linux-stable.git/Documentation/mm, branch v6.4 Linux kernel stable tree mm: page_table_check: Make it dependent on EXCLUSIVE_SYSTEM_RAM 2023-05-29T15:14:28+00:00 Ruihan Li lrh2000@pku.edu.cn 2023-05-15T13:09:57+00:00 81a31a860bb61d54eb688af2568d9332ed9b8942 Without EXCLUSIVE_SYSTEM_RAM, users are allowed to map arbitrary physical memory regions into the userspace via /dev/mem. At the same time, pages may change their properties (e.g., from anonymous pages to named pages) while they are still being mapped in the userspace, leading to "corruption" detected by the page table check. To avoid these false positives, this patch makes PAGE_TABLE_CHECK depends on EXCLUSIVE_SYSTEM_RAM. This dependency is understandable because PAGE_TABLE_CHECK is a hardening technique but /dev/mem without STRICT_DEVMEM (i.e., !EXCLUSIVE_SYSTEM_RAM) is itself a security problem. Even with EXCLUSIVE_SYSTEM_RAM, I/O pages may be still allowed to be mapped via /dev/mem. However, these pages are always considered as named pages, so they won't break the logic used in the page table check. Cc: <stable@vger.kernel.org> # 5.17 Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Pasha Tatashin <pasha.tatashin@soleen.com> Link: https://lore.kernel.org/r/20230515130958.32471-4-lrh2000@pku.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Without EXCLUSIVE_SYSTEM_RAM, users are allowed to map arbitrary
physical memory regions into the userspace via /dev/mem. At the same
time, pages may change their properties (e.g., from anonymous pages to
named pages) while they are still being mapped in the userspace, leading
to "corruption" detected by the page table check.

To avoid these false positives, this patch makes PAGE_TABLE_CHECK
depends on EXCLUSIVE_SYSTEM_RAM. This dependency is understandable
because PAGE_TABLE_CHECK is a hardening technique but /dev/mem without
STRICT_DEVMEM (i.e., !EXCLUSIVE_SYSTEM_RAM) is itself a security
problem.

Even with EXCLUSIVE_SYSTEM_RAM, I/O pages may be still allowed to be
mapped via /dev/mem. However, these pages are always considered as named
pages, so they won't break the logic used in the page table check.

