Commit Graph

342 Commits

Author SHA1 Message Date
Mike Rapoport (Microsoft)
1b5695b024 mm: make range-to-target_node lookup facility a part of numa_memblks
The x86 implementation of range-to-target_node lookup (i.e. 
phys_to_target_node() and memory_add_physaddr_to_nid()) relies on
numa_memblks.

Since numa_memblks are now part of the generic code, move these functions
from x86 to mm/numa_memblks.c and select CONFIG_NUMA_KEEP_MEMINFO when
CONFIG_NUMA_MEMBLKS=y for dax and cxl.

[rppt@kernel.org: fix build]
  Link: https://lkml.kernel.org/r/ZtVfSt_zloPdDqVB@kernel.org
Link: https://lkml.kernel.org/r/20240807064110.1003856-26-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU]
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Arnd Bergmann <arnd@arndb.de>
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: Davidlohr Bueso <dave@stgolabs.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Rob Herring (Arm) <robh@kernel.org>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-03 21:15:32 -07:00
Peter Xu
5b198b4759 mm/dax: dump start address in fault handler
Patch series "mm/mprotect: Fix dax puds", v5.

Dax supports pud pages for a while, but mprotect on puds was missing since
the start.  This series tries to fix that by providing pud handling in
mprotect().  The goal is to add more types of pud mappings like hugetlb or
pfnmaps.  This series paves way for it by fixing known pud entries.

Considering nobody reported this until when I looked at those other types
of pud mappings, I am thinking maybe it doesn't need to be a fix for
stable and this may not need to be backported.  I would guess whoever
cares about mprotect() won't care 1G dax puds yet, vice versa.  I hope
fixing that in new kernels would be fine, but I'm open to suggestions.

There're a few small things changed to teach mprotect work on PUDs.  E.g. 
it will need to start with dropping NUMA_HUGE_PTE_UPDATES which may stop
making sense when there can be more than one type of huge pte.  OTOH,
we'll also need to push the mmu notifiers from pmd to pud layers, which
might need some attention but so far I think it's safe.  For such details,
please refer to each patch's commit message.

The mprotect() pud process should be straightforward, as I kept it as
simple as possible.  There's no NUMA handled as dax simply doesn't support
that.  There's also no userfault involvements as file memory (even if work
with userfault-wp async mode) will need to split a pud, so pud entry
doesn't need to yet know userfault's existance (but hugetlb entries will;
that's also for later).


This patch (of 7):

Currently the dax fault handler dumps the vma range when dynamic debugging
enabled.  That's mostly not useful.  Dump the (aligned) address instead
with the order info.

Link: https://lkml.kernel.org/r/20240812181225.1360970-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20240812181225.1360970-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:26:08 -07:00
Linus Torvalds
c2a96b7f18 Driver core changes for 6.11-rc1
Here is the big set of driver core changes for 6.11-rc1.
 
 Lots of stuff in here, with not a huge diffstat, but apis are evolving
 which required lots of files to be touched.  Highlights of the changes
 in here are:
   - platform remove callback api final fixups (Uwe took many releases to
     get here, finally!)
   - Rust bindings for basic firmware apis and initial driver-core
     interactions.  It's not all that useful for a "write a whole driver
     in rust" type of thing, but the firmware bindings do help out the
     phy rust drivers, and the driver core bindings give a solid base on
     which others can start their work.  There is still a long way to go
     here before we have a multitude of rust drivers being added, but
     it's a great first step.
   - driver core const api changes.  This reached across all bus types,
     and there are some fix-ups for some not-common bus types that
     linux-next and 0-day testing shook out.  This work is being done to
     help make the rust bindings more safe, as well as the C code, moving
     toward the end-goal of allowing us to put driver structures into
     read-only memory.  We aren't there yet, but are getting closer.
   - minor devres cleanups and fixes found by code inspection
   - arch_topology minor changes
   - other minor driver core cleanups
 
 All of these have been in linux-next for a very long time with no
 reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZqH+aQ8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ymoOQCfVBdLcBjEDAGh3L8qHRGMPy4rV2EAoL/r+zKm
 cJEYtJpGtWX6aAtugm9E
 =ZyJV
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 6.11-rc1.

  Lots of stuff in here, with not a huge diffstat, but apis are evolving
  which required lots of files to be touched. Highlights of the changes
  in here are:

   - platform remove callback api final fixups (Uwe took many releases
     to get here, finally!)

   - Rust bindings for basic firmware apis and initial driver-core
     interactions.

     It's not all that useful for a "write a whole driver in rust" type
     of thing, but the firmware bindings do help out the phy rust
     drivers, and the driver core bindings give a solid base on which
     others can start their work.

     There is still a long way to go here before we have a multitude of
     rust drivers being added, but it's a great first step.

   - driver core const api changes.

     This reached across all bus types, and there are some fix-ups for
     some not-common bus types that linux-next and 0-day testing shook
     out.

     This work is being done to help make the rust bindings more safe,
     as well as the C code, moving toward the end-goal of allowing us to
     put driver structures into read-only memory. We aren't there yet,
     but are getting closer.

   - minor devres cleanups and fixes found by code inspection

   - arch_topology minor changes

   - other minor driver core cleanups

  All of these have been in linux-next for a very long time with no
  reported problems"

* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  ARM: sa1100: make match function take a const pointer
  sysfs/cpu: Make crash_hotplug attribute world-readable
  dio: Have dio_bus_match() callback take a const *
  zorro: make match function take a const pointer
  driver core: module: make module_[add|remove]_driver take a const *
  driver core: make driver_find_device() take a const *
  driver core: make driver_[create|remove]_file take a const *
  firmware_loader: fix soundness issue in `request_internal`
  firmware_loader: annotate doctests as `no_run`
  devres: Correct code style for functions that return a pointer type
  devres: Initialize an uninitialized struct member
  devres: Fix memory leakage caused by driver API devm_free_percpu()
  devres: Fix devm_krealloc() wasting memory
  driver core: platform: Switch to use kmemdup_array()
  driver core: have match() callback in struct bus_type take a const *
  MAINTAINERS: add Rust device abstractions to DRIVER CORE
  device: rust: improve safety comments
  MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
  MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
  firmware: rust: improve safety comments
  ...
2024-07-25 10:42:22 -07:00
Greg Kroah-Hartman
d69d804845 driver core: have match() callback in struct bus_type take a const *
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-03 15:16:54 +02:00
Jeff Johnson
1d5198dd08 dax: add missing MODULE_DESCRIPTION() macros
make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/hmem/dax_hmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/device_dax.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/kmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/dax_pmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/dax_cxl.o

Add all missing invocations of the MODULE_DESCRIPTION() macro.

[iweiny: edit descriptions]

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://patch.msgid.link/r/20240605-md-drivers-dax-v1-1-3d448f3368b4@quicinc.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-06-17 18:42:16 -05:00
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".
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZkgQYwAKCRDdBJ7gKXxA
 jrdKAP9WVJdpEcXxpoub/vVE0UWGtffr8foifi9bCwrQrGh5mgEAx7Yf0+d/oBZB
 nvA4E0DcPrUAFy144FNM0NTCb7u9vAw=
 =V3R/
 -----END PGP SIGNATURE-----

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
  ...
2024-05-19 09:21:03 -07:00
Linus Torvalds
c405aa3ea3 Updates for nvdimm for 6.10
Code cleanups, remove duplicate code, and updates for current
 interfaces.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYKADIWIQSgX9xt+GwmrJEQ+euebuN7TNx1MQUCZkThOhQcaXJhLndlaW55
 QGludGVsLmNvbQAKCRCebuN7TNx1MWUvAP9VuWLTc+bCguRMbArOsdE2T60780pR
 DT12KXfwm/FvKAD9Hyz8S2CkwvdlwC5hqH2AmdpzDhpJ1f9LBpcsb6GUKwk=
 =eZC/
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull nvdimm updates from Ira Weiny:
 "The changes include removing duplicate code and updating the nvdimm
  tree to the current kernel interfaces such as using const for struct
  device_type and changing the platform remove callback signature"

* tag 'libnvdimm-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: remove redundant assignment to variable rc
  ndtest: Convert to platform remove callback returning void
  nvdimm/btt: always set max_integrity_segments
  nvdimm: remove nd_integrity_init
  dax: constify the struct device_type usage
  powerpc/papr_scm: Move duplicate definitions to common header files
2024-05-15 14:28:56 -07:00
Vishal Verma
2acf04532d dax/bus.c: use the right locking mode (read vs write) in size_show
In size_show(), the dax_dev_rwsem only needs a read lock, but was
acquiring a write lock.  Change it to down_read_interruptible() so it
doesn't unnecessarily hold a write lock.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-4-e3dcd755774c@intel.com
Fixes: c05ae9d85b ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-07 10:37:01 -07:00
Vishal Verma
e39dbcfba7 dax/bus.c: don't use down_write_killable for non-user processes
Change an instance of down_write_killable() to a simple down_write() where
there is no user process that might want to interrupt the operation.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-3-e3dcd755774c@intel.com
Fixes: c05ae9d85b ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-07 10:37:01 -07:00
Vishal Verma
6f6544f27e dax/bus.c: fix locking for unregister_dax_dev / unregister_dax_mapping paths
Commit c05ae9d85b ("dax/bus.c: replace driver-core lock usage by a local
rwsem") aimed to undo device_lock() abuses for protecting changes to
dax-driver internal data-structures like the dax_region resource tree to
device-dax-instance range structures.  However, the device_lock() was
legitimately enforcing that devices to be deleted were not current
actively attached to any driver nor assigned any capacity from the region.

As a result of the device_lock restoration in delete_store(), the
conditional locking in unregister_dev_dax() and unregister_dax_mapping()
can be removed.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-2-e3dcd755774c@intel.com
Fixes: c05ae9d85b ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-07 10:37:00 -07:00
Vishal Verma
c14c647bbe dax/bus.c: replace WARN_ON_ONCE() with lockdep asserts
Patch series "dax/bus.c: Fixups for dax-bus locking", v3.

Commit Fixes: c05ae9d85b ("dax/bus.c: replace driver-core lock usage by
a local rwsem") introduced a few problems that this series aims to fix. 
Add back device_lock() where it was correctly used (during device
manipulation operations), remove conditional locking in
unregister_dax_dev() and unregister_dax_mapping(), use non-interruptible
versions of rwsem locks when not called from a user process, and fix up a
write vs.  read usage of an rwsem.


This patch (of 4):

In [1], Dan points out that all of the WARN_ON_ONCE() usage in the
referenced patch should be replaced with lockdep_assert_held, or
lockdep_held_assert_write().  Replace these as appropriate.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-0-e3dcd755774c@intel.com
Link: https://lore.kernel.org/r/65f0b5ef41817_aa222941a@dwillia2-mobl3.amr.corp.intel.com.notmuch [1]
Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-1-e3dcd755774c@intel.com
Fixes: c05ae9d85b ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-07 10:37:00 -07:00
Ho-Ren (Jack) Chuang
a72a30af55 memory tier: dax/kmem: introduce an abstract layer for finding, allocating, and putting memory types
Patch series "Improved Memory Tier Creation for CPUless NUMA Nodes", v11.

When a memory device, such as CXL1.1 type3 memory, is emulated as normal
memory (E820_TYPE_RAM), the memory device is indistinguishable from normal
DRAM in terms of memory tiering with the current implementation.  The
current memory tiering assigns all detected normal memory nodes to the
same DRAM tier.  This results in normal memory devices with different
attributions being unable to be assigned to the correct memory tier,
leading to the inability to migrate pages between different types of
memory. 
https://lore.kernel.org/linux-mm/PH0PR08MB7955E9F08CCB64F23963B5C3A860A@PH0PR08MB7955.namprd08.prod.outlook.com/T/

This patchset automatically resolves the issues.  It delays the
initialization of memory tiers for CPUless NUMA nodes until they obtain
HMAT information and after all devices are initialized at boot time,
eliminating the need for user intervention.  If no HMAT is specified, it
falls back to using `default_dram_type`.

Example usecase:
We have CXL memory on the host, and we create VMs with a new system memory
device backed by host CXL memory.  We inject CXL memory performance
attributes through QEMU, and the guest now sees memory nodes with
performance attributes in HMAT.  With this change, we enable the guest
kernel to construct the correct memory tiering for the memory nodes.


This patch (of 2):

Since different memory devices require finding, allocating, and putting
memory types, these common steps are abstracted in this patch, enhancing
the scalability and conciseness of the code.

