The linux-distros list relaxed their rules to try to adapt better to
how the Linux kernel works. Let's update the Coordination part to
explain why and when to contact them or not to and how to avoid trouble
in the future.

Link: https://www.openwall.com/lists/oss-security/2023/09/08/4
Cc: Kees Cook <keescook@chromium.org>
Cc: Solar Designer <solar@openwall.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20231015130959.26242-1-w@1wt.euSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This commit fixes a bug in commit 9ed98953 ("driver core: Functional
dependencies tracking support") where the device link status was
incorrectly updated in the driver unbind path before all the device's
resources were released.

Fixes: 9ed98953 ("driver core: Functional dependencies tracking support")
Cc: stable <stable@kernel.org>
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Closes: https://lore.kernel.org/all/20231014161721.f4iqyroddkcyoefo@pengutronix.de/Signed-off-by: Saravana Kannan <saravanak@google.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Matti Vaittinen <mazziesaccount@gmail.com>
Cc: James Clark <james.clark@arm.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231018013851.3303928-1-saravanak@google.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jump to err_out to avoid duplicating the code.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Link: https://lore.kernel.org/r/20231020160042.759439-1-mlombard@redhat.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct
irq_affinity_devres.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-hardening@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20231006201749.work.432-kees@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Constify APIs: _contains(), _overlaps(), _intersection(), _union().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230912165312.402422-3-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We have the next_resource() is used once and no user for the
next_resource_skip_children() outside of the for_each_resource().

Unify them by adding skip_children parameter to the next_resource().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230912165312.402422-2-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We have a few places where for_each_resource() is open coded.
Replace that by the macro. This makes code easier to read and
understand.

With this, compile r_next() only for CONFIG_PROC_FS=y.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230912165312.402422-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Since commit 636b21b5 ("PCI: Revoke mappings like devmem"), mmappable
sysfs entries have started to receive their f_mapping from the iomem
pseudo filesystem, so that CONFIG_IO_STRICT_DEVMEM is honored in sysfs
(and procfs) as well as in /dev/[k]mem.

This resulted in a userspace-visible regression:

1. Open a sysfs PCI resource file (eg. /sys/bus/pci/devices/*/resource0)
2. Use lseek(fd, 0, SEEK_END) to determine its size

Expected result: a PCI region size is returned.
Actual result: 0 is returned.

The reason is that PCI resource files residing in sysfs use
generic_file_llseek(), which relies on f_mapping->host inode to get the
file size. As f_mapping is now redefined, f_mapping->host points to an
anonymous zero-sized iomem_inode which has nothing to do with sysfs file
in question.

Implement a custom llseek method for sysfs PCI resources, which is
almost the same as proc_bus_pci_lseek() used for procfs entries.

This makes sysfs and procfs entries consistent with regards to seeking,
but also introduces userspace-visible changes to seeking PCI resources
in sysfs:

- SEEK_DATA and SEEK_HOLE are no longer supported;
- Seeking past the end of the file is prohibited while previously
  offsets up to MAX_NON_LFS were accepted (reading from these offsets
  was always invalid).
Signed-off-by: Valentine Sinitsyn <valesini@yandex-team.ru>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20230925084013.309399-2-valesini@yandex-team.ruSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

As of now, seeking in sysfs files is handled by generic_file_llseek().
There are situations where one may want to customize seeking logic:

- Many sysfs entries are fixed files while generic_file_llseek() accepts
  past-the-end positions. Not only being useless by itself, this
  also means a bug in userspace code will trigger not at lseek(), but at
  some later point making debugging harder.
- generic_file_llseek() relies on f_mapping->host to get the file size
  which might not be correct for all sysfs entries.
  See commit 636b21b5 ("PCI: Revoke mappings like devmem") as an example.

Implement llseek method to override this behavior at sysfs attribute
level. The method is optional, and if it is absent,
generic_file_llseek() is called to preserve backwards compatibility.
Signed-off-by: Valentine Sinitsyn <valesini@yandex-team.ru>
Link: https://lore.kernel.org/r/20230925084013.309399-1-valesini@yandex-team.ruSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Sparse reports the following:

fs/debugfs/file.c:942:9: sparse: sparse: incompatible types in comparison expression (different address spaces):
fs/debugfs/file.c:942:9: sparse:    char [noderef] __rcu *
fs/debugfs/file.c:942:9: sparse:    char *

rcu_assign_pointer() expects that it's assigning to pointers annotated
with __rcu. We can't annotate the generic struct file::private_data, so
cast it instead.

Fixes: 86b54881 ("debugfs: Add write support to debugfs_create_str()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309091933.BRWlSnCq-lkp@intel.com/Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com>
Link: https://lore.kernel.org/r/20230922134512.5126-1-quic_mdtipton@quicinc.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Replace custom and non-portable implementation of COUNT_ARGS().

Fixes: e64b674b ("software node: implement reference properties")
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Closes: https://lore.kernel.org/r/ZQoILN6QCjzosCOs@google.comSigned-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Closes: https://github.com/ClangBuiltLinux/linux/issues/1935Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230920153819.2069869-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no reason why the KUnit Tests for the property entry API can
only be built-in.  Add support for building these tests as a loadable
module, like is supported by most other tests.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/98388154383df9d4ced73946efd18318aeea50e2.1695820382.git.geert+renesas@glider.beSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The kernel documentation validator is not happy with:

  drivers/base/core.c:67: warning: Function parameter or member 'flags' not described in '__fwnode_link_add'

Add missing parameter description.

Fixes: 6a6dfdf8 ("driver core: fw_devlink: Allow marking a fwnode link as being part of a cycle")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230919195048.3197551-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Most of the struct fwnode_handle members are for exclusive use with
device links framework. Clarify this by adding a respective comment.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Link: https://lore.kernel.org/r/20230904104046.1682875-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The first parameter of devm_add_action(_or_reset) is a device.
The name 'release' is confusing because it is often used for
dr_release_t in the devres context.

Rename it to 'dev'. No functional change intended.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20230908135840.2362708-1-masahiroy@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

OF and ACPI currently are using asymmetrical APIs to check
for the firmware node type. Unify them by using is_*_node()
against struct fwnode_handle pointer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-4-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

With the temporary variable for the struct device pointer the code
looks better and slightly easier to read and parse by human being.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-3-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The usual pattern is to bail out on the error case. Besides that
one of the labels is redundant as we may return directly. Refactor
platform_device_add() and platform_dma_configure() accordingly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-2-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Starting from the commit 37c12e74 ("[DRIVER MODEL] Improved
dynamically allocated platform_device interface") the pdev expects
to be allocated beforehand or guaranteed to be non-NULL.

Hence the leftover check is now redundant (as we have no combined
calls like platform_device_add(platform_device_alloc(...)) in the
entire kernel source code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'kbuild-fixes-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix the module compression with xz so the in-kernel decompressor
   works

 - Document a kconfig idiom to express an optional dependency between
   modules

 - Make modpost, when W=1 is given, detect broken drivers that reference
   .exit.* sections

 - Remove unused code

* tag 'kbuild-fixes-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: remove stale code for 'source' symlink in packaging scripts
  modpost: Don't let "driver"s reference .exit.*
  vmlinux.lds.h: remove unused CPU_KEEP and CPU_DISCARD macros
  modpost: add missing else to the "of" check
  Documentation: kbuild: explain handling optional dependencies
  kbuild: Use CRC32 and a 1MiB dictionary for XZ compressed modules

Merge tag 'mm-hotfixes-stable-2023-10-01-08-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Fourteen hotfixes, eleven of which are cc:stable. The remainder
  pertain to issues which were introduced after 6.5"

* tag 'mm-hotfixes-stable-2023-10-01-08-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  Crash: add lock to serialize crash hotplug handling
  selftests/mm: fix awk usage in charge_reserved_hugetlb.sh and hugetlb_reparenting_test.sh that may cause error
  mm: mempolicy: keep VMA walk if both MPOL_MF_STRICT and MPOL_MF_MOVE are specified
  mm/damon/vaddr-test: fix memory leak in damon_do_test_apply_three_regions()
  mm, memcg: reconsider kmem.limit_in_bytes deprecation
  mm: zswap: fix potential memory corruption on duplicate store
  arm64: hugetlb: fix set_huge_pte_at() to work with all swap entries
  mm: hugetlb: add huge page size param to set_huge_pte_at()
  maple_tree: add MAS_UNDERFLOW and MAS_OVERFLOW states
  maple_tree: add mas_is_active() to detect in-tree walks
  nilfs2: fix potential use after free in nilfs_gccache_submit_read_data()
  mm: abstract moving to the next PFN
  mm: report success more often from filemap_map_folio_range()
  fs: binfmt_elf_efpic: fix personality for ELF-FDPIC

