Pull Kbuild updates from Masahiro Yamada:

 - Remove the support for -O3 (CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3)

 - Fix error of rpm-pkg cross-builds

 - Support riscv for checkstack tool

 - Re-enable -Wformwat warnings for Clang

 - Clean up modpost, Makefiles, and misc scripts

* tag 'kbuild-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  modpost: remove .symbol_white_list field entirely
  modpost: remove unneeded .symbol_white_list initializers
  modpost: add PATTERNS() helper macro
  modpost: shorten warning messages in report_sec_mismatch()
  Revert "Kbuild, lto, workaround: Don't warn for initcall_reference in modpost"
  modpost: use more reliable way to get fromsec in section_rel(a)()
  modpost: add array range check to sec_name()
  modpost: refactor get_secindex()
  kbuild: set EXIT trap before creating temporary directory
  modpost: remove unused Elf_Sword macro
  Makefile.extrawarn: re-enable -Wformat for clang
  kbuild: add dtbs_prepare target
  kconfig: Qt5: tell the user which packages are required
  modpost: use sym_get_data() to get module device_table data
  modpost: drop executable ELF support
  checkstack: add riscv support for scripts/checkstack.pl
  kconfig: shorten the temporary directory name for cc-option
  scripts: headers_install.sh: Update config leak ignore entries
  kbuild: error out if $(INSTALL_MOD_PATH) contains % or :
  kbuild: error out if $(KBUILD_EXTMOD) contains % or :
  ...

Pull module updates from Luis Chamberlain:
 "For the 6.0 merge window the modules code shifts to cleanup and minor
  fixes effort. This becomes much easier to do and review now due to the
  code split to its own directory from effort on the last kernel
  release. I expect to see more of this with time and as we expand on
  test coverage in the future. The cleanups and fixes come from usual
  suspects such as Christophe Leroy and Aaron Tomlin but there are also
  some other contributors.

  One particular minor fix worth mentioning is from Helge Deller, where
  he spotted a *forever* incorrect natural alignment on both ELF section
  header tables:

    * .altinstructions
    * __bug_table sections

  A lot of back and forth went on in trying to determine the ill effects
  of this misalignment being present for years and it has been
  determined there should be no real ill effects unless you have a buggy
  exception handler. Helge actually hit one of these buggy exception
  handlers on parisc which is how he ended up spotting this issue. When
  implemented correctly these paths with incorrect misalignment would
  just mean a performance penalty, but given that we are dealing with
  alternatives on modules and with the __bug_table (where info regardign
  BUG()/WARN() file/line information associated with it is stored) this
  really shouldn't be a big deal.

  The only other change with mentioning is the kmap() with
  kmap_local_page() and my only concern with that was on what is done
  after preemption, but the virtual addresses are restored after
  preemption. This is only used on module decompression.

  This all has sit on linux-next for a while except the kmap stuff which
  has been there for 3 weeks"

* tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module: Replace kmap() with kmap_local_page()
  module: Show the last unloaded module's taint flag(s)
  module: Use strscpy() for last_unloaded_module
  module: Modify module_flags() to accept show_state argument
  module: Move module's Kconfig items in kernel/module/
  MAINTAINERS: Update file list for module maintainers
  module: Use vzalloc() instead of vmalloc()/memset(0)
  modules: Ensure natural alignment for .altinstructions and __bug_table sections
  module: Increase readability of module_kallsyms_lookup_name()
  module: Fix ERRORs reported by checkpatch.pl
  module: Add support for default value for module async_probe

Pull misc updates from Andrew Morton:
 "Updates to various subsystems which I help look after. lib, ocfs2,
  fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
  material this time"

* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  scripts/gdb: ensure the absolute path is generated on initial source
  MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
  mailmap: add linux.dev alias for Brendan Higgins
  mailmap: update Kirill's email
  profile: setup_profiling_timer() is moslty not implemented
  ocfs2: fix a typo in a comment
  ocfs2: use the bitmap API to simplify code
  ocfs2: remove some useless functions
  lib/mpi: fix typo 'the the' in comment
  proc: add some (hopefully) insightful comments
  bdi: remove enum wb_congested_state
  kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
  lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
  squashfs: support reading fragments in readahead call
  squashfs: implement readahead
  squashfs: always build "file direct" version of page actor
  Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
  fs/ocfs2: Fix spelling typo in comment
  ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
  proc: fix test for "vsyscall=xonly" boot option
  ...

Pull cgroup updates from Tejun Heo:
 "Several core optimizations:

   - threadgroup_rwsem write locking is skipped when configuring
     controllers in empty subtrees.

