<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/mm/util.c, branch v5.19</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2022-05-28T18:27:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-05-28T18:27:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6112bd00e84e5dbffebc3c1e908cbe914ca772ee'/>
<id>6112bd00e84e5dbffebc3c1e908cbe914ca772ee</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)

 - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later)

 - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ

 - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later

 - Drop support for system call instruction emulation

 - Many other small features and fixes

Thanks to Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas
Sanjaya, Bjorn Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian
King, Daniel Axtens, Dwaipayan Ray, Fabiano Rosas, Finn Thain, Frank
Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu Hua, Haowen Bai,
Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing
Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof
Kozlowski, Laurent Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes,
Miaoqian Lin, Minghao Chi, Nathan Chancellor, Naveen N. Rao, Nicholas
Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár, Paul Mackerras,
Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib
Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang
wangx, Xiaomeng Tong, Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing,
Yu Kuai, Zheng Bin, Zou Wei, and Zucheng Zheng.

* tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits)
  powerpc/64: Include cache.h directly in paca.h
  powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU is set
  powerpc/xics: Include missing header
  powerpc/powernv/pci: Drop VF MPS fixup
  powerpc/fsl_book3e: Don't set rodata RO too early
  powerpc/microwatt: Add mmu bits to device tree
  powerpc/powernv/flash: Check OPAL flash calls exist before using
  powerpc/powermac: constify device_node in of_irq_parse_oldworld()
  powerpc/powermac: add missing g5_phy_disable_cpu1() declaration
  selftests/powerpc/pmu: fix spelling mistake "mis-match" -&gt; "mismatch"
  powerpc: Enable the DAWR on POWER9 DD2.3 and above
  powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask
  powerpc/64s: Add CPU_FTRS_POWER9_DD2_2 to CPU_FTRS_ALWAYS mask
  powerpc: Fix all occurences of "the the"
  selftests/powerpc/pmu/ebb: remove fixed_instruction.S
  powerpc/platforms/83xx: Use of_device_get_match_data()
  powerpc/eeh: Drop redundant spinlock initialization
  powerpc/iommu: Add missing of_node_put in iommu_init_early_dart
  powerpc/pseries/vas: Call misc_deregister if sysfs init fails
  powerpc/papr_scm: Fix leaking nvdimm_events_map elements
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:

 - Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)

 - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later)

 - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ

 - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later

 - Drop support for system call instruction emulation

 - Many other small features and fixes

Thanks to Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas
Sanjaya, Bjorn Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian
King, Daniel Axtens, Dwaipayan Ray, Fabiano Rosas, Finn Thain, Frank
Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu Hua, Haowen Bai,
Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing
Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof
Kozlowski, Laurent Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes,
Miaoqian Lin, Minghao Chi, Nathan Chancellor, Naveen N. Rao, Nicholas
Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár, Paul Mackerras,
Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib
Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang
wangx, Xiaomeng Tong, Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing,
Yu Kuai, Zheng Bin, Zou Wei, and Zucheng Zheng.

* tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits)
  powerpc/64: Include cache.h directly in paca.h
  powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU is set
  powerpc/xics: Include missing header
  powerpc/powernv/pci: Drop VF MPS fixup
  powerpc/fsl_book3e: Don't set rodata RO too early
  powerpc/microwatt: Add mmu bits to device tree
  powerpc/powernv/flash: Check OPAL flash calls exist before using
  powerpc/powermac: constify device_node in of_irq_parse_oldworld()
  powerpc/powermac: add missing g5_phy_disable_cpu1() declaration
  selftests/powerpc/pmu: fix spelling mistake "mis-match" -&gt; "mismatch"
  powerpc: Enable the DAWR on POWER9 DD2.3 and above
  powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask
  powerpc/64s: Add CPU_FTRS_POWER9_DD2_2 to CPU_FTRS_ALWAYS mask
  powerpc: Fix all occurences of "the the"
  selftests/powerpc/pmu/ebb: remove fixed_instruction.S
  powerpc/platforms/83xx: Use of_device_get_match_data()
  powerpc/eeh: Drop redundant spinlock initialization
  powerpc/iommu: Add missing of_node_put in iommu_init_early_dart
  powerpc/pseries/vas: Call misc_deregister if sysfs init fails
  powerpc/papr_scm: Fix leaking nvdimm_events_map elements
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-05-26T19:32:41+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-05-26T19:32:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=98931dd95fd489fcbfa97da563505a6f071d7c77'/>
<id>98931dd95fd489fcbfa97da563505a6f071d7c77</id>
<content type='text'>
Pull MM updates from Andrew Morton:
 "Almost all of MM here. A few things are still getting finished off,
  reviewed, etc.