Cc: <stable@vger.kernel.org> # 5.17
Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/r/20230515130958.32471-4-lrh2000@pku.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 2023-04-28T02:42:02+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-04-28T02:42:02+00:00 7fa8a8ee9400fe8ec188426e40e481717bc5e924 Pull MM updates from Andrew Morton: - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of switching from a user process to a kernel thread. - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav. - zsmalloc performance improvements from Sergey Senozhatsky. - Yue Zhao has found and fixed some data race issues around the alteration of memcg userspace tunables. - VFS rationalizations from Christoph Hellwig: - removal of most of the callers of write_one_page() - make __filemap_get_folio()'s return value more useful - Luis Chamberlain has changed tmpfs so it no longer requires swap backing. Use `mount -o noswap'. - Qi Zheng has made the slab shrinkers operate locklessly, providing some scalability benefits. - Keith Busch has improved dmapool's performance, making part of its operations O(1) rather than O(n). - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd, permitting userspace to wr-protect anon memory unpopulated ptes. - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather than exclusive, and has fixed a bunch of errors which were caused by its unintuitive meaning. - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature, which causes minor faults to install a write-protected pte. - Vlastimil Babka has done some maintenance work on vma_merge(): cleanups to the kernel code and improvements to our userspace test harness. - Cleanups to do_fault_around() by Lorenzo Stoakes. - Mike Rapoport has moved a lot of initialization code out of various mm/ files and into mm/mm_init.c. - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for DRM, but DRM doesn't use it any more. - Lorenzo has also coverted read_kcore() and vread() to use iterators and has thereby removed the use of bounce buffers in some cases. - Lorenzo has also contributed further cleanups of vma_merge(). - Chaitanya Prakash provides some fixes to the mmap selftesting code. - Matthew Wilcox changes xfs and afs so they no longer take sleeping locks in ->map_page(), a step towards RCUification of pagefaults. - Suren Baghdasaryan has improved mmap_lock scalability by switching to per-VMA locking. - Frederic Weisbecker has reworked the percpu cache draining so that it no longer causes latency glitches on cpu isolated workloads. - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig logic. - Liu Shixin has changed zswap's initialization so we no longer waste a chunk of memory if zswap is not being used. - Yosry Ahmed has improved the performance of memcg statistics flushing. - David Stevens has fixed several issues involving khugepaged, userfaultfd and shmem. - Christoph Hellwig has provided some cleanup work to zram's IO-related code paths. - David Hildenbrand has fixed up some issues in the selftest code's testing of our pte state changing. - Pankaj Raghav has made page_endio() unneeded and has removed it. - Peter Xu contributed some rationalizations of the userfaultfd selftests. - Yosry Ahmed has fixed an issue around memcg's page recalim accounting. - Chaitanya Prakash has fixed some arm-related issues in the selftests/mm code. - Longlong Xia has improved the way in which KSM handles hwpoisoned pages. - Peter Xu fixes a few issues with uffd-wp at fork() time. - Stefan Roesch has changed KSM so that it may now be used on a per-process and per-cgroup basis. * tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm,unmap: avoid flushing TLB in batch if PTE is inaccessible shmem: restrict noswap option to initial user namespace mm/khugepaged: fix conflicting mods to collapse_file() sparse: remove unnecessary 0 values from rc mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area() hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() maple_tree: fix allocation in mas_sparse_area() mm: do not increment pgfault stats when page fault handler retries zsmalloc: allow only one active pool compaction context selftests/mm: add new selftests for KSM mm: add new KSM process and sysfs knobs mm: add new api to enable ksm per process mm: shrinkers: fix debugfs file permissions mm: don't check VMA write permissions if the PTE/PMD indicates write permissions migrate_pages_batch: fix statistics for longterm pin retry userfaultfd: use helper function range_in_vma() lib/show_mem.c: use for_each_populated_zone() simplify code mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() fs/buffer: convert create_page_buffers to folio_create_buffers fs/buffer: add folio_create_empty_buffers helper ... 
Pull MM updates from Andrew Morton:

 - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
   switching from a user process to a kernel thread.

 - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
   Raghav.

 - zsmalloc performance improvements from Sergey Senozhatsky.

 - Yue Zhao has found and fixed some data race issues around the
   alteration of memcg userspace tunables.

 - VFS rationalizations from Christoph Hellwig:
     - removal of most of the callers of write_one_page()
     - make __filemap_get_folio()'s return value more useful

 - Luis Chamberlain has changed tmpfs so it no longer requires swap
   backing. Use `mount -o noswap'.

 - Qi Zheng has made the slab shrinkers operate locklessly, providing
   some scalability benefits.

 - Keith Busch has improved dmapool's performance, making part of its
   operations O(1) rather than O(n).

 - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
   permitting userspace to wr-protect anon memory unpopulated ptes.

 - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
   rather than exclusive, and has fixed a bunch of errors which were
   caused by its unintuitive meaning.

 - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
   which causes minor faults to install a write-protected pte.

 - Vlastimil Babka has done some maintenance work on vma_merge():
   cleanups to the kernel code and improvements to our userspace test
   harness.

 - Cleanups to do_fault_around() by Lorenzo Stoakes.

 - Mike Rapoport has moved a lot of initialization code out of various
   mm/ files and into mm/mm_init.c.

 - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
   DRM, but DRM doesn't use it any more.

 - Lorenzo has also coverted read_kcore() and vread() to use iterators
   and has thereby removed the use of bounce buffers in some cases.

 - Lorenzo has also contributed further cleanups of vma_merge().

 - Chaitanya Prakash provides some fixes to the mmap selftesting code.

 - Matthew Wilcox changes xfs and afs so they no longer take sleeping
   locks in ->map_page(), a step towards RCUification of pagefaults.

 - Suren Baghdasaryan has improved mmap_lock scalability by switching to
   per-VMA locking.

 - Frederic Weisbecker has reworked the percpu cache draining so that it
   no longer causes latency glitches on cpu isolated workloads.

 - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
   logic.

 - Liu Shixin has changed zswap's initialization so we no longer waste a
   chunk of memory if zswap is not being used.

