linux-stable.git/arch/powerpc/include, branch v6.12.2

KVM: PPC: Book3S HV: Fix kmv -> kvm typo

2024-12-05T13:02:14+00:00

[ Upstream commit 590d2f9347f7974d7954400e5d937672fd844a8b ]

Fix typo in the following kvm function names from:

 kmvhv_counters_tracepoint_regfunc -> kvmhv_counters_tracepoint_regfunc
 kmvhv_counters_tracepoint_unregfunc -> kvmhv_counters_tracepoint_unregfunc

Fixes: e1f288d2f9c6 ("KVM: PPC: Book3S HV nestedv2: Add support for reading VPA counters for pseries guests")
Reported-by: Madhavan Srinivasan 
Reviewed-by: Ritesh Harjani (IBM) 
Reviewed-by: Amit Machhiwal 
Signed-off-by: Kajol Jain 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/20241114085020.1147912-1-kjain@linux.ibm.com
Signed-off-by: Sasha Levin

powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static

2024-12-05T13:02:14+00:00

[ Upstream commit a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ]

These functions are not used outside of sstep.c

Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de
Signed-off-by: Sasha Levin

powerpc/fadump: allocate memory for additional parameters early

2024-12-05T13:02:11+00:00

[ Upstream commit f4892c68ecc1cf45e41a78820dd2eebccc945b66 ]

Memory for passing additional parameters to fadump capture kernel
is allocated during subsys_initcall level, using memblock. But
as slab is already available by this time, allocation happens via
the buddy allocator. This may work for radix MMU but is likely to
fail in most cases for hash MMU as hash MMU needs this memory in
the first memory block for it to be accessible in real mode in the
capture kernel (second boot). So, allocate memory for additional
parameters area as soon as MMU mode is obvious.

Fixes: 683eab94da75 ("powerpc/fadump: setup additional parameters for dump capture kernel")
Reported-by: Venkat Rao Bagalkote 
Closes: https://lore.kernel.org/lkml/a70e4064-a040-447b-8556-1fd02f19383d@linux.vnet.ibm.com/T/#u
Signed-off-by: Hari Bathini 
Signed-off-by: Sourabh Jain 
Tested-by: Venkat Rao Bagalkote 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/20241107055817.489795-1-sourabhjain@linux.ibm.com
Signed-off-by: Sasha Levin

powerpc/pseries: Fix dtl_access_lock to be a rw_semaphore

2024-12-05T13:02:06+00:00

[ Upstream commit cadae3a45d23aa4f6485938a67cbc47aaaa25e38 ]

The dtl_access_lock needs to be a rw_sempahore, a sleeping lock, because
the code calls kmalloc() while holding it, which can sleep:

  # echo 1 > /proc/powerpc/vcpudispatch_stats
  BUG: sleeping function called from invalid context at include/linux/sched/mm.h:337
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 199, name: sh
  preempt_count: 1, expected: 0
  3 locks held by sh/199:
   #0: c00000000a0743f8 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x324/0x438
   #1: c0000000028c7058 (dtl_enable_mutex){+.+.}-{3:3}, at: vcpudispatch_stats_write+0xd4/0x5f4
   #2: c0000000028c70b8 (dtl_access_lock){+.+.}-{2:2}, at: vcpudispatch_stats_write+0x220/0x5f4
  CPU: 0 PID: 199 Comm: sh Not tainted 6.10.0-rc4 #152
  Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
  Call Trace:
    dump_stack_lvl+0x130/0x148 (unreliable)
    __might_resched+0x174/0x410
    kmem_cache_alloc_noprof+0x340/0x3d0
    alloc_dtl_buffers+0x124/0x1ac
    vcpudispatch_stats_write+0x2a8/0x5f4
    proc_reg_write+0xf4/0x150
    vfs_write+0xfc/0x438
    ksys_write+0x88/0x148
    system_call_exception+0x1c4/0x5a0
    system_call_common+0xf4/0x258

Fixes: 06220d78f24a ("powerpc/pseries: Introduce rwlock to gatekeep DTLB usage")
Tested-by: Kajol Jain 
Reviewed-by: Nysal Jan K.A 
Reviewed-by: Kajol Jain 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/20240819122401.513203-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin

powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init()

2024-12-05T13:02:04+00:00

[ Upstream commit 05b94cae1c47f94588c3e7096963c1007c4d9c1d ]

During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE,
since pageblock_order is still zero and it gets initialized
later during initmem_init() e.g.
setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order()

One such use case where this causes issue is -
early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init()

This causes CMA memory alignment check to be bypassed in
cma_init_reserved_mem(). Then later cma_activate_area() can hit
a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory
area was not pageblock_order aligned.