   - Yang Shi has improved the behaviour of khugepaged collapsing of
     readonly file-backed transparent hugepages.

   - Johannes Weiner has arranged for zswap memory use to be tracked and
     managed on a per-cgroup basis.

   - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
     runtime enablement of the recent huge page vmemmap optimization
     feature.

   - Baolin Wang contributes a series to fix some issues around hugetlb
     pagetable invalidation.

   - Zhenwei Pi has fixed some interactions between hwpoisoned pages and
     virtualization.

   - Tong Tiangen has enabled the use of the presently x86-only
     page_table_check debugging feature on arm64 and riscv.

   - David Vernet has done some fixup work on the memcg selftests.

   - Peter Xu has taught userfaultfd to handle write protection faults
     against shmem- and hugetlbfs-backed files.

   - More DAMON development from SeongJae Park - adding online tuning of
     the feature and support for monitoring of fixed virtual address
     ranges. Also easier discovery of which monitoring operations are
     available.

   - Nadav Amit has done some optimization of TLB flushing during
     mprotect().

   - Neil Brown continues to labor away at improving our swap-over-NFS
     support.

   - David Hildenbrand has some fixes to anon page COWing versus
     get_user_pages().

   - Peng Liu fixed some errors in the core hugetlb code.

   - Joao Martins has reduced the amount of memory consumed by
     device-dax's compound devmaps.

   - Some cleanups of the arch-specific pagemap code from Anshuman
     Khandual.

   - Muchun Song has found and fixed some errors in the TLB flushing of
     transparent hugepages.

   - Roman Gushchin has done more work on the memcg selftests.

  ... and, of course, many smaller fixes and cleanups. Notably, the
  customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
  mm: kfence: use PAGE_ALIGNED helper
  selftests: vm: add the "settings" file with timeout variable
  selftests: vm: add "test_hmm.sh" to TEST_FILES
  selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
  selftests: vm: add migration to the .gitignore
  selftests/vm/pkeys: fix typo in comment
  ksm: fix typo in comment
  selftests: vm: add process_mrelease tests
  Revert "mm/vmscan: never demote for memcg reclaim"
  mm/kfence: print disabling or re-enabling message
  include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
  include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
  mm: fix a potential infinite loop in start_isolate_page_range()
  MAINTAINERS: add Muchun as co-maintainer for HugeTLB
  zram: fix Kconfig dependency warning
  mm/shmem: fix shmem folio swapoff hang
  cgroup: fix an error handling path in alloc_pagecache_max_30M()
  mm: damon: use HPAGE_PMD_SIZE
  tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
  nodemask.h: fix compilation error with GCC12
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MM updates from Andrew Morton:
 "Almost all of MM here. A few things are still getting finished off,
  reviewed, etc.

   - Yang Shi has improved the behaviour of khugepaged collapsing of
     readonly file-backed transparent hugepages.

   - Johannes Weiner has arranged for zswap memory use to be tracked and
     managed on a per-cgroup basis.

   - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
     runtime enablement of the recent huge page vmemmap optimization
     feature.

   - Baolin Wang contributes a series to fix some issues around hugetlb
     pagetable invalidation.