Link: https://lkml.kernel.org/r/20240405000707.2670063-1-horenchuang@bytedance.com
Link: https://lkml.kernel.org/r/20240405000707.2670063-2-horenchuang@bytedance.com
Signed-off-by: Ho-Ren (Jack) Chuang <horenchuang@bytedance.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawie.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Gregory Price <gourry.memverge@gmail.com>
Cc: Hao Xiang <hao.xiang@bytedance.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ravi Jonnalagadda <ravis.opensrc@micron.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:25 -07:00
Rick Edgecombe
529ce23a76 mm: switch mm->get_unmapped_area() to a flag
The mm_struct contains a function pointer *get_unmapped_area(), which is
set to either arch_get_unmapped_area() or arch_get_unmapped_area_topdown()
during the initialization of the mm.

Since the function pointer only ever points to two functions that are
named the same across all arch's, a function pointer is not really
required.  In addition future changes will want to add versions of the
functions that take additional arguments.  So to save a pointers worth of
bytes in mm_struct, and prevent adding additional function pointers to
mm_struct in future changes, remove it and keep the information about
which get_unmapped_area() to use in a flag.

Add the new flag to MMF_INIT_MASK so it doesn't get clobbered on fork by
mmf_init_flags().  Most MM flags get clobbered on fork.  In the
pre-existing behavior mm->get_unmapped_area() would get copied to the new
mm in dup_mm(), so not clobbering the flag preserves the existing behavior
around inheriting the topdown-ness.

Introduce a helper, mm_get_unmapped_area(), to easily convert code that
refers to the old function pointer to instead select and call either
arch_get_unmapped_area() or arch_get_unmapped_area_topdown() based on the
flag.  Then drop the mm->get_unmapped_area() function pointer.  Leave the
get_unmapped_area() pointer in struct file_operations alone.  The main
purpose of this change is to reorganize in preparation for future changes,
but it also converts the calls of mm->get_unmapped_area() from indirect
branches into a direct ones.

The stress-ng bigheap benchmark calls realloc a lot, which calls through
get_unmapped_area() in the kernel.  On x86, the change yielded a ~1%
improvement there on a retpoline config.

In testing a few x86 configs, removing the pointer unfortunately didn't
result in any actual size reductions in the compiled layout of mm_struct. 
But depending on compiler or arch alignment requirements, the change could
shrink the size of mm_struct.

Link: https://lkml.kernel.org/r/20240326021656.202649-3-rick.p.edgecombe@intel.com
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:56:25 -07:00
Colin Ian King
41147b006b dax: remove redundant assignment to variable rc
The variable rc is being assigned an value and then is being re-assigned
a new value in the next statement. The assignment is redundant and can
be removed.

Cleans up clang scan build warning:
drivers/dax/bus.c:1207:2: warning: Value stored to 'rc' is never
read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/20240415101928.484143-1-colin.i.king@gmail.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-04-25 14:11:11 -07:00
Ricardo B. Marliere
2c720b492c dax: constify the struct device_type usage
Since commit aed65af1cc ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the
dax_mapping_type variable to be a constant structure as well, placing it
into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20240219-device_cleanup-dax-v1-1-6b319ee89dc2@marliere.net
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-04-25 12:37:12 -07:00
Christian Brauner
210a03c9d5
fs: claw back a few FMODE_* bits
There's a bunch of flags that are purely based on what the file
operations support while also never being conditionally set or unset.
IOW, they're not subject to change for individual files. Imho, such
flags don't need to live in f_mode they might as well live in the fops
structs itself. And the fops struct already has that lonely
mmap_supported_flags member. We might as well turn that into a generic
fop_flags member and move a few flags from FMODE_* space into FOP_*
space. That gets us four FMODE_* bits back and the ability for new
static flags that are about file ops to not have to live in FMODE_*
space but in their own FOP_* space. It's not the most beautiful thing
ever but it gets the job done. Yes, there'll be an additional pointer
chase but hopefully that won't matter for these flags.

I suspect there's a few more we can move into there and that we can also
redirect a bunch of new flag suggestions that follow this pattern into
the fop_flags field instead of f_mode.

Link: https://lore.kernel.org/r/20240328-gewendet-spargel-aa60a030ef74@brauner
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-07 13:49:02 +02:00
Linus Torvalds
4757c3c64a libnvdimm updates for v6.9
- ACPI_NFIT Kconfig documetation fix
 - Make nvdimm_bus_type const
 - Make dax_bus_type const
 - remove SLAB_MEM_SPREAD flag usage in DAX
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE5DAy15EJMCV1R6v9YGjFFmlTOEoFAmXzXRkACgkQYGjFFmlT
 OErtJxAA1/83IIfJ/3gaqzHe/NPqiuTPpcOtHrCKZ3ug2DrCeKNKfHAB9ODCnGX8
 LHDKacRLBexJSyXYRzfRxNQNg9RqhC2bpuCzDTk6ulxHYBP6aEZScnQ4RSm8K2Zo
 dOJ9VvzO1MlWYLwhLnqbz5apkOvj1dSdlsdbMQBMD7ZlvK2AReNVCqIlPUjPH4HG
 Z/Mw6v7Z1qGVQNr5Nt4/lHkSrNaSBUmMaI6gEZn0PGwFPqmU5qYOZtBM8zPtUbFF
 g9IBs69EVqh3cfTMrHqFJebEaqiVOBrGZk5bQ6CgrAVHyjpoPQSQHLclqaYIi6bD
 pyF1o4EKUF94OB7AKIVg6JxF5jAscMg7Xo7tlcv2KZCcqFxt+DOAJX/uGMhjSyfv
 FB20bI3lN+d2Hmrg3Q6IMGYi4KWyIhSaJOAFDJA5rUYqR7dyzLMqbp/sZo7j43Z3
 YQrJxfV92TMGS/nVJUL1Kvb+dgc2+ZSycZiQP1MHuxPqMKL2WgSkz0shPx0iJ5o+
 wKuOEjOlGffZrdRy1z6F1Px62JelLe7sMTtMKN5Ft3P1eG6wV52eEV/ripV/+whP
 VrmlA2QfKE4XioVRJn+3GFJicObPA+P/qfpYK8Hf0Nfd9p6MR8YqfRfy5Y8qDU78
 g/2uBxp45VXs1bN86ZWnjJZdQqmmA6Zlyda6N3+DC8OLtvgnU2g=
 =Ztme
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dave Jiang:

 - ACPI_NFIT Kconfig documetation fix

 - Make nvdimm_bus_type const

 - Make dax_bus_type const

 - remove SLAB_MEM_SPREAD flag usage in DAX

* tag 'libnvdimm-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: remove SLAB_MEM_SPREAD flag usage
  device-dax: make dax_bus_type const
  nvdimm: make nvdimm_bus_type const
  libnvdimm: Fix ACPI_NFIT in BLK_DEV_PMEM help
2024-03-15 11:58:32 -07:00
Linus Torvalds
902861e34c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
from hotplugged memory rather than only from main memory.  Series
   "implement "memmap on memory" feature on s390".
 
 - More folio conversions from Matthew Wilcox in the series
 
 	"Convert memcontrol charge moving to use folios"
 	"mm: convert mm counter to take a folio"
 
 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes.  The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".
 
 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.
 
 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools".  Measured improvements are modest.
 
 - zswap cleanups and simplifications from Yosry Ahmed in the series "mm:
   zswap: simplify zswap_swapoff()".
 
 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is hotplugged
   as system memory.
 
 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.
 
 - More DAMON work from SeongJae Park in the series
 
 	"mm/damon: make DAMON debugfs interface deprecation unignorable"
 	"selftests/damon: add more tests for core functionalities and corner cases"
 	"Docs/mm/damon: misc readability improvements"
 	"mm/damon: let DAMOS feeds and tame/auto-tune itself"
 
 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving policy
   wherein we allocate memory across nodes in a weighted fashion rather
   than uniformly.  This is beneficial in heterogeneous memory environments
   appearing with CXL.
 
 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".
 
 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".
 
 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format.  Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.
 
 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP".  Mainly
   targeted at arm64, this significantly speeds up fork() when the process
   has a large number of pte-mapped folios.
 
 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP".  It
   implements batching during munmap() and other pte teardown situations.
   The microbenchmark improvements are nice.
 
 - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan
   Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings").  Kernel build times on arm64 improved nicely.  Ryan's series
   "Address some contpte nits" provides some followup work.
 
 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page faults.
   He has also added a reproducer under the selftest code.
 
 - In the series "selftests/mm: Output cleanups for the compaction test",
   Mark Brown did what the title claims.
 
 - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring".
 
 - Even more zswap material from Nhat Pham.  The series "fix and extend
   zswap kselftests" does as claimed.
 
 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in
   our handling of DAX on archiecctures which have virtually aliasing data
   caches.  The arm architecture is the main beneficiary.
 
 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic
   improvements in worst-case mmap_lock hold times during certain
   userfaultfd operations.
 
 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series
 
 	"page_owner: print stacks and their outstanding allocations"
 	"page_owner: Fixup and cleanup"
 
 - Uladzislau Rezki has contributed some vmalloc scalability improvements
   in his series "Mitigate a vmap lock contention".  It realizes a 12x
   improvement for a certain microbenchmark.
 
 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".
 
 - Some zsmalloc maintenance work from Chengming Zhou in the series
 
 	"mm/zsmalloc: fix and optimize objects/page migration"
 	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"
 
 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0.  This a step along the path to implementaton of the merging of
   large anonymous folios.  The series is named "Enable >0 order folio
   memory compaction".
 
 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages() to
   an iterator".
 
 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".
 
 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios.  The
   series is named "Split a folio to any lower order folios".
 
 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.
 
 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".
 
 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which are
   configured to use large numbers of hugetlb pages.
 
 - Matthew Wilcox's series "PageFlags cleanups" does that.
 
 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also.  S390 is affected.
 
 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".
 
 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM Selftests".
 
 - Also, of course, many singleton patches to many things.  Please see
   the individual changelogs for details.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZfJpPQAKCRDdBJ7gKXxA
 joxeAP9TrcMEuHnLmBlhIXkWbIR4+ki+pA3v+gNTlJiBhnfVSgD9G55t1aBaRplx
 TMNhHfyiHYDTx/GAV9NXW84tasJSDgA=
 =TG55
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
   from hotplugged memory rather than only from main memory. Series
   "implement "memmap on memory" feature on s390".

 - More folio conversions from Matthew Wilcox in the series

	"Convert memcontrol charge moving to use folios"
	"mm: convert mm counter to take a folio"

 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes. The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".

 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.

 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools". Measured improvements are modest.

 - zswap cleanups and simplifications from Yosry Ahmed in the series
   "mm: zswap: simplify zswap_swapoff()".

 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is
   hotplugged as system memory.

 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.

 - More DAMON work from SeongJae Park in the series

	"mm/damon: make DAMON debugfs interface deprecation unignorable"
	"selftests/damon: add more tests for core functionalities and corner cases"
	"Docs/mm/damon: misc readability improvements"
	"mm/damon: let DAMOS feeds and tame/auto-tune itself"

 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving
   policy wherein we allocate memory across nodes in a weighted fashion
   rather than uniformly. This is beneficial in heterogeneous memory
   environments appearing with CXL.

 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".

 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".

 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format. Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.

 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
   targeted at arm64, this significantly speeds up fork() when the
   process has a large number of pte-mapped folios.

 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
   implements batching during munmap() and other pte teardown
   situations. The microbenchmark improvements are nice.

 - And in the series "Transparent Contiguous PTEs for User Mappings"
   Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings"). Kernel build times on arm64 improved nicely. Ryan's
   series "Address some contpte nits" provides some followup work.

 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page
   faults. He has also added a reproducer under the selftest code.

 - In the series "selftests/mm: Output cleanups for the compaction
   test", Mark Brown did what the title claims.

 - Kinsey Ho has added the series "mm/mglru: code cleanup and
   refactoring".

 - Even more zswap material from Nhat Pham. The series "fix and extend
   zswap kselftests" does as claimed.

 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
   in our handling of DAX on archiecctures which have virtually aliasing
   data caches. The arm architecture is the main beneficiary.

 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides
   dramatic improvements in worst-case mmap_lock hold times during
   certain userfaultfd operations.

 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series

	"page_owner: print stacks and their outstanding allocations"
	"page_owner: Fixup and cleanup"

 - Uladzislau Rezki has contributed some vmalloc scalability
   improvements in his series "Mitigate a vmap lock contention". It
   realizes a 12x improvement for a certain microbenchmark.

 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".

 - Some zsmalloc maintenance work from Chengming Zhou in the series

	"mm/zsmalloc: fix and optimize objects/page migration"
	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"

 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0. This a step along the path to implementaton of the merging
   of large anonymous folios. The series is named "Enable >0 order folio
   memory compaction".

 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages()
   to an iterator".

 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".