 - Yosry Ahmed has improved the performance of memcg statistics
   flushing.

 - David Stevens has fixed several issues involving khugepaged,
   userfaultfd and shmem.

 - Christoph Hellwig has provided some cleanup work to zram's IO-related
   code paths.

 - David Hildenbrand has fixed up some issues in the selftest code's
   testing of our pte state changing.

 - Pankaj Raghav has made page_endio() unneeded and has removed it.

 - Peter Xu contributed some rationalizations of the userfaultfd
   selftests.

 - Yosry Ahmed has fixed an issue around memcg's page recalim
   accounting.

 - Chaitanya Prakash has fixed some arm-related issues in the
   selftests/mm code.

 - Longlong Xia has improved the way in which KSM handles hwpoisoned
   pages.

 - Peter Xu fixes a few issues with uffd-wp at fork() time.

 - Stefan Roesch has changed KSM so that it may now be used on a
   per-process and per-cgroup basis.

* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
  shmem: restrict noswap option to initial user namespace
  mm/khugepaged: fix conflicting mods to collapse_file()
  sparse: remove unnecessary 0 values from rc
  mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
  hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
  maple_tree: fix allocation in mas_sparse_area()
  mm: do not increment pgfault stats when page fault handler retries
  zsmalloc: allow only one active pool compaction context
  selftests/mm: add new selftests for KSM
  mm: add new KSM process and sysfs knobs
  mm: add new api to enable ksm per process
  mm: shrinkers: fix debugfs file permissions
  mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
  migrate_pages_batch: fix statistics for longterm pin retry
  userfaultfd: use helper function range_in_vma()
  lib/show_mem.c: use for_each_populated_zone() simplify code
  mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
  fs/buffer: convert create_page_buffers to folio_create_buffers
  fs/buffer: add folio_create_empty_buffers helper
  ...
Merge tag 'docs-6.4' of git://git.lwn.net/linux 2023-04-24T19:35:49+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-04-24T19:35:49+00:00 c23f28975abc2eb02cecc8bc1f2c95473a59ed2e Pull documentation updates from Jonathan Corbet: "Commit volume in documentation is relatively low this time, but there is still a fair amount going on, including: - Reorganize the architecture-specific documentation under Documentation/arch This makes the structure match the source directory and helps to clean up the mess that is the top-level Documentation directory a bit. This work creates the new directory and moves x86 and most of the less-active architectures there. The current plan is to move the rest of the architectures in 6.5, with the patches going through the appropriate subsystem trees. - Some more Spanish translations and maintenance of the Italian translation - A new "Kernel contribution maturity model" document from Ted - A new tutorial on quickly building a trimmed kernel from Thorsten Plus the usual set of updates and fixes" * tag 'docs-6.4' of git://git.lwn.net/linux: (47 commits) media: Adjust column width for pdfdocs media: Fix building pdfdocs docs: clk: add documentation to log which clocks have been disabled docs: trace: Fix typo in ftrace.rst Documentation/process: always CC responsible lists docs: kmemleak: adjust to config renaming ELF: document some de-facto PT_* ABI quirks Documentation: arm: remove stih415/stih416 related entries docs: turn off "smart quotes" in the HTML build Documentation: firmware: Clarify firmware path usage docs/mm: Physical Memory: Fix grammar Documentation: Add document for false sharing dma-api-howto: typo fix docs: move m68k architecture documentation under Documentation/arch/ docs: move parisc documentation under Documentation/arch/ docs: move ia64 architecture docs under Documentation/arch/ docs: Move arc architecture docs under Documentation/arch/ docs: move nios2 documentation under Documentation/arch/ docs: move openrisc documentation under Documentation/arch/ docs: move superh documentation under Documentation/arch/ ... 
Pull documentation updates from Jonathan Corbet:
 "Commit volume in documentation is relatively low this time, but there
  is still a fair amount going on, including:

   - Reorganize the architecture-specific documentation under
     Documentation/arch

     This makes the structure match the source directory and helps to
     clean up the mess that is the top-level Documentation directory a
     bit. This work creates the new directory and moves x86 and most of
     the less-active architectures there.

     The current plan is to move the rest of the architectures in 6.5,
     with the patches going through the appropriate subsystem trees.

   - Some more Spanish translations and maintenance of the Italian
     translation

   - A new "Kernel contribution maturity model" document from Ted

   - A new tutorial on quickly building a trimmed kernel from Thorsten

  Plus the usual set of updates and fixes"

* tag 'docs-6.4' of git://git.lwn.net/linux: (47 commits)
  media: Adjust column width for pdfdocs
  media: Fix building pdfdocs
  docs: clk: add documentation to log which clocks have been disabled
  docs: trace: Fix typo in ftrace.rst
  Documentation/process: always CC responsible lists
  docs: kmemleak: adjust to config renaming
  ELF: document some de-facto PT_* ABI quirks
  Documentation: arm: remove stih415/stih416 related entries
  docs: turn off "smart quotes" in the HTML build
  Documentation: firmware: Clarify firmware path usage
  docs/mm: Physical Memory: Fix grammar
  Documentation: Add document for false sharing
  dma-api-howto: typo fix
  docs: move m68k architecture documentation under Documentation/arch/
  docs: move parisc documentation under Documentation/arch/
  docs: move ia64 architecture docs under Documentation/arch/
  docs: Move arc architecture docs under Documentation/arch/
  docs: move nios2 documentation under Documentation/arch/
  docs: move openrisc documentation under Documentation/arch/
  docs: move superh documentation under Documentation/arch/
  ...
sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes 2023-04-16T19:31:58+00:00 Andrew Morton akpm@linux-foundation.org 2023-04-16T19:31:58+00:00 e492cd61b986590a45c674ede7dd1c4dbf94cf24 






docs/mm: Physical Memory: Fix grammar
2023-04-11T22:16:50+00:00

Kim Phillips
kim.phillips@amd.com

2023-03-31T16:52:54+00:00

7332f9e45d2e13fa93acd16e2e3f122a765ff965

it's -> its
referenced to by -> referenced by

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Link: https://lore.kernel.org/r/20230331165254.207526-1-kim.phillips@amd.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>





it's -> its
referenced to by -> referenced by

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Link: https://lore.kernel.org/r/20230331165254.207526-1-kim.phillips@amd.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>







zsmalloc: document freeable stats
2023-04-06T01:06:23+00:00

Sergey Senozhatsky
senozhatsky@chromium.org

2023-03-25T02:46:31+00:00

618a8a917dbf5830e2064d2fa0568940eb5d2584

When freeable class stat was added to classes file (back in 2016) we
forgot to update zsmalloc documentation.  Fix that.

Link: https://lkml.kernel.org/r/20230325024631.2817153-3-senozhatsky@chromium.org
Fixes: 1120ed548394 ("mm/zsmalloc: add `freeable' column to pool stat")
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>





When freeable class stat was added to classes file (back in 2016) we
forgot to update zsmalloc documentation.  Fix that.

Link: https://lkml.kernel.org/r/20230325024631.2817153-3-senozhatsky@chromium.org
Fixes: 1120ed548394 ("mm/zsmalloc: add `freeable' column to pool stat")
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>







zsmalloc: document new fullness grouping
2023-04-06T01:06:23+00:00

Sergey Senozhatsky
senozhatsky@chromium.org

2023-03-25T02:46:30+00:00

119b57eaf09478ce9e2a8f88a12749c2658b0ed5

Patch series "zsmalloc: minor documentation updates".

Two minor patches that bring zsmalloc documentation up to date.


This patch (of 2):

Update documentation and reflect new zspages fullness grouping (we don't
use almost_empty and almost_full anymore).

Link: https://lkml.kernel.org/r/20230325024631.2817153-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20230325024631.2817153-2-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Fixes: 67e157eb3639 ("zsmalloc: show per fullness group class stats")
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>





Patch series "zsmalloc: minor documentation updates".

Two minor patches that bring zsmalloc documentation up to date.


This patch (of 2):

Update documentation and reflect new zspages fullness grouping (we don't
use almost_empty and almost_full anymore).