   - Zhenwei Pi has fixed some interactions between hwpoisoned pages and
     virtualization.

   - Tong Tiangen has enabled the use of the presently x86-only
     page_table_check debugging feature on arm64 and riscv.

   - David Vernet has done some fixup work on the memcg selftests.

   - Peter Xu has taught userfaultfd to handle write protection faults
     against shmem- and hugetlbfs-backed files.

   - More DAMON development from SeongJae Park - adding online tuning of
     the feature and support for monitoring of fixed virtual address
     ranges. Also easier discovery of which monitoring operations are
     available.

   - Nadav Amit has done some optimization of TLB flushing during
     mprotect().

   - Neil Brown continues to labor away at improving our swap-over-NFS
     support.

   - David Hildenbrand has some fixes to anon page COWing versus
     get_user_pages().

   - Peng Liu fixed some errors in the core hugetlb code.

   - Joao Martins has reduced the amount of memory consumed by
     device-dax's compound devmaps.

   - Some cleanups of the arch-specific pagemap code from Anshuman
     Khandual.

   - Muchun Song has found and fixed some errors in the TLB flushing of
     transparent hugepages.

   - Roman Gushchin has done more work on the memcg selftests.

  ... and, of course, many smaller fixes and cleanups. Notably, the
  customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
  mm: kfence: use PAGE_ALIGNED helper
  selftests: vm: add the "settings" file with timeout variable
  selftests: vm: add "test_hmm.sh" to TEST_FILES
  selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
  selftests: vm: add migration to the .gitignore
  selftests/vm/pkeys: fix typo in comment
  ksm: fix typo in comment
  selftests: vm: add process_mrelease tests
  Revert "mm/vmscan: never demote for memcg reclaim"
  mm/kfence: print disabling or re-enabling message
  include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
  include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
  mm: fix a potential infinite loop in start_isolate_page_range()
  MAINTAINERS: add Muchun as co-maintainer for HugeTLB
  zram: fix Kconfig dependency warning
  mm/shmem: fix shmem folio swapoff hang
  cgroup: fix an error handling path in alloc_pagecache_max_30M()
  mm: damon: use HPAGE_PMD_SIZE
  tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
  nodemask.h: fix compilation error with GCC12
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>random: move randomize_page() into mm where it belongs</title>
<updated>2022-05-19T14:54:15+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-05-14T11:59:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5ad7dd882e45d7fe432c32e896e2aaa0b21746ea'/>
<id>5ad7dd882e45d7fe432c32e896e2aaa0b21746ea</id>
<content type='text'>
randomize_page is an mm function. It is documented like one. It contains
the history of one. It has the naming convention of one. It looks
just like another very similar function in mm, randomize_stack_top().
And it has always been maintained and updated by mm people. There is no
need for it to be in random.c. In the "which shape does not look like
the other ones" test, pointing to randomize_page() is correct.

So move randomize_page() into mm/util.c, right next to the similar
randomize_stack_top() function.

This commit contains no actual code changes.

Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
randomize_page is an mm function. It is documented like one. It contains
the history of one. It has the naming convention of one. It looks
just like another very similar function in mm, randomize_stack_top().
And it has always been maintained and updated by mm people. There is no
need for it to be in random.c. In the "which shape does not look like
the other ones" test, pointing to randomize_page() is correct.

So move randomize_page() into mm/util.c, right next to the similar
randomize_stack_top() function.

This commit contains no actual code changes.

Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: create new mm/swap.h header file</title>
<updated>2022-05-10T01:20:47+00:00</updated>
<author>
<name>NeilBrown</name>
<email>neilb@suse.de</email>
</author>
<published>2022-05-10T01:20:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=014bb1de4fc17d54907d54418126a9a9736f4aff'/>
<id>014bb1de4fc17d54907d54418126a9a9736f4aff</id>
<content type='text'>
Patch series "MM changes to improve swap-over-NFS support".

Assorted improvements for swap-via-filesystem.