 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios. The
   series is named "Split a folio to any lower order folios".

 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.

 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".

 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which
   are configured to use large numbers of hugetlb pages.

 - Matthew Wilcox's series "PageFlags cleanups" does that.

 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also. S390 is affected.

 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".

 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM
   Selftests".

 - Also, of course, many singleton patches to many things. Please see
   the individual changelogs for details.

* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
  mm/zswap: remove the memcpy if acomp is not sleepable
  crypto: introduce: acomp_is_async to expose if comp drivers might sleep
  memtest: use {READ,WRITE}_ONCE in memory scanning
  mm: prohibit the last subpage from reusing the entire large folio
  mm: recover pud_leaf() definitions in nopmd case
  selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
  selftests/mm: skip uffd hugetlb tests with insufficient hugepages
  selftests/mm: dont fail testsuite due to a lack of hugepages
  mm/huge_memory: skip invalid debugfs new_order input for folio split
  mm/huge_memory: check new folio order when split a folio
  mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
  mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
  mm: fix list corruption in put_pages_list
  mm: remove folio from deferred split list before uncharging it
  filemap: avoid unnecessary major faults in filemap_fault()
  mm,page_owner: drop unnecessary check
  mm,page_owner: check for null stack_record before bumping its refcount
  mm: swap: fix race between free_swap_and_cache() and swapoff()
  mm/treewide: align up pXd_leaf() retval across archs
  mm/treewide: drop pXd_large()
  ...
2024-03-14 17:43:30 -07:00
Linus Torvalds
f88c3fb81c mm, slab: remove last vestiges of SLAB_MEM_SPREAD
Yes, yes, I know the slab people were planning on going slow and letting
every subsystem fight this thing on their own.  But let's just rip off
the band-aid and get it over and done with.  I don't want to see a
number of unnecessary pull requests just to get rid of a flag that no
longer has any meaning.

This was mainly done with a couple of 'sed' scripts and then some manual
cleanup of the end result.

Link: https://lore.kernel.org/all/CAHk-=wji0u+OOtmAOD-5JV3SXcRJF___k_+8XNKmak0yd5vW1Q@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-03-12 20:32:19 -07:00
Chengming Zhou
d9212b35da dax: remove SLAB_MEM_SPREAD flag usage
The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
removed as of v6.8-rc1, so it became a dead flag since the commit
16a1d96835 ("mm/slab: remove mm/slab.c and slab_def.h"). And the
series[1] went on to mark it obsolete explicitly to avoid confusion
for users. Here we can just remove all its users, which has no any
functional change.

[1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/20240224134728.829289-1-chengming.zhou@linux.dev
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-03-04 09:10:37 -07:00
Mathieu Desnoyers
902ccb86ed dax: fix incorrect list of data cache aliasing architectures
commit d92576f116 ("dax: does not work correctly with virtual aliasing caches")
prevents DAX from building on architectures with virtually aliased
dcache with:

  depends on !(ARM || MIPS || SPARC)

This check is too broad (e.g. recent ARMv7 don't have virtually aliased
dcaches), and also misses many other architectures with virtually
aliased data cache.

This is a regression introduced in the v4.0 Linux kernel where the
dax mount option is removed for 32-bit ARMv7 boards which have no data
cache aliasing, and therefore should work fine with FS_DAX.

This was turned into the following check in alloc_dax() by a preparatory
change:

        if (ops && (IS_ENABLED(CONFIG_ARM) ||
            IS_ENABLED(CONFIG_MIPS) ||
            IS_ENABLED(CONFIG_SPARC)))
                return NULL;

Use cpu_dcache_is_aliasing() instead to figure out whether the environment
has aliasing data caches.

Link: https://lkml.kernel.org/r/20240215144633.96437-10-mathieu.desnoyers@efficios.com
Fixes: d92576f116 ("dax: does not work correctly with virtual aliasing caches")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Sclafani <dm-devel@lists.linux.dev>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:27:20 -08:00
Mathieu Desnoyers
1df4ca0155 dax: check for data cache aliasing at runtime
Replace the following fs/Kconfig:FS_DAX dependency:

  depends on !(ARM || MIPS || SPARC)

By a runtime check within alloc_dax(). This runtime check returns
ERR_PTR(-EOPNOTSUPP) if the @ops parameter is non-NULL (which means
the kernel is using an aliased mapping) on an architecture which
has data cache aliasing.

Change the return value from NULL to PTR_ERR(-EOPNOTSUPP) for
CONFIG_DAX=n for consistency.

This is done in preparation for using cpu_dcache_is_aliasing() in a
following change which will properly support architectures which detect
data cache aliasing at runtime.

Link: https://lkml.kernel.org/r/20240215144633.96437-8-mathieu.desnoyers@efficios.com
Fixes: d92576f116 ("dax: does not work correctly with virtual aliasing caches")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Sclafani <dm-devel@lists.linux.dev>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:27:19 -08:00
Mathieu Desnoyers
6d439c18d9 dax: alloc_dax() return ERR_PTR(-EOPNOTSUPP) for CONFIG_DAX=n
Change the return value from NULL to PTR_ERR(-EOPNOTSUPP) for
CONFIG_DAX=n to be consistent with the fact that CONFIG_DAX=y
never returns NULL.

This is done in preparation for using cpu_dcache_is_aliasing() in a
following change which will properly support architectures which detect
data cache aliasing at runtime.

Link: https://lkml.kernel.org/r/20240215144633.96437-3-mathieu.desnoyers@efficios.com
Fixes: 4e4ced9379 ("dax: Move mandatory ->zero_page_range() check in alloc_dax()")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Sclafani <dm-devel@lists.linux.dev>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:27:19 -08:00
Vishal Verma
73954d379e dax: add a sysfs knob to control memmap_on_memory behavior
Add a sysfs knob for dax devices to control the memmap_on_memory setting
if the dax device were to be hotplugged as system memory.

The default memmap_on_memory setting for dax devices originating via pmem
or hmem is set to 'false' - i.e.  no memmap_on_memory semantics, to
preserve legacy behavior.  For dax devices via CXL, the default is on. 
The sysfs control allows the administrator to override the above defaults
if needed.

Link: https://lkml.kernel.org/r/20240124-vv-dax_abi-v7-5-20d16cb8d23d@intel.com
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Tested-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Huang, Ying <ying.huang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 10:24:40 -08:00
Vishal Verma
6ebed0007f dax/bus.c: replace several sprintf() with sysfs_emit()
There were several places where drivers/dax/bus.c uses 'sprintf' to print
sysfs data.  Since a sysfs_emit() helper is available specifically for
this purpose, replace all the sprintf() usage for sysfs with sysfs_emit()
in this file.

Link: https://lkml.kernel.org/r/20240124-vv-dax_abi-v7-2-20d16cb8d23d@intel.com
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Li Zhijian <lizhijian@fujitsu.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 10:24:40 -08:00
Vishal Verma
c05ae9d85b dax/bus.c: replace driver-core lock usage by a local rwsem
Patch series "Add DAX ABI for memmap_on_memory", v7.

This series adds sysfs ABI to control memmap_on_memory behavior for DAX
devices.

Patch 1 replaces incorrect device_lock() usage with a local rwsem - this
was identified during review.

Patch 2 is also a preparatory patch that replaces sprintf() for sysfs
operations with sysfs_emit()

Patch 3 adds the missing documentation for the sysfs ABI for DAX regions
and Dax devices.

Patch 4 exports mhp_supports_memmap_on_memory().

Patch 5 adds the new ABI for toggling memmap_on_memory semantics for dax
devices.


This patch (of 5):

The dax driver incorrectly used driver-core device locks to protect
internal dax region and dax device configuration structures.  Replace the
device lock usage with a local rwsem, one each for dax region
configuration and dax device configuration.  As a result of this
conversion, no device_lock() usage remains in dax/bus.c.

Link: https://lkml.kernel.org/r/20240124-vv-dax_abi-v7-0-20d16cb8d23d@intel.com
Link: https://lkml.kernel.org/r/20240124-vv-dax_abi-v7-1-20d16cb8d23d@intel.com
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Li Zhijian <lizhijian@fujitsu.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 10:24:40 -08:00
Ricardo B. Marliere
bc22374c96 device-dax: make dax_bus_type const
Now that the driver core can properly handle constant struct bus_type,
move the dax_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240204-bus_cleanup-dax-v1-1-69a6e4a8553b@marliere.net
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-02-12 15:10:21 -07:00
Linus Torvalds
12958e9c4c New code for 6.8:
* New features/functionality
     * Online repair
       * Reserve disk space for online repairs.
       * Fix misinteraction between the AIL and btree bulkloader because of
         which the bulk load fails to queue a buffer for writeback if it
         happens to be on the AIL list.
       * Prevent transaction reservation overflows when reaping blocks during
         online repair.
       * Whenever possible, bulkloader now copies multiple records into a
         block.
       * Support repairing of
         1. Per-AG free space, inode and refcount btrees.
 	2. Ondisk inodes.
 	3. File data and attribute fork mappings.
       * Verify the contents of
         1. Inode and data fork of realtime bitmap file.
 	2. Quota files.
     * Introduce MF_MEM_PRE_REMOVE. This will be used to notify tasks about
       a pmem device being removed.
 
   * Bug fixes
     * Fix memory leak of recovered attri intent items.
     * Fix UAF during log intent recovery.
     * Fix realtime geometry integer overflows.
     * Prevent scrub from live locking in xchk_iget.
     * Prevent fs shutdown when removing files during low free disk space.
     * Prevent transaction reservation overflow when extending an RT device.
     * Prevent incorrect warning from being printed when extending a
       filesystem.
     * Fix an off-by-one error in xreap_agextent_binval.
     * Serialize access to perag radix tree during deletion operation.
     * Fix perag memory leak during growfs.
     * Allow allocation of minlen realtime extent when the maximum sized
       realtime free extent is minlen in size.
 
   * Cleanups
     * Remove duplicate boilerplate code spread across functionality associated
       with different log items.
     * Cleanup resblks interfaces.
     * Pass defer ops pointer to defer helpers instead of an enum.
     * Initialize di_crc in xfs_log_dinode to prevent KMSAN warnings.
     * Use static_assert() instead of BUILD_BUG_ON_MSG() to validate size of
       structures and structure member offsets. This is done in order to be
       able to share the code with userspace.
     * Move XFS documentation under a new directory specific to XFS.
     * Do not invoke deferred ops' ->create_done callback if the deferred
       operation does not have an intent item associated with it.
     * Remove duplicate inclusion of header files from scrub/health.c.
     * Refactor Realtime code.
     * Cleanup attr code.
 
 Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQjMC4mbgVeU7MxEIYH7y4RirJu9AUCZZJQbwAKCRAH7y4RirJu
 9JjkAP9Zg0QZNmAMsZwvgEBbuF/OnHKl4GmPA5uq0jPmSWCOqAEA0HjlOmuNfQWn
 93fIw6CPbt+9QCluTYBwUisKLIJ/wgA=
 =qmO0
 -----END PGP SIGNATURE-----

Merge tag 'xfs-6.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Chandan Babu:
 "New features/functionality:
   - Online repair:
       - Reserve disk space for online repairs
       - Fix misinteraction between the AIL and btree bulkloader because
         of which the bulk load fails to queue a buffer for writeback if
         it happens to be on the AIL list
       - Prevent transaction reservation overflows when reaping blocks
         during online repair
       - Whenever possible, bulkloader now copies multiple records into
         a block
       - Support repairing of
           1. Per-AG free space, inode and refcount btrees
           2. Ondisk inodes
           3. File data and attribute fork mappings
       - Verify the contents of
           1. Inode and data fork of realtime bitmap file
           2. Quota files
   - Introduce MF_MEM_PRE_REMOVE. This will be used to notify tasks
     about a pmem device being removed

  Bug fixes:
   - Fix memory leak of recovered attri intent items
   - Fix UAF during log intent recovery
   - Fix realtime geometry integer overflows
   - Prevent scrub from live locking in xchk_iget
   - Prevent fs shutdown when removing files during low free disk space
   - Prevent transaction reservation overflow when extending an RT
     device
   - Prevent incorrect warning from being printed when extending a
     filesystem
   - Fix an off-by-one error in xreap_agextent_binval
   - Serialize access to perag radix tree during deletion operation
   - Fix perag memory leak during growfs
   - Allow allocation of minlen realtime extent when the maximum sized
     realtime free extent is minlen in size

