linux-toradex.git/fs/exec.c, branch v6.1-rc3

Merge tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-30T00:49:33+00:00

Pull misc hotfixes from Andrew Morton:
 "Eight fix pre-6.0 bugs and the remainder address issues which were
  introduced in the 6.1-rc merge cycle, or address issues which aren't
  considered sufficiently serious to warrant a -stable backport"

* tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits)
  mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region
  lib: maple_tree: remove unneeded initialization in mtree_range_walk()
  mmap: fix remap_file_pages() regression
  mm/shmem: ensure proper fallback if page faults
  mm/userfaultfd: replace kmap/kmap_atomic() with kmap_local_page()
  x86: fortify: kmsan: fix KMSAN fortify builds
  x86: asm: make sure __put_user_size() evaluates pointer once
  Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default
  x86/purgatory: disable KMSAN instrumentation
  mm: kmsan: export kmsan_copy_page_meta()
  mm: migrate: fix return value if all subpages of THPs are migrated successfully
  mm/uffd: fix vma check on userfault for wp
  mm: prep_compound_tail() clear page->private
  mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs
  mm/page_isolation: fix clang deadcode warning
  fs/ext4/super.c: remove unused `deprecated_msg'
  ipc/msg.c: fix percpu_counter use after free
  memory tier, sysfs: rename attribute "nodes" to "nodelist"
  MAINTAINERS: git://github.com -> https://github.com for nilfs2
  mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops
  ...

mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region

2022-10-28T20:37:23+00:00

lru_gen_add_mm() has been added within an IRQ-off region in the commit
mentioned below.  The other invocations of lru_gen_add_mm() are not within
an IRQ-off region.

The invocation within IRQ-off region is problematic on PREEMPT_RT because
the function is using a spin_lock_t which must not be used within
IRQ-disabled regions.

The other invocations of lru_gen_add_mm() occur while
task_struct::alloc_lock is acquired.  Move lru_gen_add_mm() after
interrupts are enabled and before task_unlock().

Link: https://lkml.kernel.org/r/20221026134830.711887-1-bigeasy@linutronix.de
Fixes: bd74fdaea1460 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Sebastian Andrzej Siewior 
Acked-by: Yu Zhao 
Cc: Al Viro 
Cc: "Eric W . Biederman" 
Cc: Kees Cook 
Cc: Thomas Gleixner 
Signed-off-by: Andrew Morton

exec: Copy oldsighand->action under spin-lock

2022-10-25T22:05:58+00:00

unshare_sighand should only access oldsighand->action
while holding oldsighand->siglock, to make sure that
newsighand->action is in a consistent state.

Signed-off-by: Bernd Edlinger 
Cc: stable@vger.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/AM8PR10MB470871DEBD1DED081F9CC391E4389@AM8PR10MB4708.EURPRD10.PROD.OUTLOOK.COM

Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-11T00:53:04+00:00

Pull MM updates from Andrew Morton:

- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
linux-next for a couple of months without, to my knowledge, any
negative reports (or any positive ones, come to that).

- Also the Maple Tree from Liam Howlett. An overlapping range-based
tree for vmas. It it apparently slightly more efficient in its own
right, but is mainly targeted at enabling work to reduce mmap_lock
contention.

Liam has identified a number of other tree users in the kernel which
could be beneficially onverted to mapletrees.

Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
at [1]. This has yet to be addressed due to Liam's unfortunately
timed vacation. He is now back and we'll get this fixed up.

- Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
clang-generated instrumentation to detect used-unintialized bugs down
to the single bit level.

KMSAN keeps finding bugs. New ones, as well as the legacy ones.

- Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
memory into THPs.

- Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
support file/shmem-backed pages.

- userfaultfd updates from Axel Rasmussen

- zsmalloc cleanups from Alexey Romanov

- cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
memory-failure

- Huang Ying adds enhancements to NUMA balancing memory tiering mode's
page promotion, with a new way of detecting hot pages.

- memcg updates from Shakeel Butt: charging optimizations and reduced
memory consumption.

- memcg cleanups from Kairui Song.

- memcg fixes and cleanups from Johannes Weiner.

- Vishal Moola provides more folio conversions

- Zhang Yi removed ll_rw_block() :(

- migration enhancements from Peter Xu

- migration error-path bugfixes from Huang Ying

- Aneesh Kumar added ability for a device driver to alter the memory
tiering promotion paths. For optimizations by PMEM drivers, DRM
drivers, etc.

- vma merging improvements from Jakub Matěn.

- NUMA hinting cleanups from David Hildenbrand.

- xu xin added aditional userspace visibility into KSM merging
activity.

