Commit Graph

278 Commits

Author SHA1 Message Date
Miguel Ojeda
a126eca844 rust: avoid unused import warning in rusttest
When compiling for the `rusttest` target, the `core::ptr` import is
unused since its only use happens in the `reserve()` method which is
not compiled in that target:

    warning: unused import: `core::ptr`
    --> rust/kernel/alloc/vec_ext.rs:7:5
      |
    7 | use core::ptr;
      |     ^^^^^^^^^
      |
      = note: `#[warn(unused_imports)]` on by default

Thus clean it.

Fixes: 97ab3e8eec ("rust: alloc: fix dangling pointer in VecExt<T>::reserve()")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Danilo Krummrich <dakr@redhat.com>
Link: https://lore.kernel.org/r/20240519210735.587323-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-06-11 23:33:28 +02:00
Linus Torvalds
4f05e82003 LoongArch changes for v6.10
1, Select some options in Kconfig;
 2, Give a chance to build with !CONFIG_SMP;
 3, Switch to use built-in rustc target;
 4, Add new supported device nodes to dts;
 5, Some bug fixes and other small changes;
 6, Update the default config file.
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmZKCycWHGNoZW5odWFj
 YWlAa2VybmVsLm9yZwAKCRAChivD8uImeoXWD/9pFhbbJj49T1xiwc2j/XgQL8HI
 s88/h4z5AXEbHFO8XIG1Cpw/Z3a1DsCiWBsOkCogagILzYuN0r7UqcrI02ZoeY6N
 fbuDatB3i+hJWCBzcl1HPkFy/9av4j4EktZs0+X/wVgKkd0aIh78qs8+1RwKhshf
 FoOv+cMu7zFS8Jrt+w16diNCY1JsDv7TCkCVhvJxAodrtGg4oo2NPfrGOrKAP8Dq
 LClvFEqDcXq1kKcipw3Q7BwDlBpJEvLZ0iAl19BnLAmBzI3Wfze9ouoYv8WiUyaY
 br0GPShGf16I3DKtTdHsHH/zmayQ7JSmFzZ9JEHzcBrE4AprfWLuwsUjd2WXDD6U
 wK+p4tWd0AUFf+/h4u1yQB9/rlt+JZ2ny/A2u4YR/BPtthiYqp8SDSH62vpCSFOE
 dByDeTbfjTdJsWr+bsI2gOO0sVwDYpph9SJfAyBn4miKw7v8w+2rI1oqo/ZQkP59
 0SczM9C9jzpgXSGDc4yQbnqoA4KA9U6zljd12mYL5HV/AjhD19va3FmENgByZUuE
 Z7A0RZsiU5T401xEZiOUhwzy9m/USc1O2ivCmeowx9kP/gWic0KeAsmlMiro0jeR
 y9jthci8iOgjjLmCEVC06GWGUojP2roXI/38We6enVevy2GXbEEDRa1QGbQ5ndoJ
 MEPm4NvW1wsBgWIYmg==
 =WR15
 -----END PGP SIGNATURE-----

Merge tag 'loongarch-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Select some options in Kconfig

 - Give a chance to build with !CONFIG_SMP

 - Switch to use built-in rustc target

 - Add new supported device nodes to dts

 - Some bug fixes and other small changes

 - Update the default config file

* tag 'loongarch-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: Update Loongson-3 default config file
  LoongArch: dts: Add new supported device nodes to Loongson-2K2000
  LoongArch: dts: Add new supported device nodes to Loongson-2K0500
  LoongArch: dts: Remove "disabled" state of clock controller node
  LoongArch: rust: Switch to use built-in rustc target
  LoongArch: Fix callchain parse error with kernel tracepoint events again
  LoongArch: Give a chance to build with !CONFIG_SMP
  LoongArch: Select THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
  LoongArch: Select ARCH_WANT_DEFAULT_BPF_JIT
  LoongArch: Select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
  LoongArch: Select ARCH_HAS_FAST_MULTIPLIER
2024-05-22 09:43:07 -07:00
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
ff9a79307f Kbuild updates for v6.10
- Avoid 'constexpr', which is a keyword in C23
 
  - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
    'dt_binding_check'
 
  - Fix weak references to avoid GOT entries in position-independent
    code generation
 
  - Convert the last use of 'optional' property in arch/sh/Kconfig
 
  - Remove support for the 'optional' property in Kconfig
 
  - Remove support for Clang's ThinLTO caching, which does not work with
    the .incbin directive
 
  - Change the semantics of $(src) so it always points to the source
    directory, which fixes Makefile inconsistencies between upstream and
    downstream
 
  - Fix 'make tar-pkg' for RISC-V to produce a consistent package
 
  - Provide reasonable default coverage for objtool, sanitizers, and
    profilers
 
  - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
 
  - Remove the last use of tristate choice in drivers/rapidio/Kconfig
 
  - Various cleanups and fixes in Kconfig
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmZFlGcVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsG8voQALC8NtFpduWVfLRj2Qg6Ll/xf1vX
 2igcTJEOFHkeqXLGoT8dTDKLEipUBUvKyguPq66CGwVTe2g6zy/nUSXeVtFrUsIa
 msLTi8FqhqUo5lodNvGMRf8qqmuqcvnXoiQwIocF92jtsFy14bhiFY+n4HfcFNjj
 GOKwqBZYQUwY/VVb090efc7RfS9c7uwABJSBelSoxg3AGZriwjGy7Pw5aSKGgVYi
 inqL1eR6qwPP6z7CgQWM99soP+zwybFZmnQrsD9SniRBI4rtAat8Ih5jQFaSUFUQ
 lk2w0NQBRFN88/uR2IJ2GWuIlQ74WeJ+QnCqVuQ59tV5zw90wqSmLzngfPD057Dv
 JjNuhk0UyXVtpIg3lRtd4810ppNSTe33b9OM4O2H846W/crju5oDRNDHcflUXcwm
 Rmn5ho1rb5QVzDVejJbgwidnUInSgJ9PZcvXQ/RJVZPhpgsBzAY9pQexG1G3hviw
 y9UDrt6KP6bF9tHjmolmtdIes9Pj0c4dN6/Rdj4HS4hIQ/GDar0tnwvOvtfUctNL
 orJlBsA6GeMmDVXKkR0ytOCWRYqWWbyt8g70RVKQJfuHX7/hGyAQPaQ2/u4mQhC2
 aevYfbNJMj0VDfGz81HDBKFtkc5n+Ite8l157dHEl2LEabkOkRdNVcn7SNbOvZmd
 ZCSnZ31h7woGfNho
 =D5B/
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Avoid 'constexpr', which is a keyword in C23

 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
   'dt_binding_check'

 - Fix weak references to avoid GOT entries in position-independent code
   generation

 - Convert the last use of 'optional' property in arch/sh/Kconfig

 - Remove support for the 'optional' property in Kconfig

 - Remove support for Clang's ThinLTO caching, which does not work with
   the .incbin directive

 - Change the semantics of $(src) so it always points to the source
   directory, which fixes Makefile inconsistencies between upstream and
   downstream

 - Fix 'make tar-pkg' for RISC-V to produce a consistent package

 - Provide reasonable default coverage for objtool, sanitizers, and
   profilers

 - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.

 - Remove the last use of tristate choice in drivers/rapidio/Kconfig

 - Various cleanups and fixes in Kconfig

* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
  kconfig: use sym_get_choice_menu() in sym_check_prop()
  rapidio: remove choice for enumeration
  kconfig: lxdialog: remove initialization with A_NORMAL
  kconfig: m/nconf: merge two item_add_str() calls
  kconfig: m/nconf: remove dead code to display value of bool choice
  kconfig: m/nconf: remove dead code to display children of choice members
  kconfig: gconf: show checkbox for choice correctly
  kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
  Makefile: remove redundant tool coverage variables
  kbuild: provide reasonable defaults for tool coverage
  modules: Drop the .export_symbol section from the final modules
  kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
  kconfig: use sym_get_choice_menu() in conf_write_defconfig()
  kconfig: add sym_get_choice_menu() helper
  kconfig: turn defaults and additional prompt for choice members into error
  kconfig: turn missing prompt for choice members into error
  kconfig: turn conf_choice() into void function
  kconfig: use linked list in sym_set_changed()
  kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
  kconfig: gconf: remove debug code
  ...
2024-05-18 12:39:20 -07:00
Linus Torvalds
2d9db778dd Timers and timekeeping updates:
- Core code:
 
    - Make timekeeping and VDSO time readouts resilent against math overflow:
 
      In guest context the kernel is prone to math overflow when the host
      defers the timer interrupt due to overload, malfunction or malice.
 
      This can be mitigated by checking the clocksource delta for the
      maximum deferrement which is readily available. If that value is
      exceeded then the code uses a slowpath function which can handle the
      multiplication overflow.
 
      This functionality is enabled unconditionally in the kernel, but made
      conditional in the VDSO code. The latter is conditional because it
      allows architectures to optimize the check so it is not causing
      performance regressions.
 
      On X86 this is achieved by reworking the existing check for negative
      TSC deltas as a negative delta obviously exceeds the maximum
      deferrement when it is evaluated as an unsigned value. That avoids two
      conditionals in the hotpath and allows to hide both the negative delta
      and the large delta handling in the same slow path.
 
    - Add an initial minimal ktime_t abstraction for Rust
 
    - The usual boring cleanups and enhancements
 
  - Drivers:
 
    - Boring updates to device trees and trivial enhancements in various
      drivers.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmZBErUTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoZVhD/9iUPzcGNgqGqcO1bXy6dH4xLpeec6o
 2En1vg45DOaygN7DFxkoei20KJtfdFeaaEDH8UqmOfPcpLIuVAd0yqhgDQtx6ZcO
 XNd09SFDInzUt1Ot/WcoXp5N6Wt3vyEgUAlIN1fQdbaZ3fh6OhGhXXCRfiRCGXU1
 ea2pSunLuRf1pKU0AYhGIexnZMOHC4NmVXw/m+WNw5DJrmWB+OaNFKfMoQjtQ1HD
 Vgyr2RALHnIeXm60y2j3dD7TWGXICE/edzOd7pEyg5LFXsmcp388eu/DEdOq3OTV
 tsHLgIi05GJym3dykPBVwZk09M5oVNNfkg9zDxHWhSLkEJmc4QUaH3dgM8uBoaRW
 pS3LaO3ePxWmtAOdSNKFY6xnl6df+PYJoZcIF/GuXgty7im+VLK9C4M05mSjey00
 omcEywvmGdFezY6D9MmjjhFa+q2v9zpRjFpCWaIv3DQdAaDPrOzBk4SSqHZOV4lq
 +hp7ar1mTn1FPrXBouwyOgSOUANISV5cy/QuwOtrVIuVR4rWFVgfWo/7J32/q5Ik
 XBR0lTdQy1Biogf6xy0HCY+4wItOLTqEXXqeknHSMJpDzj5uZglZemgKbix1wVJ9
 8YlD85Q7sktlPmiLMKV9ra0MKVyXDoIrgt4hX98A8M12q9bNdw23x0p0jkJHwGha
 ZYUyX+XxKgOJug==
 =pL+S
 -----END PGP SIGNATURE-----

Merge tag 'timers-core-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timers and timekeeping updates from Thomas Gleixner:
 "Core code:

   - Make timekeeping and VDSO time readouts resilent against math
     overflow:

     In guest context the kernel is prone to math overflow when the host
     defers the timer interrupt due to overload, malfunction or malice.

     This can be mitigated by checking the clocksource delta for the
     maximum deferrement which is readily available. If that value is
     exceeded then the code uses a slowpath function which can handle
     the multiplication overflow.

     This functionality is enabled unconditionally in the kernel, but
     made conditional in the VDSO code. The latter is conditional
     because it allows architectures to optimize the check so it is not
     causing performance regressions.

     On X86 this is achieved by reworking the existing check for
     negative TSC deltas as a negative delta obviously exceeds the
     maximum deferrement when it is evaluated as an unsigned value. That
     avoids two conditionals in the hotpath and allows to hide both the
     negative delta and the large delta handling in the same slow path.

   - Add an initial minimal ktime_t abstraction for Rust

   - The usual boring cleanups and enhancements

  Drivers:

   - Boring updates to device trees and trivial enhancements in various
     drivers"

* tag 'timers-core-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  clocksource/drivers/arm_arch_timer: Mark hisi_161010101_oem_info const
  clocksource/drivers/timer-ti-dm: Remove an unused field in struct dmtimer
  clocksource/drivers/renesas-ostm: Avoid reprobe after successful early probe
  clocksource/drivers/renesas-ostm: Allow OSTM driver to reprobe for RZ/V2H(P) SoC
  dt-bindings: timer: renesas: ostm: Document Renesas RZ/V2H(P) SoC
  rust: time: doc: Add missing C header links
  clocksource: Make the int help prompt unit readable in ncurses
  hrtimer: Rename __hrtimer_hres_active() to hrtimer_hres_active()
  timerqueue: Remove never used function timerqueue_node_expires()
  rust: time: Add Ktime
  vdso: Fix powerpc build U64_MAX undeclared error
  clockevents: Convert s[n]printf() to sysfs_emit()
  clocksource: Convert s[n]printf() to sysfs_emit()
  clocksource: Make watchdog and suspend-timing multiplication overflow safe
  timekeeping: Let timekeeping_cycles_to_ns() handle both under and overflow
  timekeeping: Make delta calculation overflow safe
  timekeeping: Prepare timekeeping_cycles_to_ns() for overflow safety
  timekeeping: Fold in timekeeping_delta_to_ns()
  timekeeping: Consolidate timekeeping helpers
  timekeeping: Refactor timekeeping helpers
  ...
2024-05-14 09:27:40 -07:00
WANG Rui
8f8d74ee11 LoongArch: rust: Switch to use built-in rustc target
This commit switches to use the LoongArch's built-in rustc target
'loongarch64-unknown-none-softfloat'. The Rust samples have been tested.

Acked-by: Miguel Ojeda <ojeda@kernel.org>
Tested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-05-14 12:24:18 +08:00
Linus Torvalds
8f5b5f7811 Rust changes for v6.10
The most notable change is the drop of the 'alloc' in-tree fork. This
 is nicely reflected in the diffstat as a ~10k lines drop. In turn, this
 makes the version upgrades way simpler and smaller in the future, e.g.
 the latest one in commit 56f64b3706 ("rust: upgrade to Rust 1.78.0").
 
 More importantly, this increases the chances that a newer compiler
 version just works, which in turn means supporting several compiler
 versions is easier now. Thus we will look into finally setting a minimum
 version in the near future.
 
 Toolchain and infrastructure:
 
  - Upgrade to Rust 1.78.0.
 
    This time around, due to how the kernel and Rust schedules have
    aligned, there are two upgrades in fact. These allow us to remove one
    more unstable feature ('offset_of') from the list, among other
    improvements.
 
  - Drop 'alloc' in-tree fork of the standard library crate, which means
    all the unstable features used by 'alloc' (~30 language ones, ~60
    library ones) are not a concern anymore.
 
  - Support DWARFv5 via the '-Zdwarf-version' flag.
 
  - Support zlib and zstd debuginfo compression via the
    '-Zdebuginfo-compression' flag.
 
 'kernel' crate:
 
  - Support allocation flags ('GFP_*'), particularly in 'Box' (via
    'BoxExt'), 'Vec' (via 'VecExt'), 'Arc' and 'UniqueArc', as well as in
    the 'init' module APIs.
 
  - Remove usage of the 'allocator_api' unstable feature.
 
  - Remove 'try_' prefix in allocation APIs' names.
 
  - Add 'VecExt' (an extension trait) to be able to drop the 'alloc'
    fork.
 
  - Add the '{make,to}_{upper,lower}case()' methods to 'CStr'/'CString'.
 
  - Add the 'as_ptr' method to 'ThisModule'.
 
  - Add the 'from_raw' method to 'ArcBorrow'.
 
  - Add the 'into_unique_or_drop' method to 'Arc'.
 
  - Display column number in the 'dbg!' macro output by applying the
    equivalent change done to the standard library one.
 
  - Migrate 'Work' to '#[pin_data]' thanks to the changes in the 'macros'
    crate, which allows to remove an unsafe call in its 'new' associated
    function.
 
  - Prevent namespacing issues when using the '[try_][pin_]init!' macros
    by changing the generated name of guard variables.
 
  - Make the 'get' method in 'Opaque' const.
 
  - Implement the 'Default' trait for 'LockClassKey'.
 
  - Remove unneeded 'kernel::prelude' imports from doctests.
 
  - Remove redundant imports.
 
 'macros' crate:
 
  - Add 'decl_generics' to 'parse_generics()' to support default values,
    and use that to allow them in '#[pin_data]'.
 
 Helpers:
 
  - Trivial English grammar fix.
 
 Documentation:
 
  - Add section on Rust Kselftests to the "Testing" document.
 
  - Expand the "Abstractions vs. bindings" section of the "General
    Information" document.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEPjU5OPd5QIZ9jqqOGXyLc2htIW0FAmZBIzoACgkQGXyLc2ht
 IW2/7hAAz5fRsx1M1b/JU3P3lc3XKUaFCmAWJX6F+sNHp8vNeFYNzVZ3ylk6Z4zB
 idkTq0Y5Rlc8ejryHiEMaY3X7Zrh0yt3G/AzKZqZx54IAPUp59BRSvG3+SJanQ7p
 Gjy+cCXweLtYjF79Au5Ejt52gV+JAwPtGLkbl1skNs0jPr4rqm+Zg4bPhE5Sr0Eh
 mh2VxcHf3rbIVhBYJTYGNpsnQYZNwfPDJ+bRudYp1BymLYOG8A328ocvU19BM63+
 6FFQBLgB3N8OS+Mw0c8AeFVNkeCw4NesmIkBMco8wm8QXyLz1zjg948LT9ogPCgB
 5eC41yAxa83uPdt8L034YNfJa+IgFleZp339QKW2+vXHks43M8IMLq9WP7GU84M1
 Axu5ekl5sR6awOk0265Zc1ghkOTQREIi0kiqtNBh9wc/qILAD2DyYoy1td9ch1Qi
 BBNxyKYaMx9z+7mhK4ksTbRb+VrdDmFPDhXOIJD5zg4yrLZOM6Mb/O+BnSD2pxa3
 6cUGwfQTv0hbBTeY4ZgdNgFu2YJ/9rqACKtULoaT0AID/d8I3fxc7J35AWnqeC/x
 nALHTa2JMkBvN03Afn0wCVuXbdLW0/9DCGnuuhYMn0DhFC/uuKicsvwfjcGSKnPN
 iaRJoRCYKjlc0AJSYHhavgyp2R9HnVM0E53PC3ubjiKz5DsaRDU=
 =j6/D
 -----END PGP SIGNATURE-----

Merge tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux

Pull Rust updates from Miguel Ojeda:
 "The most notable change is the drop of the 'alloc' in-tree fork. This
  is nicely reflected in the diffstat as a ~10k lines drop. In turn,
  this makes the version upgrades way simpler and smaller in the future,
  e.g. the latest one in commit 56f64b3706 ("rust: upgrade to Rust
  1.78.0").

  More importantly, this increases the chances that a newer compiler
  version just works, which in turn means supporting several compiler
  versions is easier now. Thus we will look into finally setting a
  minimum version in the near future.

  Toolchain and infrastructure:

   - Upgrade to Rust 1.78.0

     This time around, due to how the kernel and Rust schedules have
     aligned, there are two upgrades in fact. These allow us to remove
     one more unstable feature ('offset_of') from the list, among other
     improvements

   - Drop 'alloc' in-tree fork of the standard library crate, which
     means all the unstable features used by 'alloc' (~30 language ones,
     ~60 library ones) are not a concern anymore

   - Support DWARFv5 via the '-Zdwarf-version' flag

   - Support zlib and zstd debuginfo compression via the
     '-Zdebuginfo-compression' flag

  'kernel' crate:

   - Support allocation flags ('GFP_*'), particularly in 'Box' (via
     'BoxExt'), 'Vec' (via 'VecExt'), 'Arc' and 'UniqueArc', as well as
     in the 'init' module APIs

   - Remove usage of the 'allocator_api' unstable feature

   - Remove 'try_' prefix in allocation APIs' names

   - Add 'VecExt' (an extension trait) to be able to drop the 'alloc'
     fork

   - Add the '{make,to}_{upper,lower}case()' methods to 'CStr'/'CString'

   - Add the 'as_ptr' method to 'ThisModule'

   - Add the 'from_raw' method to 'ArcBorrow'

   - Add the 'into_unique_or_drop' method to 'Arc'

   - Display column number in the 'dbg!' macro output by applying the
     equivalent change done to the standard library one

   - Migrate 'Work' to '#[pin_data]' thanks to the changes in the
     'macros' crate, which allows to remove an unsafe call in its 'new'
     associated function

   - Prevent namespacing issues when using the '[try_][pin_]init!'
     macros by changing the generated name of guard variables

   - Make the 'get' method in 'Opaque' const

   - Implement the 'Default' trait for 'LockClassKey'

   - Remove unneeded 'kernel::prelude' imports from doctests

   - Remove redundant imports

  'macros' crate:

   - Add 'decl_generics' to 'parse_generics()' to support default
     values, and use that to allow them in '#[pin_data]'

  Helpers:

   - Trivial English grammar fix

  Documentation:

   - Add section on Rust Kselftests to the 'Testing' document

   - Expand the 'Abstractions vs. bindings' section of the 'General
     Information' document"

* tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux: (31 commits)
  rust: alloc: fix dangling pointer in VecExt<T>::reserve()
  rust: upgrade to Rust 1.78.0
  rust: kernel: remove redundant imports
  rust: sync: implement `Default` for `LockClassKey`
  docs: rust: extend abstraction and binding documentation
  docs: rust: Add instructions for the Rust kselftest
  rust: remove unneeded `kernel::prelude` imports from doctests
  rust: update `dbg!()` to format column number
  rust: helpers: Fix grammar in comment
  rust: init: change the generated name of guard variables
  rust: sync: add `Arc::into_unique_or_drop`
  rust: sync: add `ArcBorrow::from_raw`
  rust: types: Make Opaque::get const
  rust: kernel: remove usage of `allocator_api` unstable feature
  rust: init: update `init` module to take allocation flags
  rust: sync: update `Arc` and `UniqueArc` to take allocation flags
  rust: alloc: update `VecExt` to take allocation flags
  rust: alloc: introduce the `BoxExt` trait
  rust: alloc: introduce allocation flags
  rust: alloc: remove our fork of the `alloc` crate
  ...
2024-05-13 15:13:54 -07:00
Masahiro Yamada
b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00
Danilo Krummrich
97ab3e8eec rust: alloc: fix dangling pointer in VecExt<T>::reserve()
Currently, a Vec<T>'s ptr value, after calling Vec<T>::new(), is
initialized to Unique::dangling(). Hence, in VecExt<T>::reserve(), we're
passing a dangling pointer (instead of NULL) to krealloc() whenever a new
Vec<T>'s backing storage is allocated through VecExt<T> extension
functions.

This only works as long as align_of::<T>(), used by Unique::dangling() to
derive the dangling pointer, resolves to a value between 0x0 and
ZERO_SIZE_PTR (0x10) and krealloc() hence treats it the same as a NULL
pointer however.

This isn't a case we should rely on, since there may be types whose
alignment may exceed the range still covered by krealloc(), plus other
kernel allocators are not as tolerant either.

Instead, pass a real NULL pointer to krealloc_aligned() if Vec<T>'s
capacity is zero.

Fixes: 5ab560ce12 ("rust: alloc: update `VecExt` to take allocation flags")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240501134834.22323-1-dakr@redhat.com
[ Solved `use` conflict and applied the `if`-instead-of-`match` change
  discussed in the list. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-08 00:43:30 +02:00
Miguel Ojeda
00280272a0 rust: kernel: remove redundant imports
Rust's `unused_imports` lint covers both unused and redundant imports.
In the upcoming 1.78.0, the lint detects more cases of redundant imports
[1], e.g.:

    error: the item `bindings` is imported redundantly
      --> rust/kernel/print.rs:38:9
       |
    38 |     use crate::bindings;
       |         ^^^^^^^^^^^^^^^ the item `bindings` is already defined by prelude

Most cases are `use crate::bindings`, plus a few other items like `Box`.
Thus clean them up.

Note that, in the `bindings` case, the message "defined by prelude"
above means the extern prelude, i.e. the `--extern` flags we pass.

Link: https://github.com/rust-lang/rust/pull/117772 [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240401212303.537355-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 19:22:25 +02:00
Miguel Ojeda
7c81aa85ee rust: sync: implement Default for LockClassKey
In the upcoming Rust 1.78.0, Clippy suggests to implement `Default` even
when `new()` is `const`, since `Default::default()` may call `const`
functions even if it is not `const` itself [1]:

    error: you should consider adding a `Default` implementation for `LockClassKey`
      --> rust/kernel/sync.rs:31:5
       |
    31 | /     pub const fn new() -> Self {
    32 | |         Self(Opaque::uninit())
    33 | |     }
       | |_____^

Thus implement it.

Link: https://github.com/rust-lang/rust-clippy/pull/10903 [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240401212303.537355-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 19:22:25 +02:00
Nell Shamrell-Harrington
4a2ae88051 rust: remove unneeded kernel::prelude imports from doctests
Rust doctests implicitly include `kernel::prelude::*`.

Removes explicit `kernel::prelude` imports from doctests.

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1064
Signed-off-by: Nell Shamrell-Harrington <nells@linux.microsoft.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240411225331.274662-1-nells@linux.microsoft.com
[ Add it back for `module_phy_driver`'s example since it is within a `mod`,
  and thus it cannot be removed. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:09:04 +02:00
Raghav Narang
ea175b2d6f rust: update dbg!() to format column number
In Rust 1.76.0, the `dbg!()` macro was updated to also format the column
number. The reason cited was usage of a few characters worth of
horizontal space while allowing direct jumps to the source location. [1]

Link: https://github.com/rust-lang/rust/pull/114962 [1]
Link: https://github.com/Rust-for-Linux/linux/issues/1065
Signed-off-by: Raghav Narang <dev@raxyte.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/eba70259-9b10-4bf7-ac4f-d7accf6b8891@smtp-relay.sendinblue.com
[ Fixed commit author name and removed spurious newline in message. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:09:04 +02:00
Thorsten Blum
84373132b8 rust: helpers: Fix grammar in comment
s/directly the bindings/the bindings directly/

Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240411205428.537700-1-thorsten.blum@toblux.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:09:04 +02:00
Benno Lossin
9218cf826f rust: init: change the generated name of guard variables
The initializers created by the `[try_][pin_]init!` macros utilize the
guard pattern to drop already initialized fields, when initialization
fails mid-way. These guards are generated to have the same name as the
field that they handle. To prevent namespacing issues [1] when the
field name is the same as e.g. a constant name, add `__` as a prefix
and `_guard` as the suffix.

[ Gary says:

   "Here's the simplified example:

    ```
    macro_rules! f {
        () => {
            let a = 1;
            let _: u32 = a;
        }
    }

    const a: u64 = 1;

    fn main() {
        f!();
    }
    ```

    The `a` in `f` have a different hygiene so normally it is scoped to the
    macro expansion and wouldn't escape. Interestingly a constant is still
    preferred despite the hygiene so constants escaped into the macro,
    leading to the error."

  - Miguel ]

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/rust-for-linux/1e8a2a1f-abbf-44ba-8344-705a9cbb1627@proton.me/ [1]
Link: https://lore.kernel.org/r/20240403194321.88716-1-benno.lossin@proton.me
[ Added Benno's link and Gary's simplified example. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:05:00 +02:00
Alice Ryhl
a0a4e17013 rust: sync: add Arc::into_unique_or_drop
Decrement the refcount of an `Arc`, but handle the case where it hits
zero by taking ownership of the now-unique `Arc`, instead of destroying
and deallocating it.

This is a dependency of the linked list that Rust Binder uses. The
linked list uses this method as part of its `ListArc` abstraction [1].

Boqun Feng has authored the examples.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240402-linked-list-v1-1-b1c59ba7ae3b@google.com [1]
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240402-arc-for-list-v4-2-54db6440a9a9@google.com
[ Replace `try_new` with `new` in example since we now have the new
  allocation APIs. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:04:31 +02:00
Alice Ryhl
51f6af86de rust: sync: add ArcBorrow::from_raw
Allows access to a value in an `Arc` that is currently held as a raw
pointer due to use of `Arc::into_raw`, without destroying or otherwise
consuming that raw pointer.

This is a dependency of the linked list that Rust Binder uses. The
linked list uses this method when iterating over the linked list [1].

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240402-linked-list-v1-6-b1c59ba7ae3b@google.com [1]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240402-arc-for-list-v4-1-54db6440a9a9@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 18:04:28 +02:00
Boqun Feng
be2ca1e039 rust: types: Make Opaque::get const
To support a potential usage:

    static foo: Opaque<Foo> = ..; // Or defined in an extern block.

    ...

    fn bar() {
        let ptr = foo.get();
    }

`Opaque::get` need to be `const`, otherwise compiler will complain
because calls on statics are limited to const functions.

Also `Opaque::get` should be naturally `const` since it's a composition
of two `const` functions: `UnsafeCell::get` and `ptr::cast`.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240401214543.1242286-1-boqun.feng@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-05-05 13:19:37 +02:00
Boqun Feng
ddd9120983 rust: time: doc: Add missing C header links
The definitions related to jiffies are at linux/jiffies.h, and the
definitions related to ktime_t are at linux/ktime.h, since
`kernel::time` provides the functionality dealing with jiffies and
ktime_t, it makes sense to add links to them from Rust's time module.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20240411230801.1504496-2-boqun.feng@gmail.com
2024-05-01 00:04:47 +02:00
Kent Overstreet
53ed0af496 rust: add a rust helper for krealloc()
Memory allocation profiling is turning krealloc() into a nontrivial macro
- so for now, we need a helper for it.

Until we have proper support on the rust side for memory allocation
profiling this does mean that all Rust allocations will be accounted to
the helper.

Link: https://lkml.kernel.org/r/20240321163705.3067592-25-surenb@google.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: "Björn Roy Baron" <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@samsung.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:55:55 -07:00
Aswin Unnikrishnan
19843452dc rust: remove params from module macro example
Remove argument `params` from the `module` macro example, because the
macro does not currently support module parameters since it was not sent
with the initial merge.

Signed-off-by: Aswin Unnikrishnan <aswinunni01@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Cc: stable@vger.kernel.org
Fixes: 1fbde52bde ("rust: add `macros` crate")
Link: https://lore.kernel.org/r/20240419215015.157258-1-aswinunni01@gmail.com
[ Reworded slightly. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-25 17:34:33 +02:00
Miguel Ojeda
50cfe93b01 kbuild: rust: remove unneeded @rustc_cfg to avoid ICE
When KUnit tests are enabled, under very big kernel configurations
(e.g. `allyesconfig`), we can trigger a `rustdoc` ICE [1]:

      RUSTDOC TK rust/kernel/lib.rs
    error: the compiler unexpectedly panicked. this is a bug.

The reason is that this build step has a duplicated `@rustc_cfg` argument,
which contains the kernel configuration, and thus a lot of arguments. The
factor 2 happens to be enough to reach the ICE.

Thus remove the unneeded `@rustc_cfg`. By doing so, we clean up the
command and workaround the ICE.

The ICE has been fixed in the upcoming Rust 1.79 [2].

Cc: stable@vger.kernel.org
Fixes: a66d733da8 ("rust: support running Rust documentation tests as KUnit ones")
Link: https://github.com/rust-lang/rust/issues/122722 [1]
Link: https://github.com/rust-lang/rust/pull/122840 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240422091215.526688-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-23 00:38:55 +02:00
Wedson Almeida Filho
323617f649 rust: kernel: require Send for Module implementations
The thread that calls the module initialisation code when a module is
loaded is not guaranteed [in fact, it is unlikely] to be the same one
that calls the module cleanup code on module unload, therefore, `Module`
implementations must be `Send` to account for them moving from one
thread to another implicitly.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Cc: stable@vger.kernel.org # 6.8.x: df70d04d56: rust: phy: implement `Send` for `Registration`
Cc: stable@vger.kernel.org
Fixes: 247b365dc8 ("rust: add `kernel` crate")
Link: https://lore.kernel.org/r/20240328195457.225001-3-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-23 00:38:43 +02:00
Wedson Almeida Filho
df70d04d56 rust: phy: implement Send for Registration
In preparation for requiring `Send` for `Module` implementations in the
next patch.

Cc: FUJITA Tomonori <fujita.tomonori@gmail.com>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: netdev@vger.kernel.org
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240328195457.225001-2-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-23 00:14:05 +02:00
Wedson Almeida Filho
2c1092853f rust: kernel: remove usage of allocator_api unstable feature
With the adoption of `BoxExt` and `VecExt`, we don't need the functions
provided by this feature (namely the methods prefixed with `try_` and
different allocator per collection instance).

We do need `AllocError`, but we define our own as it is a trivial empty
struct.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-11-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
c34aa00d1d rust: init: update init module to take allocation flags
This is the last component in the conversion for allocators to take
allocation flags as parameters.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-10-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
cc41670e06 rust: sync: update Arc and UniqueArc to take allocation flags
We also remove the `try_` prefix to align with how `Box` and `Vec` are
providing methods now.

`init` is temporarily updated with uses of GFP_KERNEL. These will be
updated in a subsequent patch to take flags as well.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-9-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
5ab560ce12 rust: alloc: update VecExt to take allocation flags
We also rename the methods by removing the `try_` prefix since the names
are available due to our usage of the `no_global_oom_handling` config
when building the `alloc` crate.

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240328013603.206764-8-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
08d3f54928 rust: alloc: introduce the BoxExt trait
Make fallible versions of `new` and `new_uninit` methods available in
`Box` even though it doesn't implement them because we build `alloc`
with the `no_global_oom_handling` config.

They also have an extra `flags` parameter that allows callers to pass
flags to the allocator.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240328013603.206764-7-wedsonaf@gmail.com
[ Used `Box::write()` to avoid one `unsafe` block as suggested by Boqun. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:47:20 +02:00
Wedson Almeida Filho
b6a006e21b rust: alloc: introduce allocation flags
We'll use them when allocating `Box`, `Arc`, and `UniqueArc` instances,
as well as when allocating memory for `Vec` elements. These changes will
come in subsequent patches.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-6-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:05:06 +02:00
Wedson Almeida Filho
9d0441bab7 rust: alloc: remove our fork of the alloc crate
It is not used anymore as `VecExt` now provides the functionality we
depend on.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-5-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:05:00 +02:00
Wedson Almeida Filho
11795ae4cc kbuild: use the upstream alloc crate
Switch away from our fork of the `alloc` crate. We remove it altogether
in the next commit.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-4-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:03:14 +02:00
Wedson Almeida Filho
03989773a9 rust: alloc: introduce the VecExt trait
Make `try_with_capacity`, `try_push`, and `try_extend_from_slice`
methods available in `Vec` even though it doesn't implement them. It is
implemented with `try_reserve` and `push_within_capacity`.

This is in preparation for switching to the upstream `alloc` crate.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Suggested-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-3-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:03:14 +02:00
Wedson Almeida Filho
31d94d8f58 rust: kernel: move allocator module under alloc
We will add more to the `alloc` module in subsequent patches (e.g.,
allocation flags and extension traits).

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-2-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:03:14 +02:00
Benno Lossin
7044dcff83 rust: macros: fix soundness issue in module! macro
The `module!` macro creates glue code that are called by C to initialize
the Rust modules using the `Module::init` function. Part of this glue
code are the local functions `__init` and `__exit` that are used to
initialize/destroy the Rust module.

These functions are safe and also visible to the Rust mod in which the
`module!` macro is invoked. This means that they can be called by other
safe Rust code. But since they contain `unsafe` blocks that rely on only
being called at the right time, this is a soundness issue.

Wrap these generated functions inside of two private modules, this
guarantees that the public functions cannot be called from the outside.
Make the safe functions `unsafe` and add SAFETY comments.

Cc: stable@vger.kernel.org
Reported-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Closes: https://github.com/Rust-for-Linux/linux/issues/629
Fixes: 1fbde52bde ("rust: add `macros` crate")
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240401185222.12015-1-benno.lossin@proton.me
[ Moved `THIS_MODULE` out of the private-in-private modules since it
  should remain public, as Dirk Behme noticed [1]. Capitalized comments,
  avoided newline in non-list SAFETY comments and reworded to add
  Reported-by and newline. ]
Link: https://rust-for-linux.zulipchat.com/#narrow/stream/291565-Help/topic/x/near/433512583 [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 21:13:43 +02:00
Alice Ryhl
48b7f4d29a rust: time: Add Ktime
Introduce a wrapper around `ktime_t` with a few different useful methods.

Rust Binder will use these bindings to compute how many milliseconds a
transaction has been active for when dumping the current state of the
Binder driver. This replicates the logic in C Binder [1].

For a usage example in Rust Binder, see [2].

ktime_get() cannot be safely called in NMI context. This requirement is not
checked by these abstractions, but it is intended that klint [3] or a
similar tool will be used to check it in the future.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20240322-rust-ktime_ms_delta-v2-1-d98de1f7c282@google.com
Link: https://lore.kernel.org/lkml/5ac8c0d09392290be789423f0dd78a520b830fab.1682333709.git.zhangchuang3@xiaomi.com/ [1]
Link: https://r.android.com/3004103 [2]
Link: https://rust-for-linux.com/klint [3]
2024-04-11 23:20:43 +02:00
Benno Lossin
8db31d3f3b rust: workqueue: add #[pin_data] to Work
The previous two patches made it possible to add `#[pin_data]` on
structs with default generic parameter values.
This patch makes `Work` use `#[pin_data]` and removes an invocation of
`pin_init_from_closure`. This function is intended as a low level manual
escape hatch, so it is better to rely on the safe `pin_init!` macro.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240309155243.482334-3-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-07 22:03:42 +02:00
Benno Lossin
22eed6068d rust: macros: allow generic parameter default values in #[pin_data]
Add support for generic parameters defaults in `#[pin_data]` by using
the newly introduced `decl_generics` instead of the `impl_generics`.

Before this would not compile:

    #[pin_data]
    struct Foo<const N: usize = 0> {
        // ...
    }

because it would be expanded to this:

    struct Foo<const N: usize = 0> {
        // ...
    }

    const _: () = {
        struct __ThePinData<const N: usize = 0> {
            __phantom: ::core::marker::PhantomData<fn(Foo<N>) -> Foo<N>>,
        }
        impl<const N: usize = 0> ::core::clone::Clone for __ThePinData<N> {
            fn clone(&self) -> Self {
                *self
            }
        }

        // [...] rest of expansion omitted
    };

The problem is with the `impl<const N: usize = 0>`, since that is
invalid Rust syntax. It should not mention the default value at all,
since default values only make sense on type definitions.

The new `impl_generics` do not contain the default values, thus
generating correct Rust code.

This is used by the next commit that puts `#[pin_data]` on
`kernel::workqueue::Work`.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240309155243.482334-2-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-07 22:03:42 +02:00
Benno Lossin
9762dca54a rust: macros: add decl_generics to parse_generics()
The generic parameters on a type definition can specify default values.
Currently `parse_generics()` cannot handle this though. For example when
parsing the following generics:

    <T: Clone, const N: usize = 0>

The `impl_generics` will be set to `T: Clone, const N: usize = 0` and
`ty_generics` will be set to `T, N`. Now using the `impl_generics` on an
impl block:

    impl<$($impl_generics)*> Foo {}

will result in invalid Rust code, because default values are only
available on type definitions.

Therefore add parsing support for generic parameter default values using
a new kind of generics called `decl_generics` and change the old
behavior of `impl_generics` to not contain the generic parameter default
values.

Now `Generics` has three fields:
- `impl_generics`: the generics with bounds
  (e.g. `T: Clone, const N: usize`)
- `decl_generics`: the generics with bounds and default values
  (e.g. `T: Clone, const N: usize = 0`)
- `ty_generics`:  contains the generics without bounds and without
  default values (e.g. `T, N`)

`impl_generics` is designed to be used on `impl<$impl_generics>`,
`decl_generics` for the type definition, so `struct Foo<$decl_generics>`
and `ty_generics` whenever you use the type, so `Foo<$ty_generics>`.

Here is an example that uses all three different types of generics:

    let (Generics { decl_generics, impl_generics, ty_generics }, rest) = parse_generics(input);
    quote! {
        struct Foo<$($decl_generics)*> {
            // ...
        }

        impl<$impl_generics> Foo<$ty_generics> {
            fn foo() {
                // ...
            }
        }
    }

The next commit contains a fix to the `#[pin_data]` macro making it
compatible with generic parameter default values by relying on this new
behavior.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240309155243.482334-1-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-07 22:03:42 +02:00
Laine Taffin Altman
49ceae68a0 rust: init: remove impl Zeroable for Infallible
In Rust, producing an invalid value of any type is immediate undefined
behavior (UB); this includes via zeroing memory.  Therefore, since an
uninhabited type has no valid values, producing any values at all for it is
UB.

The Rust standard library type `core::convert::Infallible` is uninhabited,
by virtue of having been declared as an enum with no cases, which always
produces uninhabited types in Rust.

The current kernel code allows this UB to be triggered, for example by code
like `Box::<core::convert::Infallible>::init(kernel::init::zeroed())`.

Thus, remove the implementation of `Zeroable` for `Infallible`, thereby
avoiding the unsoundness (potential for future UB).

Cc: stable@vger.kernel.org
Fixes: 38cde0bd7b ("rust: init: add `Zeroable` trait and `init::zeroed` function")
Closes: https://github.com/Rust-for-Linux/pinned-init/pull/13
Signed-off-by: Laine Taffin Altman <alexanderaltman@me.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/CA160A4E-561E-4918-837E-3DCEBA74F808@me.com
[ Reformatted the comment slightly. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-04 12:56:16 +02:00
Danilo Krummrich
a321f3ad0a rust: str: add {make,to}_{upper,lower}case() to CString
Add functions to convert a CString to upper- / lowercase, either
in-place or by creating a copy of the original CString.

Naming follows the one from the Rust stdlib, where functions starting
with 'to' create a copy and functions starting with 'make' perform an
in-place conversion.

This is required by the Nova project (GSP only Rust successor of
Nouveau) to convert stringified enum values (representing different GPU
chipsets) to strings in order to generate the corresponding firmware
paths. See also [1].

Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/String.20manipulation.20in.20kernel.20Rust [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240223163726.12397-1-dakr@redhat.com
[ Reworded to fix typo and to make the link use the `Link:` tag. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-02 17:41:56 +02:00
Miguel Ojeda
b481dd85f5 rust: upgrade to Rust 1.77.1
This is the next upgrade to the Rust toolchain, from 1.76.0 to 1.77.1
(i.e. the latest) [1].

See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").

# Unstable features

The `offset_of` feature (single-field `offset_of!`) that we were using
got stabilized in Rust 1.77.0 [3].

Therefore, now the only unstable features allowed to be used outside the
`kernel` crate is `new_uninit`, though other code to be upstreamed may
increase the list.

Please see [4] for details.

# Required changes

Rust 1.77.0 merged the `unused_tuple_struct_fields` lint into `dead_code`,
thus upgrading it from `allow` to `warn` [5]. In turn, this made `rustc`
complain about the `ThisModule`'s pointer field being never read, but
the previous patch adds the `as_ptr` method to it, needed by Binder [6],
so that we do not need to locally `allow` it.

# Other changes

Rust 1.77.0 introduces the `--check-cfg` feature [7], for which there
is a Call for Testing going on [8]. We were requested to test it and
we found it useful [9] -- we will likely enable it in the future.

# `alloc` upgrade and reviewing

The vast majority of changes are due to our `alloc` fork being upgraded
at once.

There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.

Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.

Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.

To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:

    # Get the difference with respect to the old version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > old.patch
    git -C linux restore rust/alloc

    # Apply this patch.
    git -C linux am rust-upgrade.patch

    # Get the difference with respect to the new version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > new.patch
    git -C linux restore rust/alloc

Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.

Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1770-2024-03-21 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/pull/118799 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/pull/118297 [5]
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/#Z31rust:kernel:lib.rs [6]
Link: https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/check-cfg.html [7]
Link: https://github.com/rust-lang/rfcs/pull/3013#issuecomment-1936648479 [8]
Link: https://github.com/rust-lang/rust/issues/82450#issuecomment-1947462977 [9]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240217002717.57507-1-ojeda@kernel.org
[ Upgraded to 1.77.1. Removed `allow(dead_code)` thanks to the previous
  patch. Reworded accordingly. No changes to `alloc` during the beta. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-03-29 20:12:30 +01:00
Alice Ryhl
d0f0241d8d rust: add Module::as_ptr
This allows you to get a raw pointer to THIS_MODULE for use in unsafe
code. The Rust Binder RFC uses it when defining fops for the binderfs
component [1].

This doesn't really need to go in now - it could go in together with
Rust Binder like how it is sent in the Rust Binder RFC. However, the
upcoming 1.77.0 release of the Rust compiler introduces a new warning,
and applying this patch now will silence that warning. That allows us to
avoid adding the #[allow(dead_code)] annotation seen in [2].

Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/ [1]
Link: https://lore.kernel.org/all/20240217002717.57507-1-ojeda@kernel.org/ [2]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240226-module-as-ptr-v1-1-83bc89213113@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-03-29 18:04:32 +01:00
Linus Torvalds
1d35aae78f Kbuild updates for v6.9
- Generate a list of built DTB files (arch/*/boot/dts/dtbs-list)
 
  - Use more threads when building Debian packages in parallel
 
  - Fix warnings shown during the RPM kernel package uninstallation
 
  - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to
    Makefile
 
  - Support GCC's -fmin-function-alignment flag
 
  - Fix a null pointer dereference bug in modpost
 
  - Add the DTB support to the RPM package
 
  - Various fixes and cleanups in Kconfig
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmX8HGIVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGYfIQAIl/zEFoNVSHGR4TIvO7SIwkT4MM
 VAm0W6XRFaXfIGw8HL/MXe+U9jAyeQ9yL9uUVv8PqFTO+LzBbW1X1X97tlmrlQsC
 7mdxbA1KJXwkwt4wH/8/EZQMwHr327vtVH4AilSm+gAaWMXaSKAye3ulKQQ2gevz
 vP6aOcfbHIWOPdxA53cLdSl9LOGrYNczKySHXKV9O39T81F+ko7wPpdkiMWw5LWG
 ISRCV8bdXli8j10Pmg8jlbevSKl4Z5FG2BVw/Cl8rQ5tBBoCzFsUPnnp9A29G8QP
 OqRhbwxtkSm67BMJAYdHnhjp/l0AOEbmetTGpna+R06hirOuXhR3vc6YXZxhQjff
 LmKaqfG5YchRALS1fNDsRUNIkQxVJade+tOUG+V4WbxHQKWX7Ghu5EDlt2/x7P0p
 +XLPE48HoNQLQOJ+pgIOkaEDl7WLfGhoEtEgprZBuEP2h39xcdbYJyF10ZAAR4UZ
 FF6J9lDHbf7v1uqD2YnAQJQ6jJ06CvN6/s6SdiJnCWSs5cYRW0fnYigSIuwAgGHZ
 c/QFECoGEflXGGuqZDl5iXiIjhWKzH2nADSVEs7maP47vapcMWb9gA7VBNoOr5M0
 IXuFo1khChF4V2pxqlDj3H5TkDlFENYT/Wjh+vvjx8XplKCRKaSh+LaZ39hja61V
 dWH7BPecS44h4KXx
 =tFdl
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Generate a list of built DTB files (arch/*/boot/dts/dtbs-list)

 - Use more threads when building Debian packages in parallel

 - Fix warnings shown during the RPM kernel package uninstallation

 - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to
   Makefile

 - Support GCC's -fmin-function-alignment flag

 - Fix a null pointer dereference bug in modpost

 - Add the DTB support to the RPM package

 - Various fixes and cleanups in Kconfig

* tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (67 commits)
  kconfig: tests: test dependency after shuffling choices
  kconfig: tests: add a test for randconfig with dependent choices
  kconfig: tests: support KCONFIG_SEED for the randconfig runner
  kbuild: rpm-pkg: add dtb files in kernel rpm
  kconfig: remove unneeded menu_is_visible() call in conf_write_defconfig()
  kconfig: check prompt for choice while parsing
  kconfig: lxdialog: remove unused dialog colors
  kconfig: lxdialog: fix button color for blackbg theme
  modpost: fix null pointer dereference
  kbuild: remove GCC's default -Wpacked-bitfield-compat flag
  kbuild: unexport abs_srctree and abs_objtree
  kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1
  kconfig: remove named choice support
  kconfig: use linked list in get_symbol_str() to iterate over menus
  kconfig: link menus to a symbol
  kbuild: fix inconsistent indentation in top Makefile
  kbuild: Use -fmin-function-alignment when available
  alpha: merge two entries for CONFIG_ALPHA_GAMMA
  alpha: merge two entries for CONFIG_ALPHA_EV4
  kbuild: change DTC_FLAGS_<basetarget>.o to take the path relative to $(obj)
  ...
2024-03-21 14:41:00 -07:00
Linus Torvalds
6d75c6f40a arm64 updates for 6.9:
* Reorganise the arm64 kernel VA space and add support for LPA2 (at
   stage 1, KVM stage 2 was merged earlier) - 52-bit VA/PA address range
   with 4KB and 16KB pages
 
 * Enable Rust on arm64
 
 * Support for the 2023 dpISA extensions (data processing ISA), host only
 
 * arm64 perf updates:
 
   - StarFive's StarLink (integrates one or more CPU cores with a shared
     L3 memory system) PMU support
 
   - Enable HiSilicon Erratum 162700402 quirk for HIP09
 
   - Several updates for the HiSilicon PCIe PMU driver
 
   - Arm CoreSight PMU support
 
   - Convert all drivers under drivers/perf/ to use .remove_new()
 
 * Miscellaneous:
 
   - Don't enable workarounds for "rare" errata by default
 
   - Clean up the DAIF flags handling for EL0 returns (in preparation for
     NMI support)
 
   - Kselftest update for ptrace()
 
   - Update some of the sysreg field definitions
 
   - Slight improvement in the code generation for inline asm I/O
     accessors to permit offset addressing
 
   - kretprobes: acquire regs via a BRK exception (previously done via a
     trampoline handler)
 
   - SVE/SME cleanups, comment updates
 
   - Allow CALL_OPS+CC_OPTIMIZE_FOR_SIZE with clang (previously disabled
     due to gcc silently ignoring -falign-functions=N)
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE5RElWfyWxS+3PLO2a9axLQDIXvEFAmXxiSgACgkQa9axLQDI
 XvHd7hAAjQrQqxJogPT2ahM5/gxct8qTrXpIgX0B1Y7bb5R8ztvOUN9MJNuDyRsj
 0s28SSZw387LReM5OUu+U6G/iahcuNAyP/8d9qeac32Tidd255fV3KPEh4C4eC+u
 0HeOqLBZ+stmNoa71tBC2K6SmchizhYyYduvRnri8km8K4OMDawHWqWRTXl0PNRT
 RMVJvZTDJMPfMBFeD4+B7EnSFOoP14tKCw9MZvlbpT2PEV0kINjhCQiojW2jJgqv
 w36vm/dhwsg1avSzT1xhy3KE+m+7n28+IC/wr1HB7c1WumvYKv7Z84ieCp3PlO3Z
 owvVO7dKJC6X3RkoY6Kge5p2RHU6poDerDVHYiAvG+Zi57nrDmHyAubskThsGTGR
 AibSEeJ5nQ0yM6hx7zAIQa5XEo4l0svD1ZM7NynY+5JR44W9cdAH3SnEsvIBMGIf
 /ja+iZ1W4ZQnIESQXD5uDPSxILfqQ8Ebhdorpw+Qg3rB7OhdTdGSSGQCi6V2PcJH
 d/ErFO+i0lFRBPJtBbUAN4EEu3HJcVYEoEnVJYQahC+6KyNGLxO+7L6sH0YO7Pag
 P1LRa6h8ktuBMrbCrOPWdmJYNDYCbb5rRtmcCwO0ItZ4g5tYWp9djFc8pyctCaNB
 MZxxRrUCNwXTOcFTDiYzyk+JCvpf3EvXfvj8AH+P8BMjFWgqHqw=
 =KTD/
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "The major features are support for LPA2 (52-bit VA/PA with 4K and 16K
  pages), the dpISA extension and Rust enabled on arm64. The changes are
  mostly contained within the usual arch/arm64/, drivers/perf, the arm64
  Documentation and kselftests. The exception is the Rust support which
  touches some generic build files.

  Summary:

   - Reorganise the arm64 kernel VA space and add support for LPA2 (at
     stage 1, KVM stage 2 was merged earlier) - 52-bit VA/PA address
     range with 4KB and 16KB pages

   - Enable Rust on arm64

   - Support for the 2023 dpISA extensions (data processing ISA), host
     only

   - arm64 perf updates:

      - StarFive's StarLink (integrates one or more CPU cores with a
        shared L3 memory system) PMU support

      - Enable HiSilicon Erratum 162700402 quirk for HIP09

      - Several updates for the HiSilicon PCIe PMU driver

      - Arm CoreSight PMU support

      - Convert all drivers under drivers/perf/ to use .remove_new()

   - Miscellaneous:

      - Don't enable workarounds for "rare" errata by default

      - Clean up the DAIF flags handling for EL0 returns (in preparation
        for NMI support)

      - Kselftest update for ptrace()

      - Update some of the sysreg field definitions

      - Slight improvement in the code generation for inline asm I/O
        accessors to permit offset addressing

      - kretprobes: acquire regs via a BRK exception (previously done
        via a trampoline handler)

      - SVE/SME cleanups, comment updates

      - Allow CALL_OPS+CC_OPTIMIZE_FOR_SIZE with clang (previously
        disabled due to gcc silently ignoring -falign-functions=N)"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (134 commits)
  Revert "mm: add arch hook to validate mmap() prot flags"
  Revert "arm64: mm: add support for WXN memory translation attribute"
  Revert "ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512"
  ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512
  kselftest/arm64: Add 2023 DPISA hwcap test coverage
  kselftest/arm64: Add basic FPMR test
  kselftest/arm64: Handle FPMR context in generic signal frame parser
  arm64/hwcap: Define hwcaps for 2023 DPISA features
  arm64/ptrace: Expose FPMR via ptrace
  arm64/signal: Add FPMR signal handling
  arm64/fpsimd: Support FEAT_FPMR
  arm64/fpsimd: Enable host kernel access to FPMR
  arm64/cpufeature: Hook new identification registers up to cpufeature
  docs: perf: Fix build warning of hisi-pcie-pmu.rst
  perf: starfive: Only allow COMPILE_TEST for 64-bit architectures
  MAINTAINERS: Add entry for StarFive StarLink PMU
  docs: perf: Add description for StarFive's StarLink PMU
  dt-bindings: perf: starfive: Add JH8100 StarLink PMU
  perf: starfive: Add StarLink PMU support
  docs: perf: Update usage for target filter of hisi-pcie-pmu
  ...
2024-03-14 15:35:42 -07:00
Linus Torvalds
9187210eee Networking changes for 6.9.
Core & protocols
 ----------------
 
  - Large effort by Eric to lower rtnl_lock pressure and remove locks:
 
    - Make commonly used parts of rtnetlink (address, route dumps etc.)
      lockless, protected by RCU instead of rtnl_lock.
 
    - Add a netns exit callback which already holds rtnl_lock,
      allowing netns exit to take rtnl_lock once in the core
      instead of once for each driver / callback.
 
    - Remove locks / serialization in the socket diag interface.
 
    - Remove 6 calls to synchronize_rcu() while holding rtnl_lock.
 
    - Remove the dev_base_lock, depend on RCU where necessary.
 
  - Support busy polling on a per-epoll context basis. Poll length
    and budget parameters can be set independently of system defaults.
 
  - Introduce struct net_hotdata, to make sure read-mostly global config
    variables fit in as few cache lines as possible.
 
  - Add optional per-nexthop statistics to ease monitoring / debug
    of ECMP imbalance problems.
 
  - Support TCP_NOTSENT_LOWAT in MPTCP.
 
  - Ensure that IPv6 temporary addresses' preferred lifetimes are long
    enough, compared to other configured lifetimes, and at least 2 sec.
 
  - Support forwarding of ICMP Error messages in IPSec, per RFC 4301.
 
  - Add support for the independent control state machine for bonding
    per IEEE 802.1AX-2008 5.4.15 in addition to the existing coupled
    control state machine.
 
  - Add "network ID" to MCTP socket APIs to support hosts with multiple
    disjoint MCTP networks.
 
  - Re-use the mono_delivery_time skbuff bit for packets which user
    space wants to be sent at a specified time. Maintain the timing
    information while traversing veth links, bridge etc.
 
  - Take advantage of MSG_SPLICE_PAGES for RxRPC DATA and ACK packets.
 
  - Simplify many places iterating over netdevs by using an xarray
    instead of a hash table walk (hash table remains in place, for
    use on fastpaths).
 
  - Speed up scanning for expired routes by keeping a dedicated list.
 
  - Speed up "generic" XDP by trying harder to avoid large allocations.
 
  - Support attaching arbitrary metadata to netconsole messages.
 
 Things we sprinkled into general kernel code
 --------------------------------------------
 
  - Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce
    VM_SPARSE kind and vm_area_[un]map_pages (used by bpf_arena).
 
  - Rework selftest harness to enable the use of the full range of
    ksft exit code (pass, fail, skip, xfail, xpass).
 
 Netfilter
 ---------
 
  - Allow userspace to define a table that is exclusively owned by a daemon
    (via netlink socket aliveness) without auto-removing this table when
    the userspace program exits. Such table gets marked as orphaned and
    a restarting management daemon can re-attach/regain ownership.
 
  - Speed up element insertions to nftables' concatenated-ranges set type.
    Compact a few related data structures.
 
 BPF
 ---
 
  - Add BPF token support for delegating a subset of BPF subsystem
    functionality from privileged system-wide daemons such as systemd
    through special mount options for userns-bound BPF fs to a trusted
    & unprivileged application.
 
  - Introduce bpf_arena which is sparse shared memory region between BPF
    program and user space where structures inside the arena can have
    pointers to other areas of the arena, and pointers work seamlessly
    for both user-space programs and BPF programs.
 
  - Introduce may_goto instruction that is a contract between the verifier
    and the program. The verifier allows the program to loop assuming it's
    behaving well, but reserves the right to terminate it.
 
  - Extend the BPF verifier to enable static subprog calls in spin lock
    critical sections.
 
  - Support registration of struct_ops types from modules which helps
    projects like fuse-bpf that seeks to implement a new struct_ops type.
 
  - Add support for retrieval of cookies for perf/kprobe multi links.
 
  - Support arbitrary TCP SYN cookie generation / validation in the TC
    layer with BPF to allow creating SYN flood handling in BPF firewalls.
 
  - Add code generation to inline the bpf_kptr_xchg() helper which
    improves performance when stashing/popping the allocated BPF objects.
 
 Wireless
 --------
 
  - Add SPP (signaling and payload protected) AMSDU support.
 
  - Support wider bandwidth OFDMA, as required for EHT operation.
 
 Driver API
 ----------
 
  - Major overhaul of the Energy Efficient Ethernet internals to support
    new link modes (2.5GE, 5GE), share more code between drivers
    (especially those using phylib), and encourage more uniform behavior.
    Convert and clean up drivers.
 
  - Define an API for querying per netdev queue statistics from drivers.
 
  - IPSec: account in global stats for fully offloaded sessions.
 
  - Create a concept of Ethernet PHY Packages at the Device Tree level,
    to allow parameterizing the existing PHY package code.
 
  - Enable Rx hashing (RSS) on GTP protocol fields.
 
 Misc
 ----
 
  - Improvements and refactoring all over networking selftests.
 
  - Create uniform module aliases for TC classifiers, actions,
    and packet schedulers to simplify creating modprobe policies.
 
  - Address all missing MODULE_DESCRIPTION() warnings in networking.
 
  - Extend the Netlink descriptions in YAML to cover message encapsulation
    or "Netlink polymorphism", where interpretation of nested attributes
    depends on link type, classifier type or some other "class type".
 
 Drivers
 -------
 
  - Ethernet high-speed NICs:
    - Add a new driver for Marvell's Octeon PCI Endpoint NIC VF.
    - Intel (100G, ice, idpf):
      - support E825-C devices
    - nVidia/Mellanox:
      - support devices with one port and multiple PCIe links
    - Broadcom (bnxt):
      - support n-tuple filters
      - support configuring the RSS key
    - Wangxun (ngbe/txgbe):
      - implement irq_domain for TXGBE's sub-interrupts
    - Pensando/AMD:
      - support XDP
      - optimize queue submission and wakeup handling (+17% bps)
      - optimize struct layout, saving 28% of memory on queues
 
  - Ethernet NICs embedded and virtual:
    - Google cloud vNIC:
      - refactor driver to perform memory allocations for new queue
        config before stopping and freeing the old queue memory
    - Synopsys (stmmac):
      - obey queueMaxSDU and implement counters required by 802.1Qbv
    - Renesas (ravb):
      - support packet checksum offload
      - suspend to RAM and runtime PM support
 
  - Ethernet switches:
    - nVidia/Mellanox:
      - support for nexthop group statistics
    - Microchip:
      - ksz8: implement PHY loopback
      - add support for KSZ8567, a 7-port 10/100Mbps switch
 
  - PTP:
    - New driver for RENESAS FemtoClock3 Wireless clock generator.
    - Support OCP PTP cards designed and built by Adva.
 
  - CAN:
    - Support recvmsg() flags for own, local and remote traffic
      on CAN BCM sockets.
    - Support for esd GmbH PCIe/402 CAN device family.
    - m_can:
      - Rx/Tx submission coalescing
      - wake on frame Rx
 
  - WiFi:
    - Intel (iwlwifi):
      - enable signaling and payload protected A-MSDUs
      - support wider-bandwidth OFDMA
      - support for new devices
      - bump FW API to 89 for AX devices; 90 for BZ/SC devices
    - MediaTek (mt76):
      - mt7915: newer ADIE version support
      - mt7925: radio temperature sensor support
    - Qualcomm (ath11k):
      - support 6 GHz station power modes: Low Power Indoor (LPI),
        Standard Power) SP and Very Low Power (VLP)
      - QCA6390 & WCN6855: support 2 concurrent station interfaces
      - QCA2066 support
    - Qualcomm (ath12k):
      - refactoring in preparation for Multi-Link Operation (MLO) support
      - 1024 Block Ack window size support
      - firmware-2.bin support
      - support having multiple identical PCI devices (firmware needs to
        have ATH12K_FW_FEATURE_MULTI_QRTR_ID)
      - QCN9274: support split-PHY devices
      - WCN7850: enable Power Save Mode in station mode
      - WCN7850: P2P support
    - RealTek:
      - rtw88: support for more rtw8811cu and rtw8821cu devices
      - rtw89: support SCAN_RANDOM_SN and SET_SCAN_DWELL
      - rtlwifi: speed up USB firmware initialization
      - rtwl8xxxu:
        - RTL8188F: concurrent interface support
        - Channel Switch Announcement (CSA) support in AP mode
    - Broadcom (brcmfmac):
      - per-vendor feature support
      - per-vendor SAE password setup
      - DMI nvram filename quirk for ACEPC W5 Pro
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE6jPA+I1ugmIBA4hXMUZtbf5SIrsFAmXv0mgACgkQMUZtbf5S
 IrtgMxAAuRd+WJW++SENr4KxIWhYO1q6Xcxnai43wrNkan9swD24icG8TYALt4f3
 yoT6idQvWReAb5JNlh9rUQz8R7E0nJXlvEFn5MtJwcthx2C6wFo/XkJlddlRrT+j
 c2xGILwLjRhW65LaC0MZ2ECbEERkFz8xcGfK2SWzUgh6KYvPjcRfKFxugpM7xOQK
 P/Wnqhs4fVRS/Mj/bCcXcO+yhwC121Q3qVeQVjGS0AzEC65hAW87a/kc2BfgcegD
 EyI9R7mf6criQwX+0awubjfoIdr4oW/8oDVNvUDczkJkbaEVaLMQk9P5x/0XnnVS
 UHUchWXyI80Q8Rj12uN1/I0h3WtwNQnCRBuLSmtm6GLfCAwbLvp2nGWDnaXiqryW
 DVKUIHGvqPKjkOOMOVfSvfB3LvkS3xsFVVYiQBQCn0YSs/gtu4CoF2Nty9CiLPbK
 tTuxUnLdPDZDxU//l0VArZmP8p2JM7XQGJ+JH8GFH4SBTyBR23e0iyPSoyaxjnYn
 RReDnHMVsrS1i7GPhbqDJWn+uqMSs7N149i0XmmyeqwQHUVSJN3J2BApP2nCaDfy
 H2lTuYly5FfEezt61NvCE4qr/VsWeEjm1fYlFQ9dFn4pGn+HghyCpw+xD1ZN56DN
 lujemau5B3kk1UTtAT4ypPqvuqjkRFqpNV2LzsJSk/Js+hApw8Y=
 =oY52
 -----END PGP SIGNATURE-----

Merge tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Large effort by Eric to lower rtnl_lock pressure and remove locks:

      - Make commonly used parts of rtnetlink (address, route dumps
        etc) lockless, protected by RCU instead of rtnl_lock.

      - Add a netns exit callback which already holds rtnl_lock,
        allowing netns exit to take rtnl_lock once in the core instead
        of once for each driver / callback.

      - Remove locks / serialization in the socket diag interface.

      - Remove 6 calls to synchronize_rcu() while holding rtnl_lock.

      - Remove the dev_base_lock, depend on RCU where necessary.

   - Support busy polling on a per-epoll context basis. Poll length and
     budget parameters can be set independently of system defaults.

   - Introduce struct net_hotdata, to make sure read-mostly global
     config variables fit in as few cache lines as possible.

   - Add optional per-nexthop statistics to ease monitoring / debug of
     ECMP imbalance problems.

   - Support TCP_NOTSENT_LOWAT in MPTCP.

   - Ensure that IPv6 temporary addresses' preferred lifetimes are long
     enough, compared to other configured lifetimes, and at least 2 sec.

   - Support forwarding of ICMP Error messages in IPSec, per RFC 4301.

   - Add support for the independent control state machine for bonding
     per IEEE 802.1AX-2008 5.4.15 in addition to the existing coupled
     control state machine.

   - Add "network ID" to MCTP socket APIs to support hosts with multiple
     disjoint MCTP networks.

   - Re-use the mono_delivery_time skbuff bit for packets which user
     space wants to be sent at a specified time. Maintain the timing
     information while traversing veth links, bridge etc.

   - Take advantage of MSG_SPLICE_PAGES for RxRPC DATA and ACK packets.

   - Simplify many places iterating over netdevs by using an xarray
     instead of a hash table walk (hash table remains in place, for use
     on fastpaths).

   - Speed up scanning for expired routes by keeping a dedicated list.

   - Speed up "generic" XDP by trying harder to avoid large allocations.

   - Support attaching arbitrary metadata to netconsole messages.

  Things we sprinkled into general kernel code:

   - Enforce VM_IOREMAP flag and range in ioremap_page_range and
     introduce VM_SPARSE kind and vm_area_[un]map_pages (used by
     bpf_arena).

   - Rework selftest harness to enable the use of the full range of ksft
     exit code (pass, fail, skip, xfail, xpass).

  Netfilter:

   - Allow userspace to define a table that is exclusively owned by a
     daemon (via netlink socket aliveness) without auto-removing this
     table when the userspace program exits. Such table gets marked as
     orphaned and a restarting management daemon can re-attach/regain
     ownership.

   - Speed up element insertions to nftables' concatenated-ranges set
     type. Compact a few related data structures.

  BPF:

   - Add BPF token support for delegating a subset of BPF subsystem
     functionality from privileged system-wide daemons such as systemd
     through special mount options for userns-bound BPF fs to a trusted
     & unprivileged application.

   - Introduce bpf_arena which is sparse shared memory region between
     BPF program and user space where structures inside the arena can
     have pointers to other areas of the arena, and pointers work
     seamlessly for both user-space programs and BPF programs.

   - Introduce may_goto instruction that is a contract between the
     verifier and the program. The verifier allows the program to loop
     assuming it's behaving well, but reserves the right to terminate
     it.

   - Extend the BPF verifier to enable static subprog calls in spin lock
     critical sections.

   - Support registration of struct_ops types from modules which helps
     projects like fuse-bpf that seeks to implement a new struct_ops
     type.

   - Add support for retrieval of cookies for perf/kprobe multi links.

   - Support arbitrary TCP SYN cookie generation / validation in the TC
     layer with BPF to allow creating SYN flood handling in BPF
     firewalls.

   - Add code generation to inline the bpf_kptr_xchg() helper which
     improves performance when stashing/popping the allocated BPF
     objects.

  Wireless:

   - Add SPP (signaling and payload protected) AMSDU support.

   - Support wider bandwidth OFDMA, as required for EHT operation.

  Driver API:

   - Major overhaul of the Energy Efficient Ethernet internals to
     support new link modes (2.5GE, 5GE), share more code between
     drivers (especially those using phylib), and encourage more
     uniform behavior. Convert and clean up drivers.

   - Define an API for querying per netdev queue statistics from
     drivers.

   - IPSec: account in global stats for fully offloaded sessions.

   - Create a concept of Ethernet PHY Packages at the Device Tree level,
     to allow parameterizing the existing PHY package code.

   - Enable Rx hashing (RSS) on GTP protocol fields.

  Misc:

   - Improvements and refactoring all over networking selftests.

   - Create uniform module aliases for TC classifiers, actions, and
     packet schedulers to simplify creating modprobe policies.

   - Address all missing MODULE_DESCRIPTION() warnings in networking.

   - Extend the Netlink descriptions in YAML to cover message
     encapsulation or "Netlink polymorphism", where interpretation of
     nested attributes depends on link type, classifier type or some
     other "class type".

  Drivers:

   - Ethernet high-speed NICs:
      - Add a new driver for Marvell's Octeon PCI Endpoint NIC VF.
      - Intel (100G, ice, idpf):
         - support E825-C devices
      - nVidia/Mellanox:
         - support devices with one port and multiple PCIe links
      - Broadcom (bnxt):
         - support n-tuple filters
         - support configuring the RSS key
      - Wangxun (ngbe/txgbe):
         - implement irq_domain for TXGBE's sub-interrupts
      - Pensando/AMD:
         - support XDP
         - optimize queue submission and wakeup handling (+17% bps)
         - optimize struct layout, saving 28% of memory on queues

   - Ethernet NICs embedded and virtual:
      - Google cloud vNIC:
         - refactor driver to perform memory allocations for new queue
           config before stopping and freeing the old queue memory
      - Synopsys (stmmac):
         - obey queueMaxSDU and implement counters required by 802.1Qbv
      - Renesas (ravb):
         - support packet checksum offload
         - suspend to RAM and runtime PM support

   - Ethernet switches:
      - nVidia/Mellanox:
         - support for nexthop group statistics
      - Microchip:
         - ksz8: implement PHY loopback
         - add support for KSZ8567, a 7-port 10/100Mbps switch

   - PTP:
      - New driver for RENESAS FemtoClock3 Wireless clock generator.
      - Support OCP PTP cards designed and built by Adva.

   - CAN:
      - Support recvmsg() flags for own, local and remote traffic on CAN
        BCM sockets.
      - Support for esd GmbH PCIe/402 CAN device family.
      - m_can:
         - Rx/Tx submission coalescing
         - wake on frame Rx

   - WiFi:
      - Intel (iwlwifi):
         - enable signaling and payload protected A-MSDUs
         - support wider-bandwidth OFDMA
         - support for new devices
         - bump FW API to 89 for AX devices; 90 for BZ/SC devices
      - MediaTek (mt76):
         - mt7915: newer ADIE version support
         - mt7925: radio temperature sensor support
      - Qualcomm (ath11k):
         - support 6 GHz station power modes: Low Power Indoor (LPI),
           Standard Power) SP and Very Low Power (VLP)
         - QCA6390 & WCN6855: support 2 concurrent station interfaces
         - QCA2066 support
      - Qualcomm (ath12k):
         - refactoring in preparation for Multi-Link Operation (MLO)
           support
         - 1024 Block Ack window size support
         - firmware-2.bin support
         - support having multiple identical PCI devices (firmware needs
           to have ATH12K_FW_FEATURE_MULTI_QRTR_ID)
         - QCN9274: support split-PHY devices
         - WCN7850: enable Power Save Mode in station mode
         - WCN7850: P2P support
      - RealTek:
         - rtw88: support for more rtw8811cu and rtw8821cu devices
         - rtw89: support SCAN_RANDOM_SN and SET_SCAN_DWELL
         - rtlwifi: speed up USB firmware initialization
         - rtwl8xxxu:
             - RTL8188F: concurrent interface support
             - Channel Switch Announcement (CSA) support in AP mode
      - Broadcom (brcmfmac):
         - per-vendor feature support
         - per-vendor SAE password setup
         - DMI nvram filename quirk for ACEPC W5 Pro"

* tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2255 commits)
  nexthop: Fix splat with CONFIG_DEBUG_PREEMPT=y
  nexthop: Fix out-of-bounds access during attribute validation
  nexthop: Only parse NHA_OP_FLAGS for dump messages that require it
  nexthop: Only parse NHA_OP_FLAGS for get messages that require it
  bpf: move sleepable flag from bpf_prog_aux to bpf_prog
  bpf: hardcode BPF_PROG_PACK_SIZE to 2MB * num_possible_nodes()
  selftests/bpf: Add kprobe multi triggering benchmarks
  ptp: Move from simple ida to xarray
  vxlan: Remove generic .ndo_get_stats64
  vxlan: Do not alloc tstats manually
  devlink: Add comments to use netlink gen tool
  nfp: flower: handle acti_netdevs allocation failure
  net/packet: Add getsockopt support for PACKET_COPY_THRESH
  net/netlink: Add getsockopt support for NETLINK_LISTEN_ALL_NSID
  selftests/bpf: Add bpf_arena_htab test.
  selftests/bpf: Add bpf_arena_list test.
  selftests/bpf: Add unit tests for bpf_arena_alloc/free_pages
  bpf: Add helper macro bpf_addr_space_cast()
  libbpf: Recognize __arena global variables.
  bpftool: Recognize arena map type
  ...
2024-03-12 17:44:08 -07:00
Linus Torvalds
ff887eb07c workqueue: Changes for v6.9
This cycle, a lot of workqueue changes including some that are significant
 and invasive.
 
 - During v6.6 cycle, unbound workqueues were updated so that they are more
   topology aware and flexible, which among other things improved workqueue
   behavior on modern multi-L3 CPUs. In the process, 636b927eba
   ("workqueue: Make unbound workqueues to use per-cpu pool_workqueues")
   switched unbound workqueues to use per-CPU frontend pool_workqueues as a
   part of increasing front-back mapping flexibility.
 
   An unwelcome side effect of this change was that this made max concurrency
   enforcement per-CPU blowing up the maximum number of allowed concurrent
   executions. I incorrectly assumed that this wouldn't cause practical
   problems as most unbound workqueue users are self-regulate max
   concurrency; however, there definitely are which don't (e.g. on IO paths)
   and the drastic increase in the allowed max concurrency led to noticeable
   perf regressions in some use cases.
 
   This is now addressed by separating out max concurrency enforcement to a
   separate struct - wq_node_nr_active - which makes @max_active consistently
   mean system-wide max concurrency regardless of the number of CPUs or
   (finally) NUMA nodes. This is a rather invasive and, in places, a bit
   clunky; however, the clunkiness rises from the the inherent requirement to
   handle the disagreement between the execution locality domain and max
   concurrency enforcement domain on some modern machines. See 5797b1c189
   ("workqueue: Implement system-wide nr_active enforcement for unbound
   workqueues") for more details.
 
 - BH workqueue support is added. They are similar to per-CPU workqueues but
   execute work items in the softirq context. This is expected to replace
   tasklet. However, currently, it's missing the ability to disable and
   enable work items which is needed to convert many tasklet users. To avoid
   crowding this merge window too much, this will be included in the next
   merge window. A separate pull request will be sent for the couple
   conversion patches that are currently pending.
 
 - Waiman plugged a long-standing hole in workqueue CPU isolation where
   ordered workqueues didn't follow wq_unbound_cpumask updates. Ordered
   workqueues now follow the same rules as other unbound workqueues.
 
 - More CPU isolation improvements: Juri fixed another deficit in workqueue
   isolation where unbound rescuers don't respect wq_unbound_cpumask.
   Leonardo fixed delayed_work timers firing on isolated CPUs.
 
 - Other misc changes.
 -----BEGIN PGP SIGNATURE-----
 
 iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCZe7JCQ4cdGpAa2VybmVs
 Lm9yZwAKCRCxYfJx3gVYGcnqAP9UP8zEM1la19cilhboDumxmRWyRpV/egFOqsMP
 Y5PuoAEAtsBJtQWtm5w46+y+fk3nK2ugXlQio2gH0qQcxX6SdgQ=
 =/ovv
 -----END PGP SIGNATURE-----

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

Pull workqueue updates from Tejun Heo:
 "This cycle, a lot of workqueue changes including some that are
  significant and invasive.

   - During v6.6 cycle, unbound workqueues were updated so that they are
     more topology aware and flexible, which among other things improved
     workqueue behavior on modern multi-L3 CPUs. In the process, commit
     636b927eba ("workqueue: Make unbound workqueues to use per-cpu
     pool_workqueues") switched unbound workqueues to use per-CPU
     frontend pool_workqueues as a part of increasing front-back mapping
     flexibility.

     An unwelcome side effect of this change was that this made max
     concurrency enforcement per-CPU blowing up the maximum number of
     allowed concurrent executions. I incorrectly assumed that this
     wouldn't cause practical problems as most unbound workqueue users
     are self-regulate max concurrency; however, there definitely are
     which don't (e.g. on IO paths) and the drastic increase in the
     allowed max concurrency led to noticeable perf regressions in some
     use cases.

     This is now addressed by separating out max concurrency enforcement
     to a separate struct - wq_node_nr_active - which makes @max_active
     consistently mean system-wide max concurrency regardless of the
     number of CPUs or (finally) NUMA nodes. This is a rather invasive
     and, in places, a bit clunky; however, the clunkiness rises from
     the the inherent requirement to handle the disagreement between the
     execution locality domain and max concurrency enforcement domain on
     some modern machines.

     See commit 5797b1c189 ("workqueue: Implement system-wide
     nr_active enforcement for unbound workqueues") for more details.

   - BH workqueue support is added.

     They are similar to per-CPU workqueues but execute work items in
     the softirq context. This is expected to replace tasklet. However,
     currently, it's missing the ability to disable and enable work
     items which is needed to convert many tasklet users. To avoid
     crowding this merge window too much, this will be included in the
     next merge window. A separate pull request will be sent for the
     couple conversion patches that are currently pending.

   - Waiman plugged a long-standing hole in workqueue CPU isolation
     where ordered workqueues didn't follow wq_unbound_cpumask updates.
     Ordered workqueues now follow the same rules as other unbound
     workqueues.

   - More CPU isolation improvements: Juri fixed another deficit in
     workqueue isolation where unbound rescuers don't respect
     wq_unbound_cpumask. Leonardo fixed delayed_work timers firing on
     isolated CPUs.

   - Other misc changes"

* tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (54 commits)
  workqueue: Drain BH work items on hot-unplugged CPUs
  workqueue: Introduce from_work() helper for cleaner callback declarations
  workqueue: Control intensive warning threshold through cmdline
  workqueue: Make @flags handling consistent across set_work_data() and friends
  workqueue: Remove clear_work_data()
  workqueue: Factor out work_grab_pending() from __cancel_work_sync()
  workqueue: Clean up enum work_bits and related constants
  workqueue: Introduce work_cancel_flags
  workqueue: Use variable name irq_flags for saving local irq flags
  workqueue: Reorganize flush and cancel[_sync] functions
  workqueue: Rename __cancel_work_timer() to __cancel_timer_sync()
  workqueue: Use rcu_read_lock_any_held() instead of rcu_read_lock_held()
  workqueue: Cosmetic changes
  workqueue, irq_work: Build fix for !CONFIG_IRQ_WORK
  workqueue: Fix queue_work_on() with BH workqueues
  async: Use a dedicated unbound workqueue with raised min_active
  workqueue: Implement workqueue_set_min_active()
  workqueue: Fix kernel-doc comment of unplug_oldest_pwq()
  workqueue: Bind unbound workqueue rescuer to wq_unbound_cpumask
  kernel/workqueue: Let rescuers follow unbound wq cpumask changes
  ...
2024-03-11 12:50:42 -07:00
Masahiro Yamada
e2bad142bb kbuild: unexport abs_srctree and abs_objtree
Commit 25b146c5b8 ("kbuild: allow Kbuild to start from any directory")
exported abs_srctree and abs_objtree to avoid recomputation after the
sub-make. However, this approach turned out to be fragile.

Commit 5fa94ceb79 ("kbuild: set correct abs_srctree and abs_objtree
for package builds") moved them above "ifneq ($(sub_make_done),1)",
eliminating the need for exporting them.

These are only needed in the top Makefile. If an absolute path is
required in sub-directories, you can use $(abspath ) or $(realpath )
as needed.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-03-10 17:27:17 +09:00
Miguel Ojeda
768409cff6 rust: upgrade to Rust 1.76.0
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0
(i.e. the latest) [1].

See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").

# Unstable features

No unstable features that we use were stabilized in Rust 1.76.0.

The only unstable features allowed to be used outside the `kernel` crate
are still `new_uninit,offset_of`, though other code to be upstreamed
may increase the list.

Please see [3] for details.

# Required changes

`rustc` (and others) now warns when it cannot connect to the Make
jobserver, thus mark those invocations as recursive as needed. Please
see the previous commit for details.

# Other changes

Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore
for DWARFv4 [4][5]. For instance, in the uncompressed debug info case,
this debug information took:

    samples/rust/rust_minimal.o   ~64 KiB (~18% of total object size)
    rust/kernel.o                 ~92 KiB (~15%)
    rust/core.o                  ~114 KiB ( ~5%)

In the compressed debug info (zlib) case:

    samples/rust/rust_minimal.o   ~11 KiB (~6%)
    rust/kernel.o                 ~17 KiB (~5%)
    rust/core.o                   ~21 KiB (~1.5%)

In addition, the `rustc_codegen_gcc` backend now does not emit the
`.eh_frame` section when compiling under `-Cpanic=abort` [6], thus
removing the need for the patch in the CI to compile the kernel [7].
Moreover, it also now emits the `.comment` section too [6].

# `alloc` upgrade and reviewing

The vast majority of changes are due to our `alloc` fork being upgraded
at once.

There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.

Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.

Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.

To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:

    # Get the difference with respect to the old version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > old.patch
    git -C linux restore rust/alloc

    # Apply this patch.
    git -C linux am rust-upgrade.patch

    # Get the difference with respect to the new version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > new.patch
    git -C linux restore rust/alloc

Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.

Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
Link: https://github.com/rust-lang/compiler-team/issues/688 [4]
Link: https://github.com/rust-lang/rust/pull/117962 [5]
Link: https://github.com/rust-lang/rust/pull/118068 [6]
Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7]
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-29 22:18:05 +01:00
Miguel Ojeda
ecab4115c4 kbuild: mark rustc (and others) invocations as recursive
`rustc` (like Cargo) may take advantage of the jobserver at any time
(e.g. for backend parallelism, or eventually frontend too). In the kernel,
we call `rustc` with `-Ccodegen-units=1` (and `-Zthreads` is 1 so far),
so we do not expect parallelism. However, in the upcoming Rust 1.76.0, a
warning is emitted by `rustc` [1] when it cannot connect to the jobserver
it was passed (in many cases, but not all: compiling and `--print sysroot`
do, but `--version` does not). And given GNU Make always passes
the jobserver in the environment variable (even when a line is deemed
non-recursive), `rustc` will end up complaining about it (in particular
in Make 4.3 where there is only the simple pipe jobserver style).

One solution is to remove the jobserver from `MAKEFLAGS`. However, we
can mark the lines with calls to `rustc` (and Cargo) as recursive, which
looks simpler. This is being documented as a recommendation in `rustc`
[2] and allows us to be ready for the time we may use parallelism inside
`rustc` (potentially now, if a user passes `-Zthreads`). Thus do so.

Similarly, do the same for `rustdoc` and `cargo` calls.

Finally, there is one case that the solution does not cover, which is the
`$(shell ...)` call we have. Thus, for that one, set an empty `MAKEFLAGS`
environment variable.

Link: https://github.com/rust-lang/rust/issues/120515 [1]
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://github.com/rust-lang/rust/pull/121564 [2]
Link: https://lore.kernel.org/r/20240217002638.57373-1-ojeda@kernel.org
[ Reworded to add link to PR documenting the recommendation. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-29 22:16:38 +01:00