  Cleanups:
   - Remove duplicate boilerplate code spread across functionality
     associated with different log items
   - Cleanup resblks interfaces
   - Pass defer ops pointer to defer helpers instead of an enum
   - Initialize di_crc in xfs_log_dinode to prevent KMSAN warnings
   - Use static_assert() instead of BUILD_BUG_ON_MSG() to validate size
     of structures and structure member offsets. This is done in order
     to be able to share the code with userspace
   - Move XFS documentation under a new directory specific to XFS
   - Do not invoke deferred ops' ->create_done callback if the deferred
     operation does not have an intent item associated with it
   - Remove duplicate inclusion of header files from scrub/health.c
   - Refactor Realtime code
   - Cleanup attr code"

* tag 'xfs-6.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (123 commits)
  xfs: use the op name in trace_xlog_intent_recovery_failed
  xfs: fix a use after free in xfs_defer_finish_recovery
  xfs: turn the XFS_DA_OP_REPLACE checks in xfs_attr_shortform_addname into asserts
  xfs: remove xfs_attr_sf_hdr_t
  xfs: remove struct xfs_attr_shortform
  xfs: use xfs_attr_sf_findname in xfs_attr_shortform_getvalue
  xfs: remove xfs_attr_shortform_lookup
  xfs: simplify xfs_attr_sf_findname
  xfs: move the xfs_attr_sf_lookup tracepoint
  xfs: return if_data from xfs_idata_realloc
  xfs: make if_data a void pointer
  xfs: fold xfs_rtallocate_extent into xfs_bmap_rtalloc
  xfs: simplify and optimize the RT allocation fallback cascade
  xfs: reorder the minlen and prod calculations in xfs_bmap_rtalloc
  xfs: remove XFS_RTMIN/XFS_RTMAX
  xfs: remove rt-wrappers from xfs_format.h
  xfs: factor out a xfs_rtalloc_sumlevel helper
  xfs: tidy up xfs_rtallocate_extent_exact
  xfs: merge the calls to xfs_rtallocate_range in xfs_rtallocate_block
  xfs: reflow the tail end of xfs_rtallocate_extent_block
  ...
2024-01-10 08:45:22 -08:00
Vishal Verma
4eca0ef49a dax/kmem: allow kmem to add memory with memmap_on_memory
Large amounts of memory managed by the kmem driver may come in via CXL,
and it is often desirable to have the memmap for this memory on the new
memory itself.

Enroll kmem-managed memory for memmap_on_memory semantics if the dax
region originates via CXL.  For non-CXL dax regions, retain the existing
default behavior of hot adding without memmap_on_memory semantics.

Link: https://lkml.kernel.org/r/20231107-vv-kmem_memmap-v10-3-1253ec050ed0@intel.com
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Tested-by: Li Zhijian <lizhijian@fujitsu.com>	[cxl.kmem and nvdimm.kmem]
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Fan Ni <fan.ni@samsung.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 16:51:35 -08:00
Shiyang Ruan
fa422b353d mm, pmem, xfs: Introduce MF_MEM_PRE_REMOVE for unbind
Now, if we suddenly remove a PMEM device(by calling unbind) which
contains FSDAX while programs are still accessing data in this device,
e.g.:
```
 $FSSTRESS_PROG -d $SCRATCH_MNT -n 99999 -p 4 &
 # $FSX_PROG -N 1000000 -o 8192 -l 500000 $SCRATCH_MNT/t001 &
 echo "pfn1.1" > /sys/bus/nd/drivers/nd_pmem/unbind
```
it could come into an unacceptable state:
  1. device has gone but mount point still exists, and umount will fail
       with "target is busy"
  2. programs will hang and cannot be killed
  3. may crash with NULL pointer dereference

To fix this, we introduce a MF_MEM_PRE_REMOVE flag to let it know that we
are going to remove the whole device, and make sure all related processes
could be notified so that they could end up gracefully.

This patch is inspired by Dan's "mm, dax, pmem: Introduce
dev_pagemap_failure()"[1].  With the help of dax_holder and
->notify_failure() mechanism, the pmem driver is able to ask filesystem
on it to unmap all files in use, and notify processes who are using
those files.

Call trace:
trigger unbind
 -> unbind_store()
  -> ... (skip)
   -> devres_release_all()
    -> kill_dax()
     -> dax_holder_notify_failure(dax_dev, 0, U64_MAX, MF_MEM_PRE_REMOVE)
      -> xfs_dax_notify_failure()
      `-> freeze_super()             // freeze (kernel call)
      `-> do xfs rmap
      ` -> mf_dax_kill_procs()
      `  -> collect_procs_fsdax()    // all associated processes
      `  -> unmap_and_kill()
      ` -> invalidate_inode_pages2_range() // drop file's cache
      `-> thaw_super()               // thaw (both kernel & user call)

Introduce MF_MEM_PRE_REMOVE to let filesystem know this is a remove
event.  Use the exclusive freeze/thaw[2] to lock the filesystem to prevent
new dax mapping from being created.  Do not shutdown filesystem directly
if configuration is not supported, or if failure range includes metadata
area.  Make sure all files and processes(not only the current progress)
are handled correctly.  Also drop the cache of associated files before
pmem is removed.

[1]: https://lore.kernel.org/linux-mm/161604050314.1463742.14151665140035795571.stgit@dwillia2-desk3.amr.corp.intel.com/
[2]: https://lore.kernel.org/linux-xfs/169116275623.3187159.16862410128731457358.stg-ugh@frogsfrogsfrogs/

Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-12-07 14:34:26 +05:30
Linus Torvalds
ecae0bd517 Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
 
 - Kemeng Shi has contributed some compation maintenance work in the
   series "Fixes and cleanups to compaction".
 
 - Joel Fernandes has a patchset ("Optimize mremap during mutual
   alignment within PMD") which fixes an obscure issue with mremap()'s
   pagetable handling during a subsequent exec(), based upon an
   implementation which Linus suggested.
 
 - More DAMON/DAMOS maintenance and feature work from SeongJae Park i the
   following patch series:
 
 	mm/damon: misc fixups for documents, comments and its tracepoint
 	mm/damon: add a tracepoint for damos apply target regions
 	mm/damon: provide pseudo-moving sum based access rate
 	mm/damon: implement DAMOS apply intervals
 	mm/damon/core-test: Fix memory leaks in core-test
 	mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
 
 - In the series "Do not try to access unaccepted memory" Adrian Hunter
   provides some fixups for the recently-added "unaccepted memory' feature.
   To increase the feature's checking coverage.  "Plug a few gaps where
   RAM is exposed without checking if it is unaccepted memory".
 
 - In the series "cleanups for lockless slab shrink" Qi Zheng has done
   some maintenance work which is preparation for the lockless slab
   shrinking code.
 
 - Qi Zheng has redone the earlier (and reverted) attempt to make slab
   shrinking lockless in the series "use refcount+RCU method to implement
   lockless slab shrink".
 
 - David Hildenbrand contributes some maintenance work for the rmap code
   in the series "Anon rmap cleanups".
 
 - Kefeng Wang does more folio conversions and some maintenance work in
   the migration code.  Series "mm: migrate: more folio conversion and
   unification".
 
 - Matthew Wilcox has fixed an issue in the buffer_head code which was
   causing long stalls under some heavy memory/IO loads.  Some cleanups
   were added on the way.  Series "Add and use bdev_getblk()".
 
 - In the series "Use nth_page() in place of direct struct page
   manipulation" Zi Yan has fixed a potential issue with the direct
   manipulation of hugetlb page frames.
 
 - In the series "mm: hugetlb: Skip initialization of gigantic tail
   struct pages if freed by HVO" has improved our handling of gigantic
   pages in the hugetlb vmmemmep optimizaton code.  This provides
   significant boot time improvements when significant amounts of gigantic
   pages are in use.
 
 - Matthew Wilcox has sent the series "Small hugetlb cleanups" - code
   rationalization and folio conversions in the hugetlb code.
 
 - Yin Fengwei has improved mlock()'s handling of large folios in the
   series "support large folio for mlock"
 
 - In the series "Expose swapcache stat for memcg v1" Liu Shixin has
   added statistics for memcg v1 users which are available (and useful)
   under memcg v2.
 
 - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
   prctl so that userspace may direct the kernel to not automatically
   propagate the denial to child processes.  The series is named "MDWE
   without inheritance".
 
 - Kefeng Wang has provided the series "mm: convert numa balancing
   functions to use a folio" which does what it says.
 
 - In the series "mm/ksm: add fork-exec support for prctl" Stefan Roesch
   makes is possible for a process to propagate KSM treatment across
   exec().
 
 - Huang Ying has enhanced memory tiering's calculation of memory
   distances.  This is used to permit the dax/kmem driver to use "high
   bandwidth memory" in addition to Optane Data Center Persistent Memory
   Modules (DCPMM).  The series is named "memory tiering: calculate
   abstract distance based on ACPI HMAT"
 
 - In the series "Smart scanning mode for KSM" Stefan Roesch has
   optimized KSM by teaching it to retain and use some historical
   information from previous scans.
 
 - Yosry Ahmed has fixed some inconsistencies in memcg statistics in the
   series "mm: memcg: fix tracking of pending stats updates values".
 
 - In the series "Implement IOCTL to get and optionally clear info about
   PTEs" Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits
   us to atomically read-then-clear page softdirty state.  This is mainly
   used by CRIU.
 
 - Hugh Dickins contributed the series "shmem,tmpfs: general maintenance"
   - a bunch of relatively minor maintenance tweaks to this code.
 
 - Matthew Wilcox has increased the use of the VMA lock over file-backed
   page faults in the series "Handle more faults under the VMA lock".  Some
   rationalizations of the fault path became possible as a result.
 
 - In the series "mm/rmap: convert page_move_anon_rmap() to
   folio_move_anon_rmap()" David Hildenbrand has implemented some cleanups
   and folio conversions.
 
 - In the series "various improvements to the GUP interface" Lorenzo
   Stoakes has simplified and improved the GUP interface with an eye to
   providing groundwork for future improvements.
 
 - Andrey Konovalov has sent along the series "kasan: assorted fixes and
   improvements" which does those things.
 
 - Some page allocator maintenance work from Kemeng Shi in the series
   "Two minor cleanups to break_down_buddy_pages".
 
 - In thes series "New selftest for mm" Breno Leitao has developed
   another MM self test which tickles a race we had between madvise() and
   page faults.
 
 - In the series "Add folio_end_read" Matthew Wilcox provides cleanups
   and an optimization to the core pagecache code.
 
 - Nhat Pham has added memcg accounting for hugetlb memory in the series
   "hugetlb memcg accounting".
 
 - Cleanups and rationalizations to the pagemap code from Lorenzo
   Stoakes, in the series "Abstract vma_merge() and split_vma()".
 
 - Audra Mitchell has fixed issues in the procfs page_owner code's new
   timestamping feature which was causing some misbehaviours.  In the
   series "Fix page_owner's use of free timestamps".
 
 - Lorenzo Stoakes has fixed the handling of new mappings of sealed files
   in the series "permit write-sealed memfd read-only shared mappings".
 
 - Mike Kravetz has optimized the hugetlb vmemmap optimization in the
   series "Batch hugetlb vmemmap modification operations".
 
 - Some buffer_head folio conversions and cleanups from Matthew Wilcox in
   the series "Finish the create_empty_buffers() transition".
 
 - As a page allocator performance optimization Huang Ying has added
   automatic tuning to the allocator's per-cpu-pages feature, in the series
   "mm: PCP high auto-tuning".
 
 - Roman Gushchin has contributed the patchset "mm: improve performance
   of accounted kernel memory allocations" which improves their performance
   by ~30% as measured by a micro-benchmark.
 
 - folio conversions from Kefeng Wang in the series "mm: convert page
   cpupid functions to folios".
 
 - Some kmemleak fixups in Liu Shixin's series "Some bugfix about
   kmemleak".
 
 - Qi Zheng has improved our handling of memoryless nodes by keeping them
   off the allocation fallback list.  This is done in the series "handle
   memoryless nodes more appropriately".
 