- THP & KSM code consolidation from Qi Zheng.

- more folio work from Matthew Wilcox.

- KASAN updates from Andrey Konovalov.

- DAMON cleanups from Kaixu Xia.

- DAMON work from SeongJae Park: fixes, cleanups.

- hugetlb sysfs cleanups from Muchun Song.

- Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
hugetlb: allocate vma lock for all sharable vmas
hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer
hugetlb: fix vma lock handling during split vma and range unmapping
mglru: mm/vmscan.c: fix imprecise comments
mm/mglru: don't sync disk for each aging cycle
mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
mm: memcontrol: use do_memsw_account() in a few more places
mm: memcontrol: deprecate swapaccounting=0 mode
mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
mm/secretmem: remove reduntant return value
mm/hugetlb: add available_huge_pages() func
mm: remove unused inline functions from include/linux/mm_inline.h
selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
selftests/vm: add thp collapse shmem testing
selftests/vm: add thp collapse file and tmpfs testing
selftests/vm: modularize thp collapse memory operations
selftests/vm: dedup THP helpers
mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
mm/madvise: add file and shmem support to MADV_COLLAPSE
...

Merge tag 'ucount-rlimits-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2022-10-09T23:24:05+00:00

Pull ucounts update from Eric Biederman:
 "Split rlimit and ucount values and max values

  After the ucount rlimit code was merged a bunch of small but
  siginificant bugs were found and fixed. At the time it was realized
  that part of the problem was that while the ucount rlimits were very
  similar to the oridinary ucounts (in being nested counts with limits)
  the semantics were slightly different and the code would be less error
  prone if there was less sharing.

  This is the long awaited cleanup that should hopefully keep things
  more comprehensible and less error prone for whoever needs to touch
  that code next"

* tag 'ucount-rlimits-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ucounts: Split rlimit and ucount values and max values

Merge tag 'pull-file_inode' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-10-07T00:22:11+00:00

Pull file_inode() updates from Al Vrio:
 "whack-a-mole: cropped up open-coded file_inode() uses..."

* tag 'pull-file_inode' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  orangefs: use ->f_mapping
  _nfs42_proc_copy(): use ->f_mapping instead of file_inode()->i_mapping
  dma_buf: no need to bother with file_inode()->i_mapping
  nfs_finish_open(): don't open-code file_inode()
  bprm_fill_uid(): don't open-code file_inode()
  sgx: use ->f_mapping...
  exfat_iterate(): don't open-code file_inode(file)
  ibmvmc: don't open-code file_inode()

a.out: Remove the a.out implementation

2022-09-27T14:11:02+00:00

In commit 19e8b701e258 ("a.out: Stop building a.out/osf1 support on
alpha and m68k") the last users of a.out were disabled.

As nothing has turned up to cause this change to be reverted, let's
remove the code implementing a.out support as well.

There may be userspace users of the uapi bits left so the uapi
headers have been left untouched.

Signed-off-by: "Eric W. Biederman" 
Acked-by: Arnd Bergmann  # arm defconfigs
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/871qrx3hq3.fsf@email.froward.int.ebiederm.org

exec: use VMA iterator instead of linked list

2022-09-27T02:46:21+00:00

Remove a use of the vm_next list by doing the initial lookup with the VMA
iterator and then using it to find the next entry.

Link: https://lkml.kernel.org/r/20220906194824.2110408-42-Liam.Howlett@oracle.com
Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Liam R. Howlett 
Tested-by: Yu Zhao 
Cc: Catalin Marinas 
Cc: David Hildenbrand 
Cc: David Howells 
Cc: Davidlohr Bueso 
Cc: SeongJae Park 
Cc: Sven Schnelle 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

mm: remove vmacache

2022-09-27T02:46:18+00:00

By using the maple tree and the maple tree state, the vmacache is no
longer beneficial and is complicating the VMA code.  Remove the vmacache
to reduce the work in keeping it up to date and code complexity.

Link: https://lkml.kernel.org/r/20220906194824.2110408-26-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett 
Acked-by: Vlastimil Babka 
Tested-by: Yu Zhao 
Cc: Catalin Marinas 
Cc: David Hildenbrand 
Cc: David Howells 
Cc: Davidlohr Bueso 
Cc: "Matthew Wilcox (Oracle)" 
Cc: SeongJae Park 
Cc: Sven Schnelle 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

mm: multi-gen LRU: support page table walks

2022-09-27T02:46:09+00:00

To further exploit spatial locality, the aging prefers to walk page tables
to search for young PTEs and promote hot pages.  A kill switch will be
added in the next patch to disable this behavior.  When disabled, the
aging relies on the rmap only.