Pull misc driver fix from Greg KH:
 "Here is a single, much requested, fix for a set of misc drivers to
  resolve a much reported regression in the -rc series that has also
  propagated back to the stable releases. Sorry for the delay, lots of
  conference travel for a few weeks put me very far behind in patch
  wrangling.

  It has been reported by many to resolve the reported problem, and has
  been in linux-next with no reported issues"

* tag 'char-misc-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  misc: rtsx: Fix some platforms can not boot and move the l1ss judgment to probe

Pull tty / serial driver fixes from Greg KH:
 "Here are two tty/serial driver fixes for 6.6-rc4 that resolve some
  reported regressions:

   - revert a n_gsm change that ended up causing problems

   - 8250_port fix for irq data

  both have been in linux-next for over a week with no reported
  problems"

* tag 'tty-6.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "tty: n_gsm: fix UAF in gsm_cleanup_mux"
  serial: 8250_port: Check IRQ data before use

Pull x86 fixes from Ingo Molnar:
 "Misc fixes: a kerneldoc build warning fix, add SRSO mitigation for
  AMD-derived Hygon processors, and fix a SGX kernel crash in the page
  fault handler that can trigger when ksgxd races to reclaim the SECS
  special page, by making the SECS page unswappable"

* tag 'x86-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Resolves SECS reclaim vs. page fault for EAUG race
  x86/srso: Add SRSO mitigation for Hygon processors
  x86/kgdb: Fix a kerneldoc warning when build with W=1

Pull timer fix from Ingo Molnar:
 "Fix a spurious kernel warning during CPU hotplug events that may
  trigger when timer/hrtimer softirqs are pending, which are otherwise
  hotplug-safe and don't merit a warning"

* tag 'timers-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Tag (hr)timer softirq as hotplug safe

Pull scheduler fix from Ingo Molnar:
 "Fix a RT tasks related lockup/live-lock during CPU offlining"

* tag 'sched-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix live lock between select_fallback_rq() and RT push

Pull perf event fixes from Ingo Molnar:
 "Misc fixes: work around an AMD microcode bug on certain models, and
  fix kexec kernel PMI handlers on AMD systems that get loaded on older
  kernels that have an unexpected register state"

* tag 'perf-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd: Do not WARN() on every IRQ
  perf/x86/amd/core: Fix overflow reset on hotplug

Since commit d8131c29 ("kbuild: remove $(MODLIB)/source symlink"),
modules_install does not create the 'source' symlink.

Remove the stale code from builddeb and kernel.spec.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Drivers must not reference functions marked with __exit as these likely
are not available when the code is built-in.

There are few creative offenders uncovered for example in ARCH=amd64
allmodconfig builds. So only trigger the section mismatch warning for
W=1 builds.

The dual rule that drivers must not reference .init.* is implemented
since commit 0db25245 ("modpost: don't allow *driver to reference
.init.*") which however missed that .exit.* should be handled in the
same way.

Thanks to Masahiro Yamada and Arnd Bergmann who gave valuable hints to
find this improvement.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Remove the left-over of commit e24f6628 ("modpost: remove all
traces of cpuinit/cpuexit sections").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>

Without this 'else' statement, an "usb" name goes into two handlers:
the first/previous 'if' statement _AND_ the for-loop over 'devtable',
but the latter is useless as it has no 'usb' device_id entry anyway.

Tested with allmodconfig before/after patch; no changes to *.mod.c:

    git checkout v6.6-rc3
    make -j$(nproc) allmodconfig
    make -j$(nproc) olddefconfig

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/before

    # apply patch

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/after

    diff -r /tmp/before/ /tmp/after/
    # no difference

Fixes: acbef7b7 ("modpost: fix module autoloading for OF devices with generic compatible property")
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Pull ARM SoC fixes from Arnd Bergmann:
 "These are the latest bug fixes that have come up in the soc tree. Most
  of these are fairly minor. Most notably, the majority of changes this
  time are not for dts files as usual.

   - Updates to the addresses of the broadcom and aspeed entries in the
     MAINTAINERS file.

   - Defconfig updates to address a regression on samsung and a build
     warning from an unknown Kconfig symbol

   - Build fixes for the StrongARM and Uniphier platforms

   - Code fixes for SCMI and FF-A firmware drivers, both of which had a
     simple bug that resulted in invalid data, and a lesser fix for the
     optee firmware driver

   - Multiple fixes for the recently added loongson/loongarch "guts" soc
     driver

   - Devicetree fixes for RISC-V on the startfive platform, addressing
     issues with NOR flash, usb and uart.

   - Multiple fixes for NXP i.MX8/i.MX9 dts files, fixing problems with
     clock, gpio, hdmi settings and the Makefile

   - Bug fixes for i.MX firmware code and the OCOTP soc driver

   - Multiple fixes for the TI sysc bus driver

   - Minor dts updates for TI omap dts files, to address boot time
     warnings and errors"

* tag 'soc-fixes-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
  MAINTAINERS: Fix Florian Fainelli's email address
  arm64: defconfig: enable syscon-poweroff driver
  ARM: locomo: fix locomolcd_power declaration
  soc: loongson: loongson2_guts: Remove unneeded semicolon
  soc: loongson: loongson2_guts: Convert to devm_platform_ioremap_resource()
  soc: loongson: loongson_pm2: Populate children syscon nodes
  dt-bindings: soc: loongson,ls2k-pmc: Allow syscon-reboot/syscon-poweroff as child
  soc: loongson: loongson_pm2: Drop useless of_device_id compatible
  dt-bindings: soc: loongson,ls2k-pmc: Use fallbacks for ls2k-pmc compatible
  soc: loongson: loongson_pm2: Add dependency for INPUT
  arm64: defconfig: remove CONFIG_COMMON_CLK_NPCM8XX=y
  ARM: uniphier: fix cache kernel-doc warnings
  MAINTAINERS: aspeed: Update Andrew's email address
  MAINTAINERS: aspeed: Update git tree URL
  firmware: arm_ffa: Don't set the memory region attributes for MEM_LEND
  arm64: dts: imx: Add imx8mm-prt8mm.dtb to build
  arm64: dts: imx8mm-evk: Fix hdmi@3d node
  soc: imx8m: Enable OCOTP clock for imx8mm before reading registers
  arm64: dts: imx8mp-beacon-kit: Fix audio_pll2 clock
  arm64: dts: imx8mp: Fix SDMA2/3 clocks
  ...

Pull tracing fixes from Steven Rostedt:

 - Make sure 32-bit applications using user events have aligned access
   when running on a 64-bit kernel.

 - Add cond_resched in the loop that handles converting enums in
   print_fmt string is trace events.

 - Fix premature wake ups of polling processes in the tracing ring
   buffer. When a task polls waiting for a percentage of the ring buffer
   to be filled, the writer still will wake it up at every event. Add
   the polling's percentage to the "shortest_full" list to tell the
   writer when to wake it up.

 - For eventfs dir lookups on dynamic events, an event system's only
   event could be removed, leaving its dentry with no children. This is
   totally legitimate. But in eventfs_release() it must not access the
   children array, as it is only allocated when the dentry has children.

* tag 'trace-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Test for dentries array allocated in eventfs_release()
  tracing/user_events: Align set_bit() address for all archs
  tracing: relax trace_event_eval_update() execution with cond_resched()
  ring-buffer: Update "shortest_full" in polling

The dcache_dir_open_wrapper() could be called when a dynamic event is
being deleted leaving a dentry with no children. In this case the
dlist->dentries array will never be allocated. This needs to be checked
for in eventfs_release(), otherwise it will trigger a NULL pointer
dereference.

Link: https://lore.kernel.org/linux-trace-kernel/20230930090106.1c3164e9@rorschach.local.home

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fixes: ef36b4f9 ("eventfs: Remember what dentries were created on dir open")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

All architectures should use a long aligned address passed to set_bit().
User processes can pass either a 32-bit or 64-bit sized value to be
updated when tracing is enabled when on a 64-bit kernel. Both cases are
ensured to be naturally aligned, however, that is not enough. The
address must be long aligned without affecting checks on the value
within the user process which require different adjustments for the bit
for little and big endian CPUs.

Add a compat flag to user_event_enabler that indicates when a 32-bit
value is being used on a 64-bit kernel. Long align addresses and correct
the bit to be used by set_bit() to account for this alignment. Ensure
compat flags are copied during forks and used during deletion clears.

Link: https://lore.kernel.org/linux-trace-kernel/20230925230829.341-2-beaub@linux.microsoft.com
Link: https://lore.kernel.org/linux-trace-kernel/20230914131102.179100-1-cleger@rivosinc.com/

Cc: stable@vger.kernel.org
Fixes: 72357590 ("tracing/user_events: Use remote writes for event enablement")
Reported-by: Clément Léger <cleger@rivosinc.com>
Suggested-by: Clément Léger <cleger@rivosinc.com>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

When kernel is compiled without preemption, the eval_map_work_func()
(which calls trace_event_eval_update()) will not be preempted up to its
complete execution. This can actually cause a problem since if another
CPU call stop_machine(), the call will have to wait for the
eval_map_work_func() function to finish executing in the workqueue
before being able to be scheduled. This problem was observe on a SMP
system at boot time, when the CPU calling the initcalls executed
clocksource_done_booting() which in the end calls stop_machine(). We
observed a 1 second delay because one CPU was executing
eval_map_work_func() and was not preempted by the stop_machine() task.

Adding a call to cond_resched() in trace_event_eval_update() allows
other tasks to be executed and thus continue working asynchronously
like before without blocking any pending task at boot time.

Link: https://lore.kernel.org/linux-trace-kernel/20230929191637.416931-1-cleger@rivosinc.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

It was discovered that the ring buffer polling was incorrectly stating
that read would not block, but that's because polling did not take into
account that reads will block if the "buffer-percent" was set. Instead,
the ring buffer polling would say reads would not block if there was any
data in the ring buffer. This was incorrect behavior from a user space
point of view. This was fixed by commit 42fb0a1e by having the polling
code check if the ring buffer had more data than what the user specified
"buffer percent" had.

The problem now is that the polling code did not register itself to the
writer that it wanted to wait for a specific "full" value of the ring
buffer. The result was that the writer would wake the polling waiter
whenever there was a new event. The polling waiter would then wake up, see
that there's not enough data in the ring buffer to notify user space and
then go back to sleep. The next event would wake it up again.

Before the polling fix was added, the code would wake up around 100 times
for a hackbench 30 benchmark. After the "fix", due to the constant waking
of the writer, it would wake up over 11,0000 times! It would never leave
the kernel, so the user space behavior was still "correct", but this
definitely is not the desired effect.

To fix this, have the polling code add what it's waiting for to the
"shortest_full" variable, to tell the writer not to wake it up if the
buffer is not as full as it expects to be.

Note, after this fix, it appears that the waiter is now woken up around 2x
the times it was before (~200). This is a tremendous improvement from the
11,000 times, but I will need to spend some time to see why polling is
more aggressive in its wakeups than the read blocking code.

Link: https://lore.kernel.org/linux-trace-kernel/20230929180113.01c2cae3@rorschach.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 42fb0a1e ("tracing/ring-buffer: Have polling block on watermark")
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Tested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Pull dma-mapping fixes from Christoph Hellwig:

 - fix the narea calculation in swiotlb initialization (Ross Lagerwall)

 - fix the check whether a device has used swiotlb (Petr Tesarik)

* tag 'dma-mapping-6.6-2023-09-30' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: fix the check whether a device has used software IO TLB
  swiotlb: use the calculated number of areas

Pull iomap fixes from Darrick Wong:

 - Handle a race between writing and shrinking block devices by
   returning EIO

 - Fix a typo in a comment

* tag 'iomap-6.6-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: Spelling s/preceeding/preceding/g
  iomap: add a workaround for racy i_size updates on block devices