Fix it by moving the fadump_cma_init() after initmem_init(),
where other such cma reservations also gets called.


==============
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010
flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA
raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1))
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:778!

Call Trace:
__free_one_page+0x57c/0x7b0 (unreliable)
free_pcppages_bulk+0x1a8/0x2c8
free_unref_page_commit+0x3d4/0x4e4
free_unref_page+0x458/0x6d0
init_cma_reserved_pageblock+0x114/0x198
cma_init_reserved_areas+0x270/0x3e0
do_one_initcall+0x80/0x2f8
kernel_init_freeable+0x33c/0x530
kernel_init+0x34/0x26c
ret_from_kernel_user_thread+0x14/0x1c

Fixes: 11ac3e87ce09 ("mm: cma: use pageblock_order as the single alignment")
Suggested-by: David Hildenbrand 
Reported-by: Sachin P Bappalige 
Acked-by: Hari Bathini 
Reviewed-by: Madhavan Srinivasan 
Signed-off-by: Ritesh Harjani (IBM) 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com
Signed-off-by: Sasha Levin

powerpc/vdso: Flag VDSO64 entry points as functions

2024-12-05T13:02:03+00:00

[ Upstream commit 0161bd38c24312853ed5ae9a425a1c41c4ac674a ]

On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.

$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
  Class:                             ELF64
  Data:                              2's complement, big endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              DYN (Shared object file)
  Machine:                           PowerPC64
  Version:                           0x1
...

Symbol table '.dynsym' contains 12 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
     1: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15
...
     4: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
     5: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15

Symbol table '.symtab' contains 56 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
    45: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
    46: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __kernel_getcpu
    47: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __kernel_clock_getres

To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.

The original commit that brought VDSO support into powerpc/64 has the
following explanation:

    Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
    can't be expected to link against them directly, the vDSO's are both seen
    as if they were linked at 0 and the symbols just contain offsets to the
    various functions.  This is done on purpose to avoid a relocation step
    (ppc64 functions normally have descriptors with abs addresses in them).
    When glibc uses those functions, it's expected to use it's own trampolines
    that know how to reach them.

The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.

glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.

For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.

So lets flag VDSO entry points as functions and revert the
selftest change.

Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805
Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy 
Reviewed-By: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin

Merge tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-09-21T14:29:05+00:00

Pull MM updates from Andrew Morton:
"Along with the usual shower of singleton patches, notable patch series
in this pull request are:

- "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
consistency to the APIs and behaviour of these two core allocation
functions. This also simplifies/enables Rustification.

- "Some cleanups for shmem" from Baolin Wang. No functional changes -
mode code reuse, better function naming, logic simplifications.

- "mm: some small page fault cleanups" from Josef Bacik. No
functional changes - code cleanups only.

- "Various memory tiering fixes" from Zi Yan. A small fix and a
little cleanup.

- "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
simplifications and .text shrinkage.

- "Kernel stack usage histogram" from Pasha Tatashin and Shakeel
Butt. This is a feature, it adds new feilds to /proc/vmstat such as

$ grep kstack /proc/vmstat
kstack_1k 3
kstack_2k 188
kstack_4k 11391
kstack_8k 243
kstack_16k 0

which tells us that 11391 processes used 4k of stack while none at
all used 16k. Useful for some system tuning things, but
partivularly useful for "the dynamic kernel stack project".

- "kmemleak: support for percpu memory leak detect" from Pavel
Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory.

- "mm: memcg: page counters optimizations" from Roman Gushchin. "3
independent small optimizations of page counters".

- "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from
David Hildenbrand. Improves PTE/PMD splitlock detection, makes
powerpc/8xx work correctly by design rather than by accident.

- "mm: remove arch_make_page_accessible()" from David Hildenbrand.
Some folio conversions which make arch_make_page_accessible()
unneeded.

- "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David
Finkel. Cleans up and fixes our handling of the resetting of the
cgroup/process peak-memory-use detector.

- "Make core VMA operations internal and testable" from Lorenzo
Stoakes. Rationalizaion and encapsulation of the VMA manipulation
APIs. With a view to better enable testing of the VMA functions,
even from a userspace-only harness.

- "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix
issues in the zswap global shrinker, resulting in improved
performance.

- "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill
in some missing info in /proc/zoneinfo.

- "mm: replace follow_page() by folio_walk" from David Hildenbrand.
Code cleanups and rationalizations (conversion to folio_walk())
resulting in the removal of follow_page().

- "improving dynamic zswap shrinker protection scheme" from Nhat
Pham. Some tuning to improve zswap's dynamic shrinker. Significant
reductions in swapin and improvements in performance are shown.

- "mm: Fix several issues with unaccepted memory" from Kirill
Shutemov. Improvements to the new unaccepted memory feature,

- "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on
DAX PUDs. This was missing, although nobody seems to have notied
yet.

- "Introduce a store type enum for the Maple tree" from Sidhartha
Kumar. Cleanups and modest performance improvements for the maple
tree library code.

- "memcg: further decouple v1 code from v2" from Shakeel Butt. Move
more cgroup v1 remnants away from the v2 memcg code.

- "memcg: initiate deprecation of v1 features" from Shakeel Butt.
Adds various warnings telling users that memcg v1 features are
deprecated.

- "mm: swap: mTHP swap allocator base on swap cluster order" from
Chris Li. Greatly improves the success rate of the mTHP swap
allocation.

- "mm: introduce numa_memblks" from Mike Rapoport. Moves various
disparate per-arch implementations of numa_memblk code into generic
code.

- "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
improves the performance of munmap() of swap-filled ptes.

- "support large folio swap-out and swap-in for shmem" from Baolin
Wang. With this series we no longer split shmem large folios into
simgle-page folios when swapping out shmem.

- "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice
performance improvements and code reductions for gigantic folios.

- "support shmem mTHP collapse" from Baolin Wang. Adds support for
khugepaged's collapsing of shmem mTHP folios.

- "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
performance regression due to the addition of mseal().

- "Increase the number of bits available in page_type" from Matthew
Wilcox. Increases the number of bits available in page_type!

- "Simplify the page flags a little" from Matthew Wilcox. Many legacy
page flags are now folio flags, so the page-based flags and their
accessors/mutators can be removed.

- "mm: store zero pages to be swapped out in a bitmap" from Usama
Arif. An optimization which permits us to avoid writing/reading
zero-filled zswap pages to backing store.

- "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race
window which occurs when a MAP_FIXED operqtion is occurring during
an unrelated vma tree walk.

- "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of
the vma_merge() functionality, making ot cleaner, more testable and
better tested.

- "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.
Minor fixups of DAMON selftests and kunit tests.

- "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.
Code cleanups and folio conversions.

- "Shmem mTHP controls and stats improvements" from Ryan Roberts.
Cleanups for shmem controls and stats.

- "mm: count the number of anonymous THPs per size" from Barry Song.
Expose additional anon THP stats to userspace for improved tuning.

- "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more
folio conversions and removal of now-unused page-based APIs.

- "replace per-quota region priorities histogram buffer with
per-context one" from SeongJae Park. DAMON histogram
rationalization.

- "Docs/damon: update GitHub repo URLs and maintainer-profile" from
SeongJae Park. DAMON documentation updates.

- "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and
improve related doc and warn" from Jason Wang: fixes usage of page
allocator __GFP_NOFAIL and GFP_ATOMIC flags.

- "mm: split underused THPs" from Yu Zhao. Improve THP=always policy.
This was overprovisioning THPs in sparsely accessed memory areas.

- "zram: introduce custom comp backends API" frm Sergey Senozhatsky.
Add support for zram run-time compression algorithm tuning.

- "mm: Care about shadow stack guard gap when getting an unmapped
area" from Mark Brown. Fix up the various arch_get_unmapped_area()
implementations to better respect guard areas.

- "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability
of mem_cgroup_iter() and various code cleanups.

- "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
pfnmap support.