NB: this behavior has nothing similar with the page table scanning in the
2.4 kernel [1], which searches page tables for old PTEs, adds cold pages
to swapcache and unmaps them.

To avoid confusion, the term "iteration" specifically means the traversal
of an entire mm_struct list; the term "walk" will be applied to page
tables and the rmap, as usual.

An mm_struct list is maintained for each memcg, and an mm_struct follows
its owner task to the new memcg when this task is migrated.  Given an
lruvec, the aging iterates lruvec_memcg()->mm_list and calls
walk_page_range() with each mm_struct on this list to promote hot pages
before it increments max_seq.

When multiple page table walkers iterate the same list, each of them gets
a unique mm_struct; therefore they can run concurrently.  Page table
walkers ignore any misplaced pages, e.g., if an mm_struct was migrated,
pages it left in the previous memcg will not be promoted when its current
memcg is under reclaim.  Similarly, page table walkers will not promote
pages from nodes other than the one under reclaim.

This patch uses the following optimizations when walking page tables:
1. It tracks the usage of mm_struct's between context switches so that
   page table walkers can skip processes that have been sleeping since
   the last iteration.
2. It uses generational Bloom filters to record populated branches so
   that page table walkers can reduce their search space based on the
   query results, e.g., to skip page tables containing mostly holes or
   misplaced pages.
3. It takes advantage of the accessed bit in non-leaf PMD entries when
   CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y.
4. It does not zigzag between a PGD table and the same PMD table
   spanning multiple VMAs. IOW, it finishes all the VMAs within the
   range of the same PMD table before it returns to a PGD table. This
   improves the cache performance for workloads that have large
   numbers of tiny VMAs [2], especially when CONFIG_PGTABLE_LEVELS=5.

Server benchmark results:
  Single workload:
    fio (buffered I/O): no change

  Single workload:
    memcached (anon): +[8, 10]%
                Ops/sec      KB/sec
      patch1-7: 1147696.57   44640.29
      patch1-8: 1245274.91   48435.66

  Configurations:
    no change

Client benchmark results:
  kswapd profiles:
    patch1-7
      48.16%  lzo1x_1_do_compress (real work)
       8.20%  page_vma_mapped_walk (overhead)
       7.06%  _raw_spin_unlock_irq
       2.92%  ptep_clear_flush
       2.53%  __zram_bvec_write
       2.11%  do_raw_spin_lock
       2.02%  memmove
       1.93%  lru_gen_look_around
       1.56%  free_unref_page_list
       1.40%  memset

    patch1-8
      49.44%  lzo1x_1_do_compress (real work)
       6.19%  page_vma_mapped_walk (overhead)
       5.97%  _raw_spin_unlock_irq
       3.13%  get_pfn_folio
       2.85%  ptep_clear_flush
       2.42%  __zram_bvec_write
       2.08%  do_raw_spin_lock
       1.92%  memmove
       1.44%  alloc_zspage
       1.36%  memset

  Configurations:
    no change

Thanks to the following developers for their efforts [3].
  kernel test robot 

[1] https://lwn.net/Articles/23732/
[2] https://llvm.org/docs/ScudoHardenedAllocator.html
[3] https://lore.kernel.org/r/202204160827.ekEARWQo-lkp@intel.com/

Link: https://lkml.kernel.org/r/20220918080010.2920238-9-yuzhao@google.com
Signed-off-by: Yu Zhao 
Acked-by: Brian Geffon 
Acked-by: Jan Alexander Steffens (heftig) 
Acked-by: Oleksandr Natalenko 
Acked-by: Steven Barrett 
Acked-by: Suleiman Souhlal 
Tested-by: Daniel Byrne 
Tested-by: Donald Carr 
Tested-by: Holger Hoffstätte 
Tested-by: Konstantin Kharlamov 
Tested-by: Shuang Zhai 
Tested-by: Sofia Trinh 
Tested-by: Vaibhav Jain 
Cc: Andi Kleen 
Cc: Aneesh Kumar K.V 
Cc: Barry Song 
Cc: Catalin Marinas 
Cc: Dave Hansen 
Cc: Hillf Danton 
Cc: Jens Axboe 
Cc: Johannes Weiner 
Cc: Jonathan Corbet 
Cc: Linus Torvalds 
Cc: Matthew Wilcox 
Cc: Mel Gorman 
Cc: Miaohe Lin 
Cc: Michael Larabel 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Mike Rapoport 
Cc: Peter Zijlstra 
Cc: Qi Zheng 
Cc: Tejun Heo 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton