special casing in filemap.c Remove special cased hugetlb handling code within the page cache by
changing the granularity of ->index to the base page size rather than the
huge page size.  The motivation of this patch is to reduce complexity
within the filemap code while also increasing performance by removing
branches that are evaluated on every page cache lookup.
To support the change in index, new wrappers for hugetlb page cache
interactions are added.  These wrappers perform the conversion to a linear
index which is now expected by the page cache for huge pages.
========================= PERFORMANCE ======================================
Perf was used to check the performance differences after the patch. 
Overall the performance is similar to mainline with a very small larger
overhead that occurs in __filemap_add_folio() and
hugetlb_add_to_page_cache().  This is because of the larger overhead that
occurs in xa_load() and xa_store() as the xarray is now using more entries
to store hugetlb folios in the page cache.
Timing
aarch64
    2MB Page Size
        6.5-rc3 + this patch:
            [root@sidhakum-ol9-1 hugepages]# time fallocate -l 700GB test.txt
            real    1m49.568s
            user    0m0.000s
            sys     1m49.461s
        6.5-rc3:
            [root]# time fallocate -l 700GB test.txt
            real    1m47.495s
            user    0m0.000s
            sys     1m47.370s
    1GB Page Size
        6.5-rc3 + this patch:
            [root@sidhakum-ol9-1 hugepages1G]# time fallocate -l 700GB test.txt
            real    1m47.024s
            user    0m0.000s
            sys     1m46.921s
        6.5-rc3:
            [root@sidhakum-ol9-1 hugepages1G]# time fallocate -l 700GB test.txt
            real    1m44.551s
            user    0m0.000s
            sys     1m44.438s
x86
    2MB Page Size
        6.5-rc3 + this patch:
            [root@sidhakum-ol9-2 hugepages]# time fallocate -l 100GB test.txt
            real    0m22.383s
            user    0m0.000s
            sys     0m22.255s
        6.5-rc3:
            [opc@sidhakum-ol9-2 hugepages]$ time sudo fallocate -l 100GB /dev/hugepages/test.txt
            real    0m22.735s
            user    0m0.038s
            sys     0m22.567s
    1GB Page Size
        6.5-rc3 + this patch:
            [root@sidhakum-ol9-2 hugepages1GB]# time fallocate -l 100GB test.txt
            real    0m25.786s
            user    0m0.001s
            sys     0m25.589s
        6.5-rc3:
            [root@sidhakum-ol9-2 hugepages1G]# time fallocate -l 100GB test.txt
            real    0m33.454s
            user    0m0.001s
            sys     0m33.193s
aarch64:
    workload - fallocate a 700GB file backed by huge pages
    6.5-rc3 + this patch:
        2MB Page Size:
            --100.00%--__arm64_sys_fallocate
                          ksys_fallocate
                          vfs_fallocate
                          hugetlbfs_fallocate
                          |
                          |--95.04%--__pi_clear_page
                          |
                          |--3.57%--clear_huge_page
                          |          |
                          |          |--2.63%--rcu_all_qs
                          |          |
                          |           --0.91%--__cond_resched
                          |
                           --0.67%--__cond_resched
            0.17%     0.00%             0  fallocate  [kernel.vmlinux]       [k] hugetlb_add_to_page_cache
            0.14%     0.10%            11  fallocate  [kernel.vmlinux]       [k] __filemap_add_folio
    6.5-rc3
        2MB Page Size:
                --100.00%--__arm64_sys_fallocate
                          ksys_fallocate
                          vfs_fallocate
                          hugetlbfs_fallocate
                          |
                          |--94.91%--__pi_clear_page
                          |
                          |--4.11%--clear_huge_page
                          |          |
                          |          |--3.00%--rcu_all_qs
                          |          |
                          |           --1.10%--__cond_resched
                          |
                           --0.59%--__cond_resched
            0.08%     0.01%             1  fallocate  [kernel.kallsyms]  [k] hugetlb_add_to_page_cache
            0.05%     0.03%             3  fallocate  [kernel.kallsyms]  [k] __filemap_add_folio
x86
    workload - fallocate a 100GB file backed by huge pages
    6.5-rc3 + this patch:
        2MB Page Size:
            hugetlbfs_fallocate
            |
            --99.57%--clear_huge_page
                |
                --98.47%--clear_page_erms
                    |
                    --0.53%--asm_sysvec_apic_timer_interrupt
            0.04%     0.04%             1  fallocate  [kernel.kallsyms]     [k] xa_load
            0.04%     0.00%             0  fallocate  [kernel.kallsyms]     [k] hugetlb_add_to_page_cache
            0.04%     0.00%             0  fallocate  [kernel.kallsyms]     [k] __filemap_add_folio
            0.04%     0.00%             0  fallocate  [kernel.kallsyms]     [k] xas_store
    6.5-rc3
        2MB Page Size:
                --99.93%--__x64_sys_fallocate
                          vfs_fallocate
                          hugetlbfs_fallocate
                          |
                           --99.38%--clear_huge_page
                                     |
                                     |--98.40%--clear_page_erms
                                     |
                                      --0.59%--__cond_resched
            0.03%     0.03%             1  fallocate  [kernel.kallsyms]  [k] __filemap_add_folio
========================= TESTING ======================================
This patch passes libhugetlbfs tests and LTP hugetlb tests
********** TEST SUMMARY
*                      2M
*                      32-bit 64-bit
*     Total testcases:   110    113
*             Skipped:     0      0
*                PASS:   107    113
*                FAIL:     0      0
*    Killed by signal:     3      0
*   Bad configuration:     0      0
*       Expected FAIL:     0      0
*     Unexpected PASS:     0      0
*    Test not present:     0      0
* Strange test result:     0      0
**********
    Done executing testcases.
    LTP Version:  20220527-178-g2761a81c4
page migration was also tested using Mike Kravetz's test program.[8]
[dan.carpenter@linaro.org: fix an NULL vs IS_ERR() bug]
  Link: https://lkml.kernel.org/r/1772c296-1417-486f-8eef-171af2192681@moroto.mountain
Link: https://lkml.kernel.org/r/20230926192017.98183-1-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reported-and-tested-by: syzbot+c225dea486da4d5592bd@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c225dea486da4d5592bd
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> | ||
|  Ryan Roberts | 935d4f0c6d | mm: hugetlb: add huge page size param to set_huge_pte_at() Patch series "Fix set_huge_pte_at() panic on arm64", v2. This series fixes a bug in arm64's implementation of set_huge_pte_at(), which can result in an unprivileged user causing a kernel panic. The problem was triggered when running the new uffd poison mm selftest for HUGETLB memory. This test (and the uffd poison feature) was merged for v6.5-rc7. Ideally, I'd like to get this fix in for v6.6 and I've cc'ed stable (correctly this time) to get it backported to v6.5, where the issue first showed up. Description of Bug ================== arm64's huge pte implementation supports multiple huge page sizes, some of which are implemented in the page table with multiple contiguous entries. So set_huge_pte_at() needs to work out how big the logical pte is, so that it can also work out how many physical ptes (or pmds) need to be written. It previously did this by grabbing the folio out of the pte and querying its size. However, there are cases when the pte being set is actually a swap entry. But this also used to work fine, because for huge ptes, we only ever saw migration entries and hwpoison entries. And both of these types of swap entries have a PFN embedded, so the code would grab that and everything still worked out. But over time, more calls to set_huge_pte_at() have been added that set swap entry types that do not embed a PFN. And this causes the code to go bang. The triggering case is for the uffd poison test, commit |