     Combined with CLONE_INTO_CGROUP, this allows the common static
     usage pattern to not grab threadgroup_rwsem at all (glibc still
     doesn't seem ready for CLONE_INTO_CGROUP unfortunately).

   - threadgroup_rwsem used to be put into non-percpu mode by default
     due to latency concerns in specific use cases. There's no reason
     for everyone else to pay for it. Make the behavior optional.

   - psi no longer allocates memory when disabled.

  ... along with some code cleanups"

* tag 'cgroup-for-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Skip subtree root in cgroup_update_dfl_csses()
  cgroup: remove "no" prefixed mount options
  cgroup: Make !percpu threadgroup_rwsem operations optional
  cgroup: Add "no" prefixed mount options
  cgroup: Elide write-locking threadgroup_rwsem when updating csses on an empty subtree
  cgroup.c: remove redundant check for mixable cgroup in cgroup_migrate_vet_dst
  cgroup.c: add helper __cset_cgroup_from_root to cleanup duplicated codes
  psi: dont alloc memory for psi by default

Pull documentation updates from Jonathan Corbet:
 "This was a moderately busy cycle for documentation, but nothing
  all that earth-shaking:

   - More Chinese translations, and an update to the Italian
     translations.

     The Japanese, Korean, and traditional Chinese translations
     are more-or-less unmaintained at this point, instead.

   - Some build-system performance improvements.

   - The removal of the archaic submitting-drivers.rst document,
     with the movement of what useful material that remained into
     other docs.

   - Improvements to sphinx-pre-install to, hopefully, give more
     useful suggestions.

   - A number of build-warning fixes

  Plus the usual collection of typo fixes, updates, and more"

* tag 'docs-6.0' of git://git.lwn.net/linux: (92 commits)
  docs: efi-stub: Fix paths for x86 / arm stubs
  Docs/zh_CN: Update the translation of sched-stats to 5.19-rc8
  Docs/zh_CN: Update the translation of pci to 5.19-rc8
  Docs/zh_CN: Update the translation of pci-iov-howto to 5.19-rc8
  Docs/zh_CN: Update the translation of usage to 5.19-rc8
  Docs/zh_CN: Update the translation of testing-overview to 5.19-rc8
  Docs/zh_CN: Update the translation of sparse to 5.19-rc8
  Docs/zh_CN: Update the translation of kasan to 5.19-rc8
  Docs/zh_CN: Update the translation of iio_configfs to 5.19-rc8
  doc:it_IT: align Italian documentation
  docs: Remove spurious tag from admin-guide/mm/overcommit-accounting.rst
  Documentation: process: Update email client instructions for Thunderbird
  docs: ABI: correct QEMU fw_cfg spec path
  doc/zh_CN: remove submitting-driver reference from docs
  docs: zh_TW: align to submitting-drivers removal
  docs: zh_CN: align to submitting-drivers removal
  docs: ko_KR: howto: remove reference to removed submitting-drivers
  docs: ja_JP: howto: remove reference to removed submitting-drivers
  docs: it_IT: align to submitting-drivers removal
  docs: process: remove outdated submitting-drivers.rst
  ...

Pull RCU updates from Paul McKenney:

 - Documentation updates

 - Miscellaneous fixes

 - Callback-offload updates, perhaps most notably a new
   RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be
   offloaded at boot time, regardless of kernel boot parameters.

   This is useful to battery-powered systems such as ChromeOS and
   Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot
   parameter prevents offloaded callbacks from interfering with
   real-time workloads and with energy-efficiency mechanisms

 - Polled grace-period updates, perhaps most notably making these APIs
   account for both normal and expedited grace periods

 - Tasks RCU updates, perhaps most notably reducing the CPU overhead of
   RCU tasks trace grace periods by more than a factor of two on a
   system with 15,000 tasks.

   The reduction is expected to increase with the number of tasks, so it
   seems reasonable to hypothesize that a system with 150,000 tasks
   might see a 20-fold reduction in CPU overhead

 - Torture-test updates

 - Updates that merge RCU's dyntick-idle tracking into context tracking,
   thus reducing the overhead of transitioning to kernel mode from
   either idle or nohz_full userspace execution for kernels that track
   context independently of RCU.

   This is expected to be helpful primarily for kernels built with
   CONFIG_NO_HZ_FULL=y

* tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits)
  rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings
  rcu: Diagnose extended sync_rcu_do_polled_gp() loops
  rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings
  rcutorture: Test polled expedited grace-period primitives
  rcu: Add polled expedited grace-period primitives
  rcutorture: Verify that polled GP API sees synchronous grace periods
  rcu: Make Tiny RCU grace periods visible to polled APIs
  rcu: Make polled grace-period API account for expedited grace periods
  rcu: Switch polled grace-period APIs to ->gp_seq_polled
  rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty
  rcu/nocb: Add option to opt rcuo kthreads out of RT priority
  rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread()
  rcu/nocb: Add an option to offload all CPUs on boot
  rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call
  rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order
  rcu/nocb: Add/del rdp to iterate from rcuog itself
  rcu/tree: Add comment to describe GP-done condition in fqs loop
  rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs()
  rcu/kvfree: Remove useless monitor_todo flag
  rcu: Cleanup RCU urgency state for offline CPU
  ...