This is a resend of these patches, rebased on current HEAD.  The only
substantial changes is that swap_dirty_folio has replaced
swap_set_page_dirty.

Currently swap-via-fs (SWP_FS_OPS) doesn't work for any filesystem.  It
has previously worked for NFS but that broke a few releases back.  This
series changes to use a new -&gt;swap_rw rather than -&gt;readpage and
-&gt;direct_IO.  It also makes other improvements.

There is a companion series already in linux-next which fixes various
issues with NFS.  Once both series land, a final patch is needed which
changes NFS over to use -&gt;swap_rw.


This patch (of 10):

Many functions declared in include/linux/swap.h are only used within mm/

Create a new "mm/swap.h" and move some of these declarations there.
Remove the redundant 'extern' from the function declarations.

[akpm@linux-foundation.org: mm/memory-failure.c needs mm/swap.h]
Link: https://lkml.kernel.org/r/164859751830.29473.5309689752169286816.stgit@noble.brown
Link: https://lkml.kernel.org/r/164859778120.29473.11725907882296224053.stgit@noble.brown
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Tested-by: David Howells &lt;dhowells@redhat.com&gt;
Tested-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Cc: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Patch series "MM changes to improve swap-over-NFS support".

Assorted improvements for swap-via-filesystem.

This is a resend of these patches, rebased on current HEAD.  The only
substantial changes is that swap_dirty_folio has replaced
swap_set_page_dirty.

Currently swap-via-fs (SWP_FS_OPS) doesn't work for any filesystem.  It
has previously worked for NFS but that broke a few releases back.  This
series changes to use a new -&gt;swap_rw rather than -&gt;readpage and
-&gt;direct_IO.  It also makes other improvements.

There is a companion series already in linux-next which fixes various
issues with NFS.  Once both series land, a final patch is needed which
changes NFS over to use -&gt;swap_rw.


This patch (of 10):

Many functions declared in include/linux/swap.h are only used within mm/

Create a new "mm/swap.h" and move some of these declarations there.
Remove the redundant 'extern' from the function declarations.

[akpm@linux-foundation.org: mm/memory-failure.c needs mm/swap.h]
Link: https://lkml.kernel.org/r/164859751830.29473.5309689752169286816.stgit@noble.brown
Link: https://lkml.kernel.org/r/164859778120.29473.11725907882296224053.stgit@noble.brown
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Tested-by: David Howells &lt;dhowells@redhat.com&gt;
Tested-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Cc: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: Allow arch specific arch_randomize_brk() with CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT</title>
<updated>2022-05-05T12:11:56+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2022-04-09T17:17:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=723820f3f77dc9f7ffdceb076ebcf6a5b91d0a27'/>
<id>723820f3f77dc9f7ffdceb076ebcf6a5b91d0a27</id>
<content type='text'>
Commit e7142bf5d231 ("arm64, mm: make randomization selected by
generic topdown mmap layout") introduced a default version of
arch_randomize_brk() provided when
CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT is selected.

powerpc could select CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
but needs to provide its own arch_randomize_brk().

In order to allow that, define generic version of arch_randomize_brk()
as a __weak symbol.

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Acked-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b222f1ca06c850daf1b2f26afdb46c6dd97d21ba.1649523076.git.christophe.leroy@csgroup.eu

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit e7142bf5d231 ("arm64, mm: make randomization selected by
generic topdown mmap layout") introduced a default version of
arch_randomize_brk() provided when
CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT is selected.

powerpc could select CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
but needs to provide its own arch_randomize_brk().

In order to allow that, define generic version of arch_randomize_brk()
as a __weak symbol.

Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Acked-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/b222f1ca06c850daf1b2f26afdb46c6dd97d21ba.1649523076.git.christophe.leroy@csgroup.eu

</pre>
</div>
</content>
</entry>
<entry>
<title>kvmalloc: use vmalloc_huge for vmalloc allocations</title>
<updated>2022-04-24T17:05:38+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-04-22T18:41:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9becb688913023124464c5463b4389b3b293f0e7'/>
<id>9becb688913023124464c5463b4389b3b293f0e7</id>
<content type='text'>
Since commit 559089e0a93d ("vmalloc: replace VM_NO_HUGE_VMAP with
VM_ALLOW_HUGE_VMAP"), the use of hugepage mappings for vmalloc is an
opt-in strategy, because it caused a number of problems that weren't
noticed until x86 enabled it too.

One of the issues was fixed by Nick Piggin in commit 3b8000ae185c
("mm/vmalloc: huge vmalloc backing pages should be split rather than
compound"), but I'm still worried about page protection issues, and
VM_FLUSH_RESET_PERMS in particular.

However, like the hash table allocation case (commit f2edd118d02d:
"page_alloc: use vmalloc_huge for large system hash"), the use of
kvmalloc() should be safe from any such games, since the returned
pointer might be a SLUB allocation, and as such no user should
reasonably be using it in any odd ways.

We also know that the allocations are fairly large, since it falls back
to the vmalloc case only when a kmalloc() fails.  So using a hugepage
mapping seems both safe and relevant.

This patch does show a weakness in the opt-in strategy: since the opt-in
flag is in the 'vm_flags', not the usual gfp_t allocation flags, very
few of the usual interfaces actually expose it.

That's not much of an issue in this case that already used one of the
fairly specialized low-level vmalloc interfaces for the allocation, but
for a lot of other vmalloc() users that might want to opt in, it's going
to be very inconvenient.

We'll either have to fix any compatibility problems, or expose it in the
gfp flags (__GFP_COMP would have made a lot of sense) to allow normal
vmalloc() users to use hugepage mappings.  That said, the cases that
really matter were probably already taken care of by the hash tabel
allocation.

Link: https://lore.kernel.org/all/20220415164413.2727220-1-song@kernel.org/
Link: https://lore.kernel.org/all/CAHk-=whao=iosX1s5Z4SF-ZGa-ebAukJoAdUJFk5SPwnofV+Vg@mail.gmail.com/
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since commit 559089e0a93d ("vmalloc: replace VM_NO_HUGE_VMAP with
VM_ALLOW_HUGE_VMAP"), the use of hugepage mappings for vmalloc is an
opt-in strategy, because it caused a number of problems that weren't
noticed until x86 enabled it too.

One of the issues was fixed by Nick Piggin in commit 3b8000ae185c
("mm/vmalloc: huge vmalloc backing pages should be split rather than
compound"), but I'm still worried about page protection issues, and
VM_FLUSH_RESET_PERMS in particular.

However, like the hash table allocation case (commit f2edd118d02d:
"page_alloc: use vmalloc_huge for large system hash"), the use of
kvmalloc() should be safe from any such games, since the returned
pointer might be a SLUB allocation, and as such no user should
reasonably be using it in any odd ways.

We also know that the allocations are fairly large, since it falls back
to the vmalloc case only when a kmalloc() fails.  So using a hugepage
mapping seems both safe and relevant.

This patch does show a weakness in the opt-in strategy: since the opt-in
flag is in the 'vm_flags', not the usual gfp_t allocation flags, very
few of the usual interfaces actually expose it.

That's not much of an issue in this case that already used one of the
fairly specialized low-level vmalloc interfaces for the allocation, but
for a lot of other vmalloc() users that might want to opt in, it's going
to be very inconvenient.

We'll either have to fix any compatibility problems, or expose it in the
gfp flags (__GFP_COMP would have made a lot of sense) to allow normal
vmalloc() users to use hugepage mappings.  That said, the cases that
really matter were probably already taken care of by the hash tabel
allocation.