- "resource: Fix region_intersects() vs add_memory_driver_managed()"
from Huang Ying. Fix a bug in region_intersects() for systems with
CXL memory.

- "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches
a couple more code paths to correctly recover from the encountering
of poisoned memry.

- "mm: enable large folios swap-in support" from Barry Song. Support
the swapin of mTHP memory into appropriately-sized folios, rather
than into single-page folios"

* tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits)
zram: free secondary algorithms names
uprobes: turn xol_area->pages[2] into xol_area->page
uprobes: introduce the global struct vm_special_mapping xol_mapping
Revert "uprobes: use vm_special_mapping close() functionality"
mm: support large folios swap-in for sync io devices
mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios
mm: fix swap_read_folio_zeromap() for large folios with partial zeromap
mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries
set_memory: add __must_check to generic stubs
mm/vma: return the exact errno in vms_gather_munmap_vmas()
memcg: cleanup with !CONFIG_MEMCG_V1
mm/show_mem.c: report alloc tags in human readable units
mm: support poison recovery from copy_present_page()
mm: support poison recovery from do_cow_fault()
resource, kunit: add test case for region_intersects()
resource: make alloc_free_mem_region() works for iomem_resource
mm: z3fold: deprecate CONFIG_Z3FOLD
vfio/pci: implement huge_fault support
mm/arm64: support large pfn mappings
mm/x86: support large pfn mappings
...

Merge tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2024-09-19T06:03:00+00:00

Pull powerpc updates from Michael Ellerman:

 - Reduce alignment constraints on STRICT_KERNEL_RWX and speed-up TLB
   misses on 8xx and 603

 - Replace kretprobe code with rethook and enable fprobe

 - Remove the "fast endian switch" syscall

 - Handle DLPAR device tree updates in kernel, allowing the deprecation
   of the binary /proc/powerpc/ofdt interface

Thanks to Abhishek Dubey, Alex Shi, Benjamin Gray, Christophe Leroy,
Gaosheng Cui, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari
Bathini, Huang Xiaojia, Jinjie Ruan, Madhavan Srinivasan, Miguel Ojeda,
Mina Almasry, Narayana Murty N, Naveen Rao, Rob Herring (Arm), Scott
Cheloha, Segher Boessenkool, Stephen Rothwell, Thomas Zimmermann, Uwe
Kleine-König, Vaibhav Jain, and Zhang Zekun.

* tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (59 commits)
  powerpc/atomic: Use YZ constraints for DS-form instructions
  MAINTAINERS: powerpc: Add Maddy
  powerpc: Switch back to struct platform_driver::remove()
  powerpc/pseries/eeh: Fix pseries_eeh_err_inject
  selftests/powerpc: Allow building without static libc
  macintosh/via-pmu: register_pmu_pm_ops() can be __init
  powerpc: Stop using no_llseek
  powerpc/64s: Remove the "fast endian switch" syscall
  powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages
  powerpc/mm/64s: Move THP reqs into a separate symbol
  powerpc/64s: Make mmu_hash_ops __ro_after_init
  powerpc: Replace kretprobe code with rethook on powerpc
  powerpc: pseries: Constify struct kobj_type
  powerpc: powernv: Constify struct kobj_type
  powerpc: Constify struct kobj_type
  powerpc/pseries/dlpar: Add device tree nodes for DLPAR IO add
  powerpc/pseries/dlpar: Remove device tree node for DLPAR IO remove
  powerpc/pseries: Use correct data types from pseries_hp_errorlog struct
  powerpc/vdso: Inconditionally use CFUNC macro
  powerpc/32: Implement validation of emergency stack
  ...

Merge tag 'random-6.12-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

2024-09-18T13:26:31+00:00

Pull random number generator updates from Jason Donenfeld:
 "Originally I'd planned on sending each of the vDSO getrandom()
  architecture ports to their respective arch trees. But as we started
  to work on this, we found lots of interesting issues in the shared
  code and infrastructure, the fixes for which the various archs needed
  to base their work.

  So in the end, this turned into a nice collaborative effort fixing up
  issues and porting to 5 new architectures -- arm64, powerpc64,
  powerpc32, s390x, and loongarch64 -- with everybody pitching in and
  commenting on each other's code. It was a fun development cycle.