Link: https://lkml.kernel.org/r/20230325024631.2817153-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20230325024631.2817153-2-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Fixes: 67e157eb3639 ("zsmalloc: show per fullness group class stats")
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>







shmem: add support to ignore swap
2023-03-28T23:20:15+00:00

Luis Chamberlain
mcgrof@kernel.org

2023-03-09T23:05:45+00:00

2c6efe9cf2d7841b75fe38ed1adbd41a90f51ba0

In doing experimentations with shmem having the option to avoid swap
becomes a useful mechanism.  One of the *raves* about brd over shmem is
you can avoid swap, but that's not really a good reason to use brd if we
can instead use shmem.  Using brd has its own good reasons to exist, but
just because "tmpfs" doesn't let you do that is not a great reason to
avoid it if we can easily add support for it.

I don't add support for reconfiguring incompatible options, but if we
really wanted to we can add support for that.

To avoid swap we use mapping_set_unevictable() upon inode creation, and
put a WARN_ON_ONCE() stop-gap on writepages() for reclaim.

Link: https://lkml.kernel.org/r/20230309230545.2930737-7-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Adam Manzanares <a.manzanares@samsung.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>





In doing experimentations with shmem having the option to avoid swap
becomes a useful mechanism.  One of the *raves* about brd over shmem is
you can avoid swap, but that's not really a good reason to use brd if we
can instead use shmem.  Using brd has its own good reasons to exist, but
just because "tmpfs" doesn't let you do that is not a great reason to
avoid it if we can easily add support for it.

I don't add support for reconfiguring incompatible options, but if we
really wanted to we can add support for that.

To avoid swap we use mapping_set_unevictable() upon inode creation, and
put a WARN_ON_ONCE() stop-gap on writepages() for reclaim.

Link: https://lkml.kernel.org/r/20230309230545.2930737-7-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Adam Manzanares <a.manzanares@samsung.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>







mm/debug_vm_pgtable: replace pte_mkhuge() with arch_make_huge_pte()
2023-03-28T23:20:11+00:00

Anshuman Khandual
anshuman.khandual@arm.com

2023-03-02T11:48:45+00:00

9dabf6e1374519f89d9fc326a129b5cc35088479

Since the following commit arch_make_huge_pte() should be used directly in
generic memory subsystem as a platform provided page table helper, instead
of pte_mkhuge().  Change hugetlb_basic_tests() to call
arch_make_huge_pte() directly, and update its relevant documentation entry
as required.

'commit 16785bd77431 ("mm: merge pte_mkhuge() call into arch_make_huge_pte()")'

Link: https://lkml.kernel.org/r/20230302114845.421674-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
  Link: https://lore.kernel.org/all/1ea45095-0926-a56a-a273-816709e9075e@csgroup.eu/
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>





Since the following commit arch_make_huge_pte() should be used directly in
generic memory subsystem as a platform provided page table helper, instead
of pte_mkhuge().  Change hugetlb_basic_tests() to call
arch_make_huge_pte() directly, and update its relevant documentation entry
as required.

'commit 16785bd77431 ("mm: merge pte_mkhuge() call into arch_make_huge_pte()")'

Link: https://lkml.kernel.org/r/20230302114845.421674-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
  Link: https://lore.kernel.org/all/1ea45095-0926-a56a-a273-816709e9075e@csgroup.eu/
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>







lazy tlb: allow lazy tlb mm refcounting to be configurable
2023-03-28T23:20:08+00:00

Nicholas Piggin
npiggin@gmail.com

2023-02-03T07:18:35+00:00

88e3009b5283bbd41447f0352d0b9df16cf6f183

Add CONFIG_MMU_TLB_REFCOUNT which enables refcounting of the lazy tlb mm
when it is context switched.  This can be disabled by architectures that
don't require this refcounting if they clean up lazy tlb mms when the last
refcount is dropped.  Currently this is always enabled, so the patch
introduces no functional change.

Link: https://lkml.kernel.org/r/20230203071837.1136453-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>





Add CONFIG_MMU_TLB_REFCOUNT which enables refcounting of the lazy tlb mm
when it is context switched.  This can be disabled by architectures that
don't require this refcounting if they clean up lazy tlb mms when the last
refcount is dropped.  Currently this is always enabled, so the patch
introduces no functional change.

Link: https://lkml.kernel.org/r/20230203071837.1136453-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>