Link: https://lore.kernel.org/all/20220415164413.2727220-1-song@kernel.org/
Link: https://lore.kernel.org/all/CAHk-=whao=iosX1s5Z4SF-ZGa-ebAukJoAdUJFk5SPwnofV+Vg@mail.gmail.com/
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2022-03-24T18:58:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-24T18:58:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1ebdbeb03efe89f01f15df038a589077df3d21f5'/>
<id>1ebdbeb03efe89f01f15df038a589077df3d21f5</id>
<content type='text'>
Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Proper emulation of the OSLock feature of the debug architecture

   - Scalibility improvements for the MMU lock when dirty logging is on

   - New VMID allocator, which will eventually help with SVA in VMs

   - Better support for PMUs in heterogenous systems

   - PSCI 1.1 support, enabling support for SYSTEM_RESET2

   - Implement CONFIG_DEBUG_LIST at EL2

   - Make CONFIG_ARM64_ERRATUM_2077057 default y

   - Reduce the overhead of VM exit when no interrupt is pending

   - Remove traces of 32bit ARM host support from the documentation

   - Updated vgic selftests

   - Various cleanups, doc updates and spelling fixes

  RISC-V:
   - Prevent KVM_COMPAT from being selected

   - Optimize __kvm_riscv_switch_to() implementation

   - RISC-V SBI v0.3 support

  s390:
   - memop selftest

   - fix SCK locking

   - adapter interruptions virtualization for secure guests

   - add Claudio Imbrenda as maintainer

   - first step to do proper storage key checking

  x86:
   - Continue switching kvm_x86_ops to static_call(); introduce
     static_call_cond() and __static_call_ret0 when applicable.

   - Cleanup unused arguments in several functions

   - Synthesize AMD 0x80000021 leaf

   - Fixes and optimization for Hyper-V sparse-bank hypercalls

   - Implement Hyper-V's enlightened MSR bitmap for nested SVM

   - Remove MMU auditing

   - Eager splitting of page tables (new aka "TDP" MMU only) when dirty
     page tracking is enabled

   - Cleanup the implementation of the guest PGD cache

   - Preparation for the implementation of Intel IPI virtualization

   - Fix some segment descriptor checks in the emulator

   - Allow AMD AVIC support on systems with physical APIC ID above 255

   - Better API to disable virtualization quirks

   - Fixes and optimizations for the zapping of page tables:

      - Zap roots in two passes, avoiding RCU read-side critical
        sections that last too long for very large guests backed by 4
        KiB SPTEs.

      - Zap invalid and defunct roots asynchronously via
        concurrency-managed work queue.

      - Allowing yielding when zapping TDP MMU roots in response to the
        root's last reference being put.

      - Batch more TLB flushes with an RCU trick. Whoever frees the
        paging structure now holds RCU as a proxy for all vCPUs running
        in the guest, i.e. to prolongs the grace period on their behalf.
        It then kicks the the vCPUs out of guest mode before doing
        rcu_read_unlock().

  Generic:
   - Introduce __vcalloc and use it for very large allocations that need
     memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  KVM: use kvcalloc for array allocations
  KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
  kvm: x86: Require const tsc for RT
  KVM: x86: synthesize CPUID leaf 0x80000021h if useful
  KVM: x86: add support for CPUID leaf 0x80000021
  KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask
  Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
  kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU
  KVM: arm64: fix typos in comments
  KVM: arm64: Generalise VM features into a set of flags
  KVM: s390: selftests: Add error memop tests
  KVM: s390: selftests: Add more copy memop tests
  KVM: s390: selftests: Add named stages for memop test
  KVM: s390: selftests: Add macro as abstraction for MEM_OP
  KVM: s390: selftests: Split memop tests
  KVM: s390x: fix SCK locking
  RISC-V: KVM: Implement SBI HSM suspend call
  RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function
  RISC-V: Add SBI HSM suspend related defines
  RISC-V: KVM: Implement SBI v0.3 SRST extension
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Proper emulation of the OSLock feature of the debug architecture