  This contains:

   - Numerous fixups to the vDSO selftest infrastructure, getting it
     running successfully on more platforms, and fixing bugs in it.

   - Additions to the vDSO getrandom & chacha selftests. Basically every
     time manual review unearthed a bug in a revision of an arch patch,
     or an ambiguity, the tests were augmented.

     By the time the last arch was submitted for review, s390x, v1 of
     the series was essentially fine right out of the gate.

   - Fixes to the the generic C implementation of vDSO getrandom, to
     build and run successfully on all archs, decoupling it from
     assumptions we had (unintentionally) made on x86_64 that didn't
     carry through to the other architectures.

   - Port of vDSO getrandom to LoongArch64, from Xi Ruoyao and acked by
     Huacai Chen.

   - Port of vDSO getrandom to ARM64, from Adhemerval Zanella and acked
     by Will Deacon.

   - Port of vDSO getrandom to PowerPC, in both 32-bit and 64-bit
     varieties, from Christophe Leroy and acked by Michael Ellerman.

   - Port of vDSO getrandom to S390X from Heiko Carstens, the arch
     maintainer.

  While it'd be natural for there to be things to fix up over the course
  of the development cycle, these patches got a decent amount of review
  from a fairly diverse crew of folks on the mailing lists, and, for the
  most part, they've been cooking in linux-next, which has been helpful
  for ironing out build issues.

  In terms of architectures, I think that mostly takes care of the
  important 64-bit archs with hardware still being produced and running
  production loads in settings where vDSO getrandom is likely to help.

  Arguably there's still RISC-V left, and we'll see for 6.13 whether
  they find it useful and submit a port"

* tag 'random-6.12-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (47 commits)
  selftests: vDSO: check cpu caps before running chacha test
  s390/vdso: Wire up getrandom() vdso implementation
  s390/vdso: Move vdso symbol handling to separate header file
  s390/vdso: Allow alternatives in vdso code
  s390/module: Provide find_section() helper
  s390/facility: Let test_facility() generate static branch if possible
  s390/alternatives: Remove ALT_FACILITY_EARLY
  s390/facility: Disable compile time optimization for decompressor code
  selftests: vDSO: fix vdso_config for s390
  selftests: vDSO: fix ELF hash table entry size for s390x
  powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO64
  powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO32
  powerpc/vdso: Refactor CFLAGS for CVDSO build
  powerpc/vdso32: Add crtsavres
  mm: Define VM_DROPPABLE for powerpc/32
  powerpc/vdso: Fix VDSO data access when running in a non-root time namespace
  selftests: vDSO: don't include generated headers for chacha test
  arm64: vDSO: Wire up getrandom() vDSO implementation
  arm64: alternative: make alternative_has_cap_likely() VDSO compatible
  selftests: vDSO: also test counter in vdso_test_chacha
  ...

Merge tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux

2024-09-18T05:52:24+00:00

Pull RCU updates from Neeraj Upadhyay:
 "Context tracking:
   - rename context tracking state related symbols and remove references
     to "dynticks" in various context tracking state variables and
     related helpers
   - force context_tracking_enabled_this_cpu() to be inlined to avoid
     leaving a noinstr section

  CSD lock:
   - enhance CSD-lock diagnostic reports
   - add an API to provide an indication of ongoing CSD-lock stall

  nocb:
   - update and simplify RCU nocb code to handle (de-)offloading of
     callbacks only for offline CPUs
   - fix RT throttling hrtimer being armed from offline CPU

  rcutorture:
   - remove redundant rcu_torture_ops get_gp_completed fields
   - add SRCU ->same_gp_state and ->get_comp_state functions
   - add generic test for NUM_ACTIVE_*RCU_POLL* for testing RCU and SRCU
     polled grace periods
   - add CFcommon.arch for arch-specific Kconfig options
   - print number of update types in rcu_torture_write_types()
   - add rcutree.nohz_full_patience_delay testing to the TREE07 scenario
   - add a stall_cpu_repeat module parameter to test repeated CPU stalls
   - add argument to limit number of CPUs a guest OS can use in
     torture.sh

  rcustall:
   - abbreviate RCU CPU stall warnings during CSD-lock stalls
   - Allow dump_cpu_task() to be called without disabling preemption
   - defer printing stall-warning backtrace when holding rcu_node lock