 - khugepaged conversions from Vishal Moola in the series "Some
   khugepaged folio conversions".
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZULEMwAKCRDdBJ7gKXxA
 jhQHAQCYpD3g849x69DmHnHWHm/EHQLvQmRMDeYZI+nx/sCJOwEAw4AKg0Oemv9y
 FgeUPAD1oasg6CP+INZvCj34waNxwAc=
 =E+Y4
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Many singleton patches against the MM code. The patch series which are
  included in this merge do the following:

   - Kemeng Shi has contributed some compation maintenance work in the
     series 'Fixes and cleanups to compaction'

   - Joel Fernandes has a patchset ('Optimize mremap during mutual
     alignment within PMD') which fixes an obscure issue with mremap()'s
     pagetable handling during a subsequent exec(), based upon an
     implementation which Linus suggested

   - More DAMON/DAMOS maintenance and feature work from SeongJae Park i
     the following patch series:

	mm/damon: misc fixups for documents, comments and its tracepoint
	mm/damon: add a tracepoint for damos apply target regions
	mm/damon: provide pseudo-moving sum based access rate
	mm/damon: implement DAMOS apply intervals
	mm/damon/core-test: Fix memory leaks in core-test
	mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval

   - In the series 'Do not try to access unaccepted memory' Adrian
     Hunter provides some fixups for the recently-added 'unaccepted
     memory' feature. To increase the feature's checking coverage. 'Plug
     a few gaps where RAM is exposed without checking if it is
     unaccepted memory'

   - In the series 'cleanups for lockless slab shrink' Qi Zheng has done
     some maintenance work which is preparation for the lockless slab
     shrinking code

   - Qi Zheng has redone the earlier (and reverted) attempt to make slab
     shrinking lockless in the series 'use refcount+RCU method to
     implement lockless slab shrink'

   - David Hildenbrand contributes some maintenance work for the rmap
     code in the series 'Anon rmap cleanups'

   - Kefeng Wang does more folio conversions and some maintenance work
     in the migration code. Series 'mm: migrate: more folio conversion
     and unification'

   - Matthew Wilcox has fixed an issue in the buffer_head code which was
     causing long stalls under some heavy memory/IO loads. Some cleanups
     were added on the way. Series 'Add and use bdev_getblk()'

   - In the series 'Use nth_page() in place of direct struct page
     manipulation' Zi Yan has fixed a potential issue with the direct
     manipulation of hugetlb page frames

   - In the series 'mm: hugetlb: Skip initialization of gigantic tail
     struct pages if freed by HVO' has improved our handling of gigantic
     pages in the hugetlb vmmemmep optimizaton code. This provides
     significant boot time improvements when significant amounts of
     gigantic pages are in use

   - Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
     rationalization and folio conversions in the hugetlb code

   - Yin Fengwei has improved mlock()'s handling of large folios in the
     series 'support large folio for mlock'

   - In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
     added statistics for memcg v1 users which are available (and
     useful) under memcg v2

   - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
     prctl so that userspace may direct the kernel to not automatically
     propagate the denial to child processes. The series is named 'MDWE
     without inheritance'

   - Kefeng Wang has provided the series 'mm: convert numa balancing
     functions to use a folio' which does what it says

   - In the series 'mm/ksm: add fork-exec support for prctl' Stefan
     Roesch makes is possible for a process to propagate KSM treatment
     across exec()

   - Huang Ying has enhanced memory tiering's calculation of memory
     distances. This is used to permit the dax/kmem driver to use 'high
     bandwidth memory' in addition to Optane Data Center Persistent
     Memory Modules (DCPMM). The series is named 'memory tiering:
     calculate abstract distance based on ACPI HMAT'

   - In the series 'Smart scanning mode for KSM' Stefan Roesch has
     optimized KSM by teaching it to retain and use some historical
     information from previous scans

   - Yosry Ahmed has fixed some inconsistencies in memcg statistics in
     the series 'mm: memcg: fix tracking of pending stats updates
     values'

   - In the series 'Implement IOCTL to get and optionally clear info
     about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
     which permits us to atomically read-then-clear page softdirty
     state. This is mainly used by CRIU

   - Hugh Dickins contributed the series 'shmem,tmpfs: general
     maintenance', a bunch of relatively minor maintenance tweaks to
     this code

   - Matthew Wilcox has increased the use of the VMA lock over
     file-backed page faults in the series 'Handle more faults under the
     VMA lock'. Some rationalizations of the fault path became possible
     as a result

   - In the series 'mm/rmap: convert page_move_anon_rmap() to
     folio_move_anon_rmap()' David Hildenbrand has implemented some
     cleanups and folio conversions

   - In the series 'various improvements to the GUP interface' Lorenzo
     Stoakes has simplified and improved the GUP interface with an eye
     to providing groundwork for future improvements

   - Andrey Konovalov has sent along the series 'kasan: assorted fixes
     and improvements' which does those things

   - Some page allocator maintenance work from Kemeng Shi in the series
     'Two minor cleanups to break_down_buddy_pages'

   - In thes series 'New selftest for mm' Breno Leitao has developed
     another MM self test which tickles a race we had between madvise()
     and page faults

   - In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
     and an optimization to the core pagecache code

   - Nhat Pham has added memcg accounting for hugetlb memory in the
     series 'hugetlb memcg accounting'

   - Cleanups and rationalizations to the pagemap code from Lorenzo
     Stoakes, in the series 'Abstract vma_merge() and split_vma()'

   - Audra Mitchell has fixed issues in the procfs page_owner code's new
     timestamping feature which was causing some misbehaviours. In the
     series 'Fix page_owner's use of free timestamps'

   - Lorenzo Stoakes has fixed the handling of new mappings of sealed
     files in the series 'permit write-sealed memfd read-only shared
     mappings'

   - Mike Kravetz has optimized the hugetlb vmemmap optimization in the
     series 'Batch hugetlb vmemmap modification operations'

   - Some buffer_head folio conversions and cleanups from Matthew Wilcox
     in the series 'Finish the create_empty_buffers() transition'

   - As a page allocator performance optimization Huang Ying has added
     automatic tuning to the allocator's per-cpu-pages feature, in the
     series 'mm: PCP high auto-tuning'

   - Roman Gushchin has contributed the patchset 'mm: improve
     performance of accounted kernel memory allocations' which improves
     their performance by ~30% as measured by a micro-benchmark

   - folio conversions from Kefeng Wang in the series 'mm: convert page
     cpupid functions to folios'

   - Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
     kmemleak'

   - Qi Zheng has improved our handling of memoryless nodes by keeping
     them off the allocation fallback list. This is done in the series
     'handle memoryless nodes more appropriately'

   - khugepaged conversions from Vishal Moola in the series 'Some
     khugepaged folio conversions'"

[ bcachefs conflicts with the dynamically allocated shrinkers have been
  resolved as per Stephen Rothwell in

     https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/

  with help from Qi Zheng.

  The clone3 test filtering conflict was half-arsed by yours truly ]

* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
  mm/damon/sysfs: update monitoring target regions for online input commit
  mm/damon/sysfs: remove requested targets when online-commit inputs
  selftests: add a sanity check for zswap
  Documentation: maple_tree: fix word spelling error
  mm/vmalloc: fix the unchecked dereference warning in vread_iter()
  zswap: export compression failure stats
  Documentation: ubsan: drop "the" from article title
  mempolicy: migration attempt to match interleave nodes
  mempolicy: mmap_lock is not needed while migrating folios
  mempolicy: alloc_pages_mpol() for NUMA policy without vma
  mm: add page_rmappable_folio() wrapper
  mempolicy: remove confusing MPOL_MF_LAZY dead code
  mempolicy: mpol_shared_policy_init() without pseudo-vma
  mempolicy trivia: use pgoff_t in shared mempolicy tree
  mempolicy trivia: slightly more consistent naming
  mempolicy trivia: delete those ancient pr_debug()s
  mempolicy: fix migrate_pages(2) syscall return nr_failed
  kernfs: drop shared NUMA mempolicy hooks
  hugetlbfs: drop shared NUMA mempolicy pretence
  mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
  ...
2023-11-02 19:38:47 -10:00
Huang Ying
6bc2cfdf82 dax, kmem: calculate abstract distance with general interface
Previously, a fixed abstract distance MEMTIER_DEFAULT_DAX_ADISTANCE is
used for slow memory type in kmem driver.  This limits the usage of kmem
driver, for example, it cannot be used for HBM (high bandwidth memory).

So, we use the general abstract distance calculation mechanism in kmem
drivers to get more accurate abstract distance on systems with proper
support.  The original MEMTIER_DEFAULT_DAX_ADISTANCE is used as fallback
only.

Now, multiple memory types may be managed by kmem.  These memory types are
put into the "kmem_memory_types" list and protected by
kmem_memory_type_lock.

Link: https://lkml.kernel.org/r/20230926060628.265989-5-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Tested-by: Bharata B Rao <bharata@amd.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Rafael J Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-16 15:44:39 -07:00
Justin Stitt
75b3d5dc08 dax: refactor deprecated strncpy
`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

`dax_id->dev_name` is expected to be NUL-terminated and has been zero-allocated.

A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on the destination buffer. Moreover, due to
`dax_id` being zero-allocated the padding behavior of `strncpy` is not
needed and a simple 1:1 replacement of strncpy -> strscpy should
suffice.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2023-09-27 10:33:46 -07:00
Matthew Wilcox (Oracle)
1d024e7a8d mm: remove enum page_entry_size
Remove the unnecessary encoding of page order into an enum and pass the
page order directly.  That lets us get rid of pe_order().

The switch constructs have to be changed to if/else constructs to prevent
GCC from warning on builds with 3-level page tables where PMD_ORDER and
PUD_ORDER have the same value.

If you are looking at this commit because your driver stopped compiling,
look at the previous commit as well and audit your driver to be sure it
doesn't depend on mmap_lock being held in its ->huge_fault method.

[willy@infradead.org: use "order %u" to match the (non dev_t) style]
  Link: https://lkml.kernel.org/r/ZOUYekbtTv+n8hYf@casper.infradead.org
Link: https://lkml.kernel.org/r/20230818202335.2739663-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24 16:20:30 -07:00
Miaohe Lin
bded67f81e memory tier: rename destroy_memory_type() to put_memory_type()
It appears that destroy_memory_type() isn't a very good name because we
usually will not free the memory_type here.  So rename it to a more
appropriate name i.e.  put_memory_type().

Link: https://lkml.kernel.org/r/20230706063905.543800-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Huang, Ying <ying.huang@intel.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Xiao Yang <yangx.jy@fujitsu.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:11 -07:00
Jane Chu
1ea7ca1b09 dax: enable dax fault handler to report VM_FAULT_HWPOISON
When multiple processes mmap() a dax file, then at some point,
a process issues a 'load' and consumes a hwpoison, the process
receives a SIGBUS with si_code = BUS_MCEERR_AR and with si_lsb
set for the poison scope. Soon after, any other process issues
a 'load' to the poisoned page (that is unmapped from the kernel
side by memory_failure), it receives a SIGBUS with
si_code = BUS_ADRERR and without valid si_lsb.

This is confusing to user, and is different from page fault due
to poison in RAM memory, also some helpful information is lost.

Channel dax backend driver's poison detection to the filesystem
such that instead of reporting VM_FAULT_SIGBUS, it could report
VM_FAULT_HWPOISON.

If user level block IO syscalls fail due to poison, the errno will
be converted to EIO to maintain block API consistency.

Signed-off-by: Jane Chu <jane.chu@oracle.com>
Link: https://lore.kernel.org/r/20230615181325.1327259-2-jane.chu@oracle.com
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-26 07:54:23 -06:00
Tarun Sahu
46e66dab85 dax/kmem: Pass valid argument to memory_group_register_static
memory_group_register_static takes maximum number of pages as the argument
while dev_dax_kmem_probe passes total_len (in bytes) as the argument.

IIUC, I don't see any crash/panic impact as such. As,
memory_group_register_static just set the max_pages limit which is used in
auto_movable_zone_for_pfn to determine the zone.

which might cause these condition to behave differently,

This will be true always so jump will happen to kernel_zone
    ...
    if (!auto_movable_can_online_movable(NUMA_NO_NODE, group, nr_pages))
        goto kernel_zone;

    ...
    kernel_zone:
        return default_kernel_zone_for_pfn(nid, pfn, nr_pages);

Here, In below, zone_intersects compare range will be larger as nr_pages
will be higher (derived from total_len passed in dev_dax_kmem_probe).

    ...
    static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn,
    		unsigned long nr_pages)
    {
    	struct pglist_data *pgdat = NODE_DATA(nid);
    	int zid;

    	for (zid = 0; zid < ZONE_NORMAL; zid++) {
    		struct zone *zone = &pgdat->node_zones[zid];

    		if (zone_intersects(zone, start_pfn, nr_pages))
    			return zone;
    	}

    	return &pgdat->node_zones[ZONE_NORMAL];
    }

Incorrect zone will be returned here, which in later time might cause bigger
problem.

Fixes: eedf634aac ("dax/kmem: use a single static memory group for a single probed unit")
Signed-off-by: Tarun Sahu <tsahu@linux.ibm.com>
Link: https://lore.kernel.org/r/20230621155025.370672-1-tsahu@linux.ibm.com
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-23 01:32:06 -06:00
Dan Williams
2532f41607 dax: Cleanup extra dax_region references
Now that free_dev_dax_id() internally manages the references it needs
the extra references taken by the dax_region drivers are not needed.

Reported-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577285161.1672036.8111253437794419696.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-23 01:03:50 -06:00
Dan Williams
70aab281e1 dax: Introduce alloc_dev_dax_id()
The reference counting of dax_region objects is needlessly complicated,
has lead to confusion [1], and has hidden a bug [2]. Towards cleaning up
that mess introduce alloc_dev_dax_id() to minimize the holding of a
dax_region reference to only what dev_dax_release() needs, the
dax_region->ida.

Part of the reason for the mess was the design to dereference a
dax_region in all cases in free_dev_dax_id() even if the id was
statically assigned by the upper level dax_region driver. Remove the
need to call "is_static(dax_region)" by tracking whether the id is
dynamic directly in the dev_dax instance itself.

With that flag the dax_region pinning and release per dev_dax instance
can move to alloc_dev_dax_id() and free_dev_dax_id() respectively.

A follow-on cleanup address the unnecessary references in the dax_region
setup and drivers.

Fixes: 0f3da14a4f ("device-dax: introduce 'seed' devices")
Link: http://lore.kernel.org/r/20221203095858.612027-1-liuyongqiang13@huawei.com [1]
Link: http://lore.kernel.org/r/3cf0890b-4eb0-e70e-cd9c-2ecc3d496263@hpe.com [2]
Reported-by: Yongqiang Liu <liuyongqiang13@huawei.com>
Reported-by: Paul Cassella <cassella@hpe.com>
Reported-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577284563.1672036.13493034988900989554.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-23 01:03:50 -06:00
Dan Williams
82b4ceeccb dax: Use device_unregister() in unregister_dax_mapping()
Replace an open-coded device_unregister() sequence with the helper.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577283989.1672036.7777592498865470652.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-23 01:03:50 -06:00
Dan Williams
6d24b170a9 dax: Fix dax_mapping_release() use after free
A CONFIG_DEBUG_KOBJECT_RELEASE test of removing a device-dax region
provider (like modprobe -r dax_hmem) yields:

 kobject: 'mapping0' (ffff93eb460e8800): kobject_release, parent 0000000000000000 (delayed 2000)
 [..]
 DEBUG_LOCKS_WARN_ON(1)
 WARNING: CPU: 23 PID: 282 at kernel/locking/lockdep.c:232 __lock_acquire+0x9fc/0x2260
 [..]
 RIP: 0010:__lock_acquire+0x9fc/0x2260
 [..]
 Call Trace:
  <TASK>
 [..]
  lock_acquire+0xd4/0x2c0
  ? ida_free+0x62/0x130
  _raw_spin_lock_irqsave+0x47/0x70
  ? ida_free+0x62/0x130
  ida_free+0x62/0x130
  dax_mapping_release+0x1f/0x30
  device_release+0x36/0x90
  kobject_delayed_cleanup+0x46/0x150

Due to attempting ida_free() on an ida object that has already been
freed. Devices typically only hold a reference on their parent while
registered. If a child needs a parent object to complete its release it
needs to hold a reference that it drops from its release callback.
Arrange for a dax_mapping to pin its parent dev_dax instance until
dax_mapping_release().

Fixes: 0b07ce872a ("device-dax: introduce 'mapping' devices")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577283412.1672036.16111545266174261446.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-23 01:03:50 -06:00
Arnd Bergmann
2d5153526f dax: fix missing-prototype warnings
dev_dax_probe declaration for this function was removed with the only
caller outside of device.c. Mark it static to avoid a W=1
warning:
drivers/dax/device.c:399:5: error: no previous prototype for 'dev_dax_probe'

Similarly, run_dax() causes a warning, but this one is because the
declaration needs to be included:

drivers/dax/super.c:337:6: error: no previous prototype for 'run_dax'

Fixes: 83762cb5c7 ("dax: Kill DEV_DAX_PMEM_COMPAT")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230517125532.931157-1-arnd@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-05-18 17:28:07 -07:00
Linus Torvalds
7c3dc440b1 cxl for v6.3
- CXL RAM region enumeration: instantiate 'struct cxl_region' objects
   for platform firmware created memory regions
 
 - CXL RAM region provisioning: complement the existing PMEM region
   creation support with RAM region support
 
 - "Soft Reservation" policy change: Online (memory hot-add)
   soft-reserved memory (EFI_MEMORY_SP) by default, but still allow for
   setting aside such memory for dedicated access via device-dax.
 
 - CXL Events and Interrupts: Takeover CXL event handling from
   platform-firmware (ACPI calls this CXL Memory Error Reporting) and
   export CXL Events via Linux Trace Events.
 
 - Convey CXL _OSC results to drivers: Similar to PCI, let the CXL
   subsystem interrogate the result of CXL _OSC negotiation.
 
 - Emulate CXL DVSEC Range Registers as "decoders": Allow for
   first-generation devices that pre-date the definition of the CXL HDM
   Decoder Capability to translate the CXL DVSEC Range Registers into
   'struct cxl_decoder' objects.
 
 - Set timestamp: Per spec, set the device timestamp in case of hotplug,
   or if platform-firwmare failed to set it.
 
 - General fixups: linux-next build issues, non-urgent fixes for
   pre-production hardware, unit test fixes, spelling and debug message
   improvements.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQSbo+XnGs+rwLz9XGXfioYZHlFsZwUCY/WYcgAKCRDfioYZHlFs
 Z6m3APkBUtiEEm1o8ikdu5llUS1OTLBwqjJDwGMTyf8X/WDXhgD+J2mLsCgARS7X
 5IS0RAtefutrW5sQpUucPM7QiLuraAY=
 =kOXC
 -----END PGP SIGNATURE-----

Merge tag 'cxl-for-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull Compute Express Link (CXL) updates from Dan Williams:
 "To date Linux has been dependent on platform-firmware to map CXL RAM
  regions and handle events / errors from devices. With this update we
  can now parse / update the CXL memory layout, and report events /
  errors from devices. This is a precursor for the CXL subsystem to
  handle the end-to-end "RAS" flow for CXL memory. i.e. the flow that
  for DDR-attached-DRAM is handled by the EDAC driver where it maps
  system physical address events to a field-replaceable-unit (FRU /
  endpoint device). In general, CXL has the potential to standardize
  what has historically been a pile of memory-controller-specific error
  handling logic.

  Another change of note is the default policy for handling RAM-backed
  device-dax instances. Previously the default access mode was "device",
  mmap(2) a device special file to access memory. The new default is
  "kmem" where the address range is assigned to the core-mm via
  add_memory_driver_managed(). This saves typical users from wondering
  why their platform memory is not visible via free(1) and stuck behind
  a device-file. At the same time it allows expert users to deploy
  policy to, for example, get dedicated access to high performance
  memory, or hide low performance memory from general purpose kernel
  allocations. This affects not only CXL, but also systems with
  high-bandwidth-memory that platform-firmware tags with the
  EFI_MEMORY_SP (special purpose) designation.

  Summary:

   - CXL RAM region enumeration: instantiate 'struct cxl_region' objects
     for platform firmware created memory regions

   - CXL RAM region provisioning: complement the existing PMEM region
     creation support with RAM region support

   - "Soft Reservation" policy change: Online (memory hot-add)
     soft-reserved memory (EFI_MEMORY_SP) by default, but still allow
     for setting aside such memory for dedicated access via device-dax.

   - CXL Events and Interrupts: Takeover CXL event handling from
     platform-firmware (ACPI calls this CXL Memory Error Reporting) and
     export CXL Events via Linux Trace Events.

   - Convey CXL _OSC results to drivers: Similar to PCI, let the CXL
     subsystem interrogate the result of CXL _OSC negotiation.

   - Emulate CXL DVSEC Range Registers as "decoders": Allow for
     first-generation devices that pre-date the definition of the CXL
     HDM Decoder Capability to translate the CXL DVSEC Range Registers
     into 'struct cxl_decoder' objects.

   - Set timestamp: Per spec, set the device timestamp in case of
     hotplug, or if platform-firwmare failed to set it.

   - General fixups: linux-next build issues, non-urgent fixes for
     pre-production hardware, unit test fixes, spelling and debug
     message improvements"

* tag 'cxl-for-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (66 commits)
  dax/kmem: Fix leak of memory-hotplug resources
  cxl/mem: Add kdoc param for event log driver state
  cxl/trace: Add serial number to trace points
  cxl/trace: Add host output to trace points
  cxl/trace: Standardize device information output
  cxl/pci: Remove locked check for dvsec_range_allowed()
  cxl/hdm: Add emulation when HDM decoders are not committed
  cxl/hdm: Create emulated cxl_hdm for devices that do not have HDM decoders
  cxl/hdm: Emulate HDM decoder from DVSEC range registers
  cxl/pci: Refactor cxl_hdm_decode_init()
  cxl/port: Export cxl_dvsec_rr_decode() to cxl_port
  cxl/pci: Break out range register decoding from cxl_hdm_decode_init()
  cxl: add RAS status unmasking for CXL
  cxl: remove unnecessary calling of pci_enable_pcie_error_reporting()
  dax/hmem: build hmem device support as module if possible
  dax: cxl: add CXL_REGION dependency
  cxl: avoid returning uninitialized error code
  cxl/pmem: Fix nvdimm registration races
  cxl/mem: Fix UAPI command comment
  cxl/uapi: Tag commands from cxl_query_cmd()
  ...
2023-02-25 09:19:23 -08:00
Linus Torvalds
a93e884edf Driver core changes for 6.3-rc1
Here is the large set of driver core changes for 6.3-rc1.
 
 There's a lot of changes this development cycle, most of the work falls
 into two different categories:
   - fw_devlink fixes and updates.  This has gone through numerous review
     cycles and lots of review and testing by lots of different devices.
     Hopefully all should be good now, and Saravana will be keeping a
     watch for any potential regression on odd embedded systems.
   - driver core changes to work to make struct bus_type able to be moved
     into read-only memory (i.e. const)  The recent work with Rust has
     pointed out a number of areas in the driver core where we are
     passing around and working with structures that really do not have
     to be dynamic at all, and they should be able to be read-only making
     things safer overall.  This is the contuation of that work (started
     last release with kobject changes) in moving struct bus_type to be
     constant.  We didn't quite make it for this release, but the
     remaining patches will be finished up for the release after this
     one, but the groundwork has been laid for this effort.
 
 Other than that we have in here:
   - debugfs memory leak fixes in some subsystems
   - error path cleanups and fixes for some never-able-to-be-hit
     codepaths.
   - cacheinfo rework and fixes
   - Other tiny fixes, full details are in the shortlog
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCY/ipdg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ynL3gCgwzbcWu0So3piZyLiJKxsVo9C2EsAn3sZ9gN6
 6oeFOjD3JDju3cQsfGgd
 =Su6W
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.3-rc1.

  There's a lot of changes this development cycle, most of the work
  falls into two different categories:

   - fw_devlink fixes and updates. This has gone through numerous review
     cycles and lots of review and testing by lots of different devices.
     Hopefully all should be good now, and Saravana will be keeping a
     watch for any potential regression on odd embedded systems.

   - driver core changes to work to make struct bus_type able to be
     moved into read-only memory (i.e. const) The recent work with Rust
     has pointed out a number of areas in the driver core where we are
     passing around and working with structures that really do not have
     to be dynamic at all, and they should be able to be read-only
     making things safer overall. This is the contuation of that work
     (started last release with kobject changes) in moving struct
     bus_type to be constant. We didn't quite make it for this release,
     but the remaining patches will be finished up for the release after
     this one, but the groundwork has been laid for this effort.

  Other than that we have in here:

   - debugfs memory leak fixes in some subsystems

   - error path cleanups and fixes for some never-able-to-be-hit
     codepaths.

   - cacheinfo rework and fixes

   - Other tiny fixes, full details are in the shortlog

  All of these have been in linux-next for a while with no reported
  problems"

[ Geert Uytterhoeven points out that that last sentence isn't true, and
  that there's a pending report that has a fix that is queued up - Linus ]

* tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits)
  debugfs: drop inline constant formatting for ERR_PTR(-ERROR)
  OPP: fix error checking in opp_migrate_dentry()
  debugfs: update comment of debugfs_rename()
  i3c: fix device.h kernel-doc warnings
  dma-mapping: no need to pass a bus_type into get_arch_dma_ops()
  driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place
  Revert "driver core: add error handling for devtmpfs_create_node()"
  Revert "devtmpfs: add debug info to handle()"
  Revert "devtmpfs: remove return value of devtmpfs_delete_node()"
  driver core: cpu: don't hand-override the uevent bus_type callback.
  devtmpfs: remove return value of devtmpfs_delete_node()
  devtmpfs: add debug info to handle()
  driver core: add error handling for devtmpfs_create_node()
  driver core: bus: update my copyright notice
  driver core: bus: add bus_get_dev_root() function
  driver core: bus: constify bus_unregister()
  driver core: bus: constify some internal functions
  driver core: bus: constify bus_get_kset()
  driver core: bus: constify bus_register/unregister_notifier()
  driver core: remove private pointer from struct bus_type
  ...
2023-02-24 12:58:55 -08:00
Linus Torvalds
3822a7c409 - Daniel Verkamp has contributed a memfd series ("mm/memfd: add
F_SEAL_EXEC") which permits the setting of the memfd execute bit at
   memfd creation time, with the option of sealing the state of the X bit.
 
 - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset()
   thread-safe for pmd unshare") which addresses a rare race condition
   related to PMD unsharing.
 
 - Several folioification patch serieses from Matthew Wilcox, Vishal
   Moola, Sidhartha Kumar and Lorenzo Stoakes
 
 - Johannes Weiner has a series ("mm: push down lock_page_memcg()") which
   does perform some memcg maintenance and cleanup work.
 
 - SeongJae Park has added DAMOS filtering to DAMON, with the series
   "mm/damon/core: implement damos filter".  These filters provide users
   with finer-grained control over DAMOS's actions.  SeongJae has also done
   some DAMON cleanup work.
 
 - Kairui Song adds a series ("Clean up and fixes for swap").
 
 - Vernon Yang contributed the series "Clean up and refinement for maple
   tree".
 
 - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series.  It
   adds to MGLRU an LRU of memcgs, to improve the scalability of global
   reclaim.
 
 - David Hildenbrand has added some userfaultfd cleanup work in the
   series "mm: uffd-wp + change_protection() cleanups".
 
 - Christoph Hellwig has removed the generic_writepages() library
   function in the series "remove generic_writepages".
 
 - Baolin Wang has performed some maintenance on the compaction code in
   his series "Some small improvements for compaction".
 
 - Sidhartha Kumar is doing some maintenance work on struct page in his
   series "Get rid of tail page fields".
 
 - David Hildenbrand contributed some cleanup, bugfixing and
   generalization of pte management and of pte debugging in his series "mm:
   support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap
   PTEs".
 
 - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation
   flag in the series "Discard __GFP_ATOMIC".
 
 - Sergey Senozhatsky has improved zsmalloc's memory utilization with his
   series "zsmalloc: make zspage chain size configurable".
 
 - Joey Gouly has added prctl() support for prohibiting the creation of
   writeable+executable mappings.  The previous BPF-based approach had
   shortcomings.  See "mm: In-kernel support for memory-deny-write-execute
   (MDWE)".
 
 - Waiman Long did some kmemleak cleanup and bugfixing in the series
   "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF".
 
 - T.J.  Alumbaugh has contributed some MGLRU cleanup work in his series
   "mm: multi-gen LRU: improve".
 
 - Jiaqi Yan has provided some enhancements to our memory error
   statistics reporting, mainly by presenting the statistics on a per-node
   basis.  See the series "Introduce per NUMA node memory error
   statistics".
 
 - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog
   regression in compaction via his series "Fix excessive CPU usage during
   compaction".
 
 - Christoph Hellwig does some vmalloc maintenance work in the series
   "cleanup vfree and vunmap".
 
 - Christoph Hellwig has removed block_device_operations.rw_page() in ths
   series "remove ->rw_page".
 
 - We get some maple_tree improvements and cleanups in Liam Howlett's
   series "VMA tree type safety and remove __vma_adjust()".
 
 - Suren Baghdasaryan has done some work on the maintainability of our
   vm_flags handling in the series "introduce vm_flags modifier functions".
 
 - Some pagemap cleanup and generalization work in Mike Rapoport's series
   "mm, arch: add generic implementation of pfn_valid() for FLATMEM" and
   "fixups for generic implementation of pfn_valid()"
 
 - Baoquan He has done some work to make /proc/vmallocinfo and
   /proc/kcore better represent the real state of things in his series
   "mm/vmalloc.c: allow vread() to read out vm_map_ram areas".
 
 - Jason Gunthorpe rationalized the GUP system's interface to the rest of
   the kernel in the series "Simplify the external interface for GUP".
 
 - SeongJae Park wishes to migrate people from DAMON's debugfs interface
   over to its sysfs interface.  To support this, we'll temporarily be
   printing warnings when people use the debugfs interface.  See the series
   "mm/damon: deprecate DAMON debugfs interface".
 
 - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes
   and clean-ups" series.
 
 - Huang Ying has provided a dramatic reduction in migration's TLB flush
   IPI rates with the series "migrate_pages(): batch TLB flushing".
 
 - Arnd Bergmann has some objtool fixups in "objtool warning fixes".
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCY/PoPQAKCRDdBJ7gKXxA
 jlvpAPsFECUBBl20qSue2zCYWnHC7Yk4q9ytTkPB/MMDrFEN9wD/SNKEm2UoK6/K
 DmxHkn0LAitGgJRS/W9w81yrgig9tAQ=
 =MlGs
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Daniel Verkamp has contributed a memfd series ("mm/memfd: add
   F_SEAL_EXEC") which permits the setting of the memfd execute bit at
   memfd creation time, with the option of sealing the state of the X
   bit.

 - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset()
   thread-safe for pmd unshare") which addresses a rare race condition
   related to PMD unsharing.

 - Several folioification patch serieses from Matthew Wilcox, Vishal
   Moola, Sidhartha Kumar and Lorenzo Stoakes

 - Johannes Weiner has a series ("mm: push down lock_page_memcg()")
   which does perform some memcg maintenance and cleanup work.

 - SeongJae Park has added DAMOS filtering to DAMON, with the series
   "mm/damon/core: implement damos filter".

   These filters provide users with finer-grained control over DAMOS's
   actions. SeongJae has also done some DAMON cleanup work.

 - Kairui Song adds a series ("Clean up and fixes for swap").

 - Vernon Yang contributed the series "Clean up and refinement for maple
   tree".

 - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It
   adds to MGLRU an LRU of memcgs, to improve the scalability of global
   reclaim.

 - David Hildenbrand has added some userfaultfd cleanup work in the
   series "mm: uffd-wp + change_protection() cleanups".

 - Christoph Hellwig has removed the generic_writepages() library
   function in the series "remove generic_writepages".

 - Baolin Wang has performed some maintenance on the compaction code in
   his series "Some small improvements for compaction".

 - Sidhartha Kumar is doing some maintenance work on struct page in his
   series "Get rid of tail page fields".

 - David Hildenbrand contributed some cleanup, bugfixing and
   generalization of pte management and of pte debugging in his series
   "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with
   swap PTEs".

 - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation
   flag in the series "Discard __GFP_ATOMIC".

 - Sergey Senozhatsky has improved zsmalloc's memory utilization with
   his series "zsmalloc: make zspage chain size configurable".

 - Joey Gouly has added prctl() support for prohibiting the creation of
   writeable+executable mappings.

   The previous BPF-based approach had shortcomings. See "mm: In-kernel
   support for memory-deny-write-execute (MDWE)".

 - Waiman Long did some kmemleak cleanup and bugfixing in the series
   "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF".

 - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series
   "mm: multi-gen LRU: improve".

 - Jiaqi Yan has provided some enhancements to our memory error
   statistics reporting, mainly by presenting the statistics on a
   per-node basis. See the series "Introduce per NUMA node memory error
   statistics".

 - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog
   regression in compaction via his series "Fix excessive CPU usage
   during compaction".

 - Christoph Hellwig does some vmalloc maintenance work in the series
   "cleanup vfree and vunmap".

 - Christoph Hellwig has removed block_device_operations.rw_page() in
   ths series "remove ->rw_page".

 - We get some maple_tree improvements and cleanups in Liam Howlett's
   series "VMA tree type safety and remove __vma_adjust()".

 - Suren Baghdasaryan has done some work on the maintainability of our
   vm_flags handling in the series "introduce vm_flags modifier
   functions".

 - Some pagemap cleanup and generalization work in Mike Rapoport's
   series "mm, arch: add generic implementation of pfn_valid() for
   FLATMEM" and "fixups for generic implementation of pfn_valid()"

 - Baoquan He has done some work to make /proc/vmallocinfo and
   /proc/kcore better represent the real state of things in his series
   "mm/vmalloc.c: allow vread() to read out vm_map_ram areas".

 - Jason Gunthorpe rationalized the GUP system's interface to the rest
   of the kernel in the series "Simplify the external interface for
   GUP".

 - SeongJae Park wishes to migrate people from DAMON's debugfs interface
   over to its sysfs interface. To support this, we'll temporarily be
   printing warnings when people use the debugfs interface. See the
   series "mm/damon: deprecate DAMON debugfs interface".

 - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes
   and clean-ups" series.

 - Huang Ying has provided a dramatic reduction in migration's TLB flush
   IPI rates with the series "migrate_pages(): batch TLB flushing".

 - Arnd Bergmann has some objtool fixups in "objtool warning fixes".

* tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits)
  include/linux/migrate.h: remove unneeded externs
  mm/memory_hotplug: cleanup return value handing in do_migrate_range()
  mm/uffd: fix comment in handling pte markers
  mm: change to return bool for isolate_movable_page()
  mm: hugetlb: change to return bool for isolate_hugetlb()
  mm: change to return bool for isolate_lru_page()
  mm: change to return bool for folio_isolate_lru()
  objtool: add UACCESS exceptions for __tsan_volatile_read/write
  kmsan: disable ftrace in kmsan core code
  kasan: mark addr_has_metadata __always_inline
  mm: memcontrol: rename memcg_kmem_enabled()
  sh: initialize max_mapnr
  m68k/nommu: add missing definition of ARCH_PFN_OFFSET
  mm: percpu: fix incorrect size in pcpu_obj_full_size()
  maple_tree: reduce stack usage with gcc-9 and earlier
  mm: page_alloc: call panic() when memoryless node allocation fails
  mm: multi-gen LRU: avoid futile retries
  migrate_pages: move THP/hugetlb migration support check to simplify code
  migrate_pages: batch flushing TLB
  migrate_pages: share more code between _unmap and _move
  ...
2023-02-23 17:09:35 -08:00
Linus Torvalds
8cc01d43f8 RCU pull request for v6.3
This pull request contains the following branches:
 
 doc.2023.01.05a: Documentation updates.
 
 fixes.2023.01.23a: Miscellaneous fixes, perhaps most notably:
 
 o	Throttling callback invocation based on the number of callbacks
 	that are now ready to invoke instead of on the total number
 	of callbacks.
 
 o	Several patches that suppress false-positive boot-time
 	diagnostics, for example, due to lockdep not yet being
 	initialized.
 
 o	Make expedited RCU CPU stall warnings dump stacks of any tasks
 	that are blocking the stalled grace period.  (Normal RCU CPU
 	stall warnings have doen this for mnay years.)
 
 o	Lazy-callback fixes to avoid delays during boot, suspend, and
 	resume.  (Note that lazy callbacks must be explicitly enabled,
 	so this should not (yet) affect production use cases.)
 
 kvfree.2023.01.03a: Cause kfree_rcu() and friends to take advantage of
 	polled grace periods, thus reducing memory footprint by almost
 	two orders of magnitude, admittedly on a microbenchmark.
 	This series also begins the transition from kfree_rcu(p) to
 	kfree_rcu_mightsleep(p).  This transition was motivated by bugs
 	where kfree_rcu(p), which can block, was typed instead of the
 	intended kfree_rcu(p, rh).
 
 srcu.2023.01.03a: SRCU updates, perhaps most notably fixing a bug that
 	causes SRCU to fail when booted on a system with a non-zero boot
 	CPU.  This surprising situation actually happens for kdump kernels
 	on the powerpc architecture.  It also adds an srcu_down_read()
 	and srcu_up_read(), which act like srcu_read_lock() and
 	srcu_read_unlock(), but allow an SRCU read-side critical section
 	to be handed off from one task to another.
 
 srcu-always.2023.02.02a: Cleans up the now-useless SRCU Kconfig option.
 	There are a few more commits that are not yet acked or pulled
 	into maintainer trees, and these will be in a pull request for
 	a later merge window.
 
 tasks.2023.01.03a: RCU-tasks updates, perhaps most notably these fixes:
 
 o	A strange interaction between PID-namespace unshare and the
 	RCU-tasks grace period that results in a low-probability but
 	very real hang.
 
 o	A race between an RCU tasks rude grace period on a single-CPU
 	system and CPU-hotplug addition of the second CPU that can result
 	in a too-short grace period.
 
 o	A race between shrinking RCU tasks down to a single callback list
 	and queuing a new callback to some other CPU, but where that
 	queuing is delayed for more than an RCU grace period.  This can
 	result in that callback being stranded on the non-boot CPU.
 