Pull crypto updates from Herbert Xu:
"API:

   - Make proc files report fips module name and version

  Algorithms:

   - Move generic SHA1 code into lib/crypto

   - Implement Chinese Remainder Theorem for RSA

   - Remove blake2s

   - Add XCTR with x86/arm64 acceleration

   - Add POLYVAL with x86/arm64 acceleration

   - Add HCTR2

   - Add ARIA

  Drivers:

   - Add support for new CCP/PSP device ID in ccp"

* tag 'v5.20-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (89 commits)
  crypto: tcrypt - Remove the static variable initialisations to NULL
  crypto: arm64/poly1305 - fix a read out-of-bound
  crypto: hisilicon/zip - Use the bitmap API to allocate bitmaps
  crypto: hisilicon/sec - fix auth key size error
  crypto: ccree - Remove a useless dma_supported() call
  crypto: ccp - Add support for new CCP/PSP device ID
  crypto: inside-secure - Add missing MODULE_DEVICE_TABLE for of
  crypto: hisilicon/hpre - don't use GFP_KERNEL to alloc mem during softirq
  crypto: testmgr - some more fixes to RSA test vectors
  cyrpto: powerpc/aes - delete the rebundant word "block" in comments
  hwrng: via - Fix comment typo
  crypto: twofish - Fix comment typo
  crypto: rmd160 - fix Kconfig "its" grammar
  crypto: keembay-ocs-ecc - Drop if with an always false condition
  Documentation: qat: rewrite description
  Documentation: qat: Use code block for qat sysfs example
  crypto: lib - add module license to libsha1
  crypto: lib - make the sha1 library optional
  crypto: lib - move lib/sha1.c into lib/crypto/
  crypto: fips - make proc files report fips module name and version
  ...

CONFIG_KALLSYMS_ALL is required for kernel live patching which is a
common use case that is enabled in some major distros. Update the
Kconfig help text to reflect that.

While at it, s/e.g./i.e./ to match the text intention.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The difference in most compilers between `-O3` and `-O2` is mostly down
to whether loops with statically determinable trip counts are fully
unrolled vs unrolled to a multiple of SIMD width.

This patch is effectively a revert of
commit 15f5db60a137 ("kbuild,arc: add
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC") without re-adding
ARCH_CFLAGS

Ever since
commit cfdbc2e16e65 ("ARC: Build system: Makefiles, Kconfig, Linker
script")
ARC has been built with -O3, though the reason for doing so was not
specified in inline comments or the commit message. This commit does not
re-add -O3 to arch/arc/Makefile.

Folks looking to experiment with `-O3` (or any compiler flag for that
matter) may pass them along to the command line invocation of make:

$ make KCFLAGS=-O3

Code that looks to re-add an explicit Kconfig option for `-O3` should
provide:
1. A rigorous and reproducible performance profile of a reasonable
   userspace workload that demonstrates a hot loop in the kernel that
   would benefit from `-O3` over `-O2`.
2. Disassembly of said loop body before and after.
3. Provides stats on terms of increase in file size.

Link: https://lore.kernel.org/linux-kbuild/CA+55aFz2sNBbZyg-_i8_Ldr2e8o9dfvdSfHHuRzVtP2VMAUWPg@mail.gmail.com/
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

3942a9bd7b58 ("locking, rcu, cgroup: Avoid synchronize_sched() in
__cgroup_procs_write()") disabled percpu operations on threadgroup_rwsem
because the impiled synchronize_rcu() on write locking was pushing up the
latencies too much for android which constantly moves processes between
cgroups.

This makes the hotter paths - fork and exit - slower as they're always
forced into the slow path. There is no reason to force this on everyone
especially given that more common static usage pattern can now completely
avoid write-locking the rwsem. Write-locking is elided when turning on and
off controllers on empty sub-trees and CLONE_INTO_CGROUP enables seeding a
cgroup without grabbing the rwsem.

Restore the default percpu operations and introduce the mount option
"favordynmods" and config option CGROUP_FAVOR_DYNMODS for users who need
lower latencies for the dynamic operations.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Michal Koutn� <mkoutny@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Shmidt <dimitrysh@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>