  srcu:
   - make SRCU gp seq wrap-around faster
   - add KCSAN checks for concurrent updates to ->srcu_n_exp_nodelay and
     ->reschedule_count which are used in heuristics governing
     auto-expediting of normal SRCU grace periods and
     grace-period-state-machine delays
   - mark idle SRCU-barrier callbacks to help identify stuck
     SRCU-barrier callback

  rcu tasks:
   - remove RCU Tasks Rude asynchronous APIs as they are no longer used
   - stop testing RCU Tasks Rude asynchronous APIs
   - fix access to non-existent percpu regions
   - check processor-ID assumptions during chosen CPU calculation for
     callback enqueuing
   - update description of rtp->tasks_gp_seq grace-period sequence
     number
   - add rcu_barrier_cb_is_done() to identify whether a given
     rcu_barrier callback is stuck
   - mark idle Tasks-RCU-barrier callbacks
   - add *torture_stats_print() functions to print detailed diagnostics
     for Tasks-RCU variants
   - capture start time of rcu_barrier_tasks*() operation to help
     distinguish a hung barrier operation from a long series of barrier
     operations

  refscale:
   - add a TINY scenario to support tests of Tiny RCU and Tiny
     SRCU
   - optimize process_durations() operation

  rcuscale:
   - dump stacks of stalled rcu_scale_writer() instances and
     grace-period statistics when rcu_scale_writer() stalls
   - mark idle RCU-barrier callbacks to identify stuck RCU-barrier
     callbacks
   - print detailed grace-period and barrier diagnostics on
     rcu_scale_writer() hangs for Tasks-RCU variants
   - warn if async module parameter is specified for RCU implementations
     that do not have async primitives such as RCU Tasks Rude
   - make all writer tasks report upon hang
   - tolerate repeated GFP_KERNEL failure in rcu_scale_writer()
   - use special allocator for rcu_scale_writer()
   - NULL out top-level pointers to heap memory to avoid double-free
     bugs on modprobe failures
   - maintain per-task instead of per-CPU callbacks count to avoid any
     issues with migration of either tasks or callbacks
   - constify struct ref_scale_ops

  Fixes:
   - use system_unbound_wq for kfree_rcu work to avoid disturbing
     isolated CPUs

  Misc:
   - warn on unexpected rcu_state.srs_done_tail state
   - better define "atomic" for list_replace_rcu() and
     hlist_replace_rcu() routines
   - annotate struct kvfree_rcu_bulk_data with __counted_by()"

* tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (90 commits)
  rcu: Defer printing stall-warning backtrace when holding rcu_node lock
  rcu/nocb: Remove superfluous memory barrier after bypass enqueue
  rcu/nocb: Conditionally wake up rcuo if not already waiting on GP
  rcu/nocb: Fix RT throttling hrtimer armed from offline CPU
  rcu/nocb: Simplify (de-)offloading state machine
  context_tracking: Tag context_tracking_enabled_this_cpu() __always_inline
  context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching
  rcu: Update stray documentation references to rcu_dynticks_eqs_{enter, exit}()
  rcu: Rename rcu_momentary_dyntick_idle() into rcu_momentary_eqs()
  rcu: Rename rcu_implicit_dynticks_qs() into rcu_watching_snap_recheck()
  rcu: Rename dyntick_save_progress_counter() into rcu_watching_snap_save()
  rcu: Rename struct rcu_data .exp_dynticks_snap into .exp_watching_snap
  rcu: Rename struct rcu_data .dynticks_snap into .watching_snap
  rcu: Rename rcu_dynticks_zero_in_eqs() into rcu_watching_zero_in_eqs()
  rcu: Rename rcu_dynticks_in_eqs_since() into rcu_watching_snap_stopped_since()
  rcu: Rename rcu_dynticks_in_eqs() into rcu_watching_snap_in_eqs()
  rcu: Rename rcu_dynticks_eqs_online() into rcu_watching_online()
  context_tracking, rcu: Rename rcu_dynticks_curr_cpu_in_eqs() into rcu_is_watching_curr_cpu()
  context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*()
  refscale: Constify struct ref_scale_ops
  ...