 torture.2023.01.05a: Torture-test updates and fixes.
 
 torturescript.2023.01.03a: Torture-test scripting updates and fixes.
 
 stall.2023.01.09a: Provide additional RCU CPU stall-warning information
 	in kernels built with CONFIG_RCU_CPU_STALL_CPUTIME=y, and
 	restore the full five-minute timeout limit for expedited RCU
 	CPU stall warnings.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEbK7UrM+RBIrCoViJnr8S83LZ+4wFAmPq29UTHHBhdWxtY2tA
 a2VybmVsLm9yZwAKCRCevxLzctn7jAhVEACEAKJY1VJ9IUqz7CwzAYkzgRJfiygh
 oDUXmlqtm6ew9pr2GdLUVCVsUSldzBc0K7Djb/G1niv4JPs+v7YwupIV33+UbStU
 Qxt6ztTdxc4lKospLm1+2vF9ZdzVEmiP4wVCc4iDarv5FM3FpWSTNc8+L7qmlC+X
 myjv+GqMTxkXZBvYJOgJGFjDwN8noTd7Fr3mCCVLFm3PXMDa7tcwD6HRP5AqD2N8
 qC5M6LEqepKVGmz0mYMLlSN1GPaqIsEcexIFEazRsPEivPh/iafyQCQ/cqxwhXmV
 vEt7u+dXGZT/oiDq9cJ+/XRDS2RyKIS6dUE14TiiHolDCn1ONESahfA/gXWKykC2
 BaGPfjWXrWv/hwbeZ+8xEdkAvTIV92tGpXir9Fby1Z5PjP3balvrnn6hs5AnQBJb
 NdhRPLzy/dCnEF+CweAYYm1qvTo8cd5nyiNwBZHn7rEAIu3Axrecag1rhFl3AJ07
 cpVMQXZtkQVa2X8aIRTUC+ijX6yIqNaHlu0HqNXgIUTDzL4nv5cMjOMzpNQP9/dZ
 FwAMZYNiOk9IlMiKJ8ZiVcxeiA8ouIBlkYM3k6vGrmiONZ7a/EV/mSHoJqI8bvqr
 AxUIJ2Ayhg3bxPboL5oKgCiLql0A7ZVvz6quX6McitWGMgaSvel1fDzT3TnZd41e
 4AFBFd/+VedUGg==
 =bBYK
 -----END PGP SIGNATURE-----

Merge tag 'rcu.2023.02.10a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull RCU updates from Paul McKenney:

 - Documentation updates

 - Miscellaneous fixes, perhaps most notably:

      - Throttling callback invocation based on the number of callbacks
        that are now ready to invoke instead of on the total number of
        callbacks

      - Several patches that suppress false-positive boot-time
        diagnostics, for example, due to lockdep not yet being
        initialized

      - Make expedited RCU CPU stall warnings dump stacks of any tasks
        that are blocking the stalled grace period. (Normal RCU CPU
        stall warnings have done this for many years)

      - Lazy-callback fixes to avoid delays during boot, suspend, and
        resume. (Note that lazy callbacks must be explicitly enabled, so
        this should not (yet) affect production use cases)

 - Make kfree_rcu() and friends take advantage of polled grace periods,
   thus reducing memory footprint by almost two orders of magnitude,
   admittedly on a microbenchmark

   This also begins the transition from kfree_rcu(p) to
   kfree_rcu_mightsleep(p). This transition was motivated by bugs where
   kfree_rcu(p), which can block, was typed instead of the intended
   kfree_rcu(p, rh)

 - SRCU updates, perhaps most notably fixing a bug that causes SRCU to
   fail when booted on a system with a non-zero boot CPU. This
   surprising situation actually happens for kdump kernels on the
   powerpc architecture

   This also adds an srcu_down_read() and srcu_up_read(), which act like
   srcu_read_lock() and srcu_read_unlock(), but allow an SRCU read-side
   critical section to be handed off from one task to another

 - Clean up the now-useless SRCU Kconfig option

   There are a few more commits that are not yet acked or pulled into
   maintainer trees, and these will be in a pull request for a later
   merge window

 - RCU-tasks updates, perhaps most notably these fixes:

      - A strange interaction between PID-namespace unshare and the
        RCU-tasks grace period that results in a low-probability but
        very real hang

      - A race between an RCU tasks rude grace period on a single-CPU
        system and CPU-hotplug addition of the second CPU that can
        result in a too-short grace period

      - A race between shrinking RCU tasks down to a single callback
        list and queuing a new callback to some other CPU, but where
        that queuing is delayed for more than an RCU grace period. This
        can result in that callback being stranded on the non-boot CPU

 - Torture-test updates and fixes

 - Torture-test scripting updates and fixes

 - Provide additional RCU CPU stall-warning information in kernels built
   with CONFIG_RCU_CPU_STALL_CPUTIME=y, and restore the full five-minute
   timeout limit for expedited RCU CPU stall warnings

* tag 'rcu.2023.02.10a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (80 commits)
  rcu/kvfree: Add kvfree_rcu_mightsleep() and kfree_rcu_mightsleep()
  kernel/notifier: Remove CONFIG_SRCU
  init: Remove "select SRCU"
  fs/quota: Remove "select SRCU"
  fs/notify: Remove "select SRCU"
  fs/btrfs: Remove "select SRCU"
  fs: Remove CONFIG_SRCU
  drivers/pci/controller: Remove "select SRCU"
  drivers/net: Remove "select SRCU"
  drivers/md: Remove "select SRCU"
  drivers/hwtracing/stm: Remove "select SRCU"
  drivers/dax: Remove "select SRCU"
  drivers/base: Remove CONFIG_SRCU
  rcu: Disable laziness if lazy-tracking says so
  rcu: Track laziness during boot and suspend
  rcu: Remove redundant call to rcu_boost_kthread_setaffinity()
  rcu: Allow up to five minutes expedited RCU CPU stall-warning timeouts
  rcu: Align the output of RCU CPU stall warning messages
  rcu: Add RCU stall diagnosis information
  sched: Add helper nr_context_switches_cpu()
  ...
2023-02-21 10:45:51 -08:00
Dan Williams
e686c32590 dax/kmem: Fix leak of memory-hotplug resources
While experimenting with CXL region removal the following corruption of
/proc/iomem appeared.

Before:
f010000000-f04fffffff : CXL Window 0
  f010000000-f02fffffff : region4
    f010000000-f02fffffff : dax4.0
      f010000000-f02fffffff : System RAM (kmem)

After (modprobe -r cxl_test):
f010000000-f02fffffff : **redacted binary garbage**
  f010000000-f02fffffff : System RAM (kmem)

...and testing further the same is visible with persistent memory
assigned to kmem:

Before:
480000000-243fffffff : Persistent Memory
  480000000-57e1fffff : namespace3.0
  580000000-243fffffff : dax3.0
    580000000-243fffffff : System RAM (kmem)

After (ndctl disable-region all):
480000000-243fffffff : Persistent Memory
  580000000-243fffffff : ***redacted binary garbage***
    580000000-243fffffff : System RAM (kmem)

The corrupted data is from a use-after-free of the "dax4.0" and "dax3.0"
resources, and it also shows that the "System RAM (kmem)" resource is
not being removed. The bug does not appear after "modprobe -r kmem", it
requires the parent of "dax4.0" and "dax3.0" to be removed which
re-parents the leaked "System RAM (kmem)" instances. Those in turn
reference the freed resource as a parent.

First up for the fix is release_mem_region_adjustable() needs to
reliably delete the resource inserted by add_memory_driver_managed().
That is thwarted by a check for IORESOURCE_SYSRAM that predates the
dax/kmem driver, from commit:

65c7878413 ("kernel, resource: check for IORESOURCE_SYSRAM in release_mem_region_adjustable")

That appears to be working around the behavior of HMM's
"MEMORY_DEVICE_PUBLIC" facility that has since been deleted. With that
check removed the "System RAM (kmem)" resource gets removed, but
corruption still occurs occasionally because the "dax" resource is not
reliably removed.

The dax range information is freed before the device is unregistered, so
the driver can not reliably recall (another use after free) what it is
meant to release. Lastly if that use after free got lucky, the driver
was covering up the leak of "System RAM (kmem)" due to its use of
release_resource() which detaches, but does not free, child resources.
The switch to remove_resource() forces remove_memory() to be responsible
for the deletion of the resource added by add_memory_driver_managed().

Fixes: c2f3011ee6 ("device-dax: add an allocation interface for device-dax instances")
Cc: <stable@vger.kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167653656244.3147810.5705900882794040229.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-17 14:58:01 -08:00
Arnd Bergmann
0c16c83ed5 dax: cxl: add CXL_REGION dependency
There is already a dependency on CXL_REGION, which depends on CXL_BUS,
but since CXL_REGION is a 'bool' symbol, it's possible to configure
DAX as built-in even though CXL itself is a loadable module:

x86_64-linux-ld: drivers/dax/cxl.o: in function `cxl_dax_region_probe':
cxl.c:(.text+0xb): undefined reference to `to_cxl_dax_region'
x86_64-linux-ld: drivers/dax/cxl.o: in function `cxl_dax_region_driver_init':
cxl.c:(.init.text+0x10): undefined reference to `__cxl_driver_register'
x86_64-linux-ld: drivers/dax/cxl.o: in function `cxl_dax_region_driver_exit':
cxl.c:(.exit.text+0x9): undefined reference to `cxl_driver_unregister'

Prevent this with another depndency on the tristate symbol.

Fixes: 09d09e04d2 ("cxl/dax: Create dax devices for CXL RAM regions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230214103054.1082908-1-arnd@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-14 08:38:20 -08:00
Dan Williams
09d09e04d2 cxl/dax: Create dax devices for CXL RAM regions
While platform firmware takes some responsibility for mapping the RAM
capacity of CXL devices present at boot, the OS is responsible for
mapping the remainder and hot-added devices. Platform firmware is also
responsible for identifying the platform general purpose memory pool,
typically DDR attached DRAM, and arranging for the remainder to be 'Soft
Reserved'. That reservation allows the CXL subsystem to route the memory
to core-mm via memory-hotplug (dax_kmem), or leave it for dedicated
access (device-dax).

The new 'struct cxl_dax_region' object allows for a CXL memory resource
(region) to be published, but also allow for udev and module policy to
act on that event. It also prevents cxl_core.ko from having a module
loading dependency on any drivers/dax/ modules.

Tested-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/167602003896.1924368.10335442077318970468.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-10 17:33:45 -08:00
Dan Williams
e9ee9fe3a9 dax: Assign RAM regions to memory-hotplug by default
The default mode for device-dax instances is backwards for RAM-regions
as evidenced by the fact that it tends to catch end users by surprise.
"Where is my memory?". Recall that platforms are increasingly shipping
with performance-differentiated memory pools beyond typical DRAM and
NUMA effects. This includes HBM (high-bandwidth-memory) and CXL (dynamic
interleave, varied media types, and future fabric attached
possibilities).

For this reason the EFI_MEMORY_SP (EFI Special Purpose Memory => Linux
'Soft Reserved') attribute is expected to be applied to all memory-pools
that are not the general purpose pool. This designation gives an
Operating System a chance to defer usage of a memory pool until later in
the boot process where its performance properties can be interrogated
and administrator policy can be applied.

'Soft Reserved' memory can be anything from too limited and precious to
be part of the general purpose pool (HBM), too slow to host hot kernel
data structures (some PMEM media), or anything in between. However, in
the absence of an explicit policy, the memory should at least be made
usable by default. The current device-dax default hides all
non-general-purpose memory behind a device interface.

The expectation is that the distribution of users that want the memory
online by default vs device-dedicated-access by default follows the
Pareto principle. A small number of enlightened users may want to do
userspace memory management through a device, but general users just
want the kernel to make the memory available with an option to get more
advanced later.

Arrange for all device-dax instances not backed by PMEM to default to
attaching to the dax_kmem driver. From there the baseline memory hotplug
policy (CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE / memhp_default_state=)
gates whether the memory comes online or stays offline. Where, if it
stays offline, it can be reliably converted back to device-mode where it
can be partitioned, or fronted by a userspace allocator.

So, if someone wants device-dax instances for their 'Soft Reserved'
memory:

1/ Build a kernel with CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=n or boot
   with memhp_default_state=offline, or roll the dice and hope that the
   kernel has not pinned a page in that memory before step 2.

2/ Write a udev rule to convert the target dax device(s) from
   'system-ram' mode to 'devdax' mode:

   daxctl reconfigure-device $dax -m devdax -f

Cc: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Gregory Price <gregory.price@memverge.com>
Tested-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167602003336.1924368.6809503401422267885.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-10 17:33:40 -08:00