   - Scalibility improvements for the MMU lock when dirty logging is on

   - New VMID allocator, which will eventually help with SVA in VMs

   - Better support for PMUs in heterogenous systems

   - PSCI 1.1 support, enabling support for SYSTEM_RESET2

   - Implement CONFIG_DEBUG_LIST at EL2

   - Make CONFIG_ARM64_ERRATUM_2077057 default y

   - Reduce the overhead of VM exit when no interrupt is pending

   - Remove traces of 32bit ARM host support from the documentation

   - Updated vgic selftests

   - Various cleanups, doc updates and spelling fixes

  RISC-V:
   - Prevent KVM_COMPAT from being selected

   - Optimize __kvm_riscv_switch_to() implementation

   - RISC-V SBI v0.3 support

  s390:
   - memop selftest

   - fix SCK locking

   - adapter interruptions virtualization for secure guests

   - add Claudio Imbrenda as maintainer

   - first step to do proper storage key checking

  x86:
   - Continue switching kvm_x86_ops to static_call(); introduce
     static_call_cond() and __static_call_ret0 when applicable.

   - Cleanup unused arguments in several functions

   - Synthesize AMD 0x80000021 leaf

   - Fixes and optimization for Hyper-V sparse-bank hypercalls

   - Implement Hyper-V's enlightened MSR bitmap for nested SVM

   - Remove MMU auditing

   - Eager splitting of page tables (new aka "TDP" MMU only) when dirty
     page tracking is enabled

   - Cleanup the implementation of the guest PGD cache

   - Preparation for the implementation of Intel IPI virtualization

   - Fix some segment descriptor checks in the emulator

   - Allow AMD AVIC support on systems with physical APIC ID above 255

   - Better API to disable virtualization quirks

   - Fixes and optimizations for the zapping of page tables:

      - Zap roots in two passes, avoiding RCU read-side critical
        sections that last too long for very large guests backed by 4
        KiB SPTEs.

      - Zap invalid and defunct roots asynchronously via
        concurrency-managed work queue.

      - Allowing yielding when zapping TDP MMU roots in response to the
        root's last reference being put.

      - Batch more TLB flushes with an RCU trick. Whoever frees the
        paging structure now holds RCU as a proxy for all vCPUs running
        in the guest, i.e. to prolongs the grace period on their behalf.
        It then kicks the the vCPUs out of guest mode before doing
        rcu_read_unlock().

  Generic:
   - Introduce __vcalloc and use it for very large allocations that need
     memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  KVM: use kvcalloc for array allocations
  KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
  kvm: x86: Require const tsc for RT
  KVM: x86: synthesize CPUID leaf 0x80000021h if useful
  KVM: x86: add support for CPUID leaf 0x80000021
  KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask
  Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
  kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU
  KVM: arm64: fix typos in comments
  KVM: arm64: Generalise VM features into a set of flags
  KVM: s390: selftests: Add error memop tests
  KVM: s390: selftests: Add more copy memop tests
  KVM: s390: selftests: Add named stages for memop test
  KVM: s390: selftests: Add macro as abstraction for MEM_OP
  KVM: s390: selftests: Split memop tests
  KVM: s390x: fix SCK locking
  RISC-V: KVM: Implement SBI HSM suspend call
  RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function
  RISC-V: Add SBI HSM suspend related defines
  RISC-V: KVM: Implement SBI v0.3 SRST extension
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache</title>
<updated>2022-03-23T00:03:12+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-23T00:03:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9030fb0bb9d607908d51f9ee02efdbe01da355ee'/>
<id>9030fb0bb9d607908d51f9ee02efdbe01da355ee</id>
<content type='text'>
Pull folio updates from Matthew Wilcox:

 - Rewrite how munlock works to massively reduce the contention on
   i_mmap_rwsem (Hugh Dickins):

     https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/

 - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph
   Hellwig):

     https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/

 - Convert GUP to use folios and make pincount available for order-1
   pages. (Matthew Wilcox)

 - Convert a few more truncation functions to use folios (Matthew
   Wilcox)

 - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew
   Wilcox)

 - Convert rmap_walk to use folios (Matthew Wilcox)

 - Convert most of shrink_page_list() to use a folio (Matthew Wilcox)

 - Add support for creating large folios in readahead (Matthew Wilcox)

* tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits)
  mm/damon: minor cleanup for damon_pa_young
  selftests/vm/transhuge-stress: Support file-backed PMD folios
  mm/filemap: Support VM_HUGEPAGE for file mappings
  mm/readahead: Switch to page_cache_ra_order
  mm/readahead: Align file mappings for non-DAX
  mm/readahead: Add large folio readahead
  mm: Support arbitrary THP sizes
  mm: Make large folios depend on THP
  mm: Fix READ_ONLY_THP warning
  mm/filemap: Allow large folios to be added to the page cache
  mm: Turn can_split_huge_page() into can_split_folio()
  mm/vmscan: Convert pageout() to take a folio
  mm/vmscan: Turn page_check_references() into folio_check_references()
  mm/vmscan: Account large folios correctly
  mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios
  mm/vmscan: Free non-shmem folios without splitting them
  mm/rmap: Constify the rmap_walk_control argument
  mm/rmap: Convert rmap_walk() to take a folio
  mm: Turn page_anon_vma() into folio_anon_vma()
  mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull folio updates from Matthew Wilcox:

 - Rewrite how munlock works to massively reduce the contention on
   i_mmap_rwsem (Hugh Dickins):

     https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/

 - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph
   Hellwig):

     https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/

 - Convert GUP to use folios and make pincount available for order-1
   pages. (Matthew Wilcox)

 - Convert a few more truncation functions to use folios (Matthew
   Wilcox)

 - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew
   Wilcox)

 - Convert rmap_walk to use folios (Matthew Wilcox)

 - Convert most of shrink_page_list() to use a folio (Matthew Wilcox)

 - Add support for creating large folios in readahead (Matthew Wilcox)

* tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits)
  mm/damon: minor cleanup for damon_pa_young
  selftests/vm/transhuge-stress: Support file-backed PMD folios
  mm/filemap: Support VM_HUGEPAGE for file mappings
  mm/readahead: Switch to page_cache_ra_order
  mm/readahead: Align file mappings for non-DAX
  mm/readahead: Add large folio readahead
  mm: Support arbitrary THP sizes
  mm: Make large folios depend on THP
  mm: Fix READ_ONLY_THP warning
  mm/filemap: Allow large folios to be added to the page cache
  mm: Turn can_split_huge_page() into can_split_folio()
  mm/vmscan: Convert pageout() to take a folio
  mm/vmscan: Turn page_check_references() into folio_check_references()
  mm/vmscan: Account large folios correctly
  mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios
  mm/vmscan: Free non-shmem folios without splitting them
  mm/rmap: Constify the rmap_walk_control argument
  mm/rmap: Convert rmap_walk() to take a folio
  mm: Turn page_anon_vma() into folio_anon_vma()
  mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: Turn page_anon_vma() into folio_anon_vma()</title>
<updated>2022-03-21T17:01:35+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-01-29T16:52:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e05b34539d008ab819388f699b25eae962ba24ac'/>
<id>e05b34539d008ab819388f699b25eae962ba24ac</id>
<content type='text'>
Move the prototype from mm.h to mm/internal.h and convert all callers
to pass a folio.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the prototype from mm.h to mm/internal.h and convert all callers
to pass a folio.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: Add folio_mapcount()</title>
<updated>2022-03-21T16:59:02+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-01-17T21:33:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4ba1119cd53166d853050ff1a9d76079cd8f8e06'/>
<id>4ba1119cd53166d853050ff1a9d76079cd8f8e06</id>
<content type='text'>
This implements the same algorithm as total_mapcount(), which is
transformed into a wrapper function.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This implements the same algorithm as total_mapcount(), which is
transformed into a wrapper function.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
</pre>
</div>
</content>
</entry>
</feed>
