Pull printk fix from Petr Mladek:

 - Prevent refcount warning from code releasing a fwnode

* tag 'printk-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  lib/vsprintf: Fix %pfwf when current node refcount == 0

The IDA usually detects double-frees, but that detection failed to
consider the case when there are no nearby IDs allocated and so we have a
NULL bitmap rather than simply having a clear bit.  Add some tests to the
test-suite to be sure we don't inadvertently reintroduce this problem.
Unfortunately they're quite noisy so include a message to disregard
the warnings.

Reported-by: Zhenghan Wang <wzhmmmmm@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.

Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull misc fixes from Andrew Morton:
 "31 hotfixes. Ten of these address pre-6.6 issues and are marked
  cc:stable. The remainder address post-6.6 issues or aren't considered
  serious enough to justify backporting"

* tag 'mm-hotfixes-stable-2023-12-07-18-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits)
  mm/madvise: add cond_resched() in madvise_cold_or_pageout_pte_range()
  nilfs2: prevent WARNING in nilfs_sufile_set_segment_usage()
  mm/hugetlb: have CONFIG_HUGETLB_PAGE select CONFIG_XARRAY_MULTI
  scripts/gdb: fix lx-device-list-bus and lx-device-list-class
  MAINTAINERS: drop Antti Palosaari
  highmem: fix a memory copy problem in memcpy_from_folio
  nilfs2: fix missing error check for sb_set_blocksize call
  kernel/Kconfig.kexec: drop select of KEXEC for CRASH_DUMP
  units: add missing header
  drivers/base/cpu: crash data showing should depends on KEXEC_CORE
  mm/damon/sysfs-schemes: add timeout for update_schemes_tried_regions
  scripts/gdb/tasks: fix lx-ps command error
  mm/Kconfig: make userfaultfd a menuconfig
  selftests/mm: prevent duplicate runs caused by TEST_GEN_PROGS
  mm/damon/core: copy nr_accesses when splitting region
  lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly
  checkstack: fix printed address
  mm/memory_hotplug: fix error handling in add_memory_resource()
  mm/memory_hotplug: add missing mem_hotplug_lock
  .mailmap: add a new address mapping for Chester Lin
  ...

group_cpus_evenly() could be part of storage driver's error handler, such
as nvme driver, when may happen during CPU hotplug, in which storage queue
has to drain its pending IOs because all CPUs associated with the queue
are offline and the queue is becoming inactive.  And handling IO needs
error handler to provide forward progress.

Then deadlock is caused:

1) inside CPU hotplug handler, CPU hotplug lock is held, and blk-mq's
   handler is waiting for inflight IO

2) error handler is waiting for CPU hotplug lock

3) inflight IO can't be completed in blk-mq's CPU hotplug handler
   because error handling can't provide forward progress.

Solve the deadlock by not holding CPU hotplug lock in group_cpus_evenly(),
in which two stage spreads are taken: 1) the 1st stage is over all present
CPUs; 2) the end stage is over all other CPUs.

Turns out the two stage spread just needs consistent 'cpu_present_mask',
and remove the CPU hotplug lock by storing it into one local cache.  This
way doesn't change correctness, because all CPUs are still covered.

Link: https://lkml.kernel.org/r/20231120083559.285174-1-ming.lei@redhat.com
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Reported-by: Guangwu Zhang <guazhang@redhat.com>
Tested-by: Guangwu Zhang <guazhang@redhat.com>
Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <kbusch@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

A refcount issue can appeared in __fwnode_link_del() due to the
pr_debug() call:
  WARNING: CPU: 0 PID: 901 at lib/refcount.c:25 refcount_warn_saturate+0xe5/0x110
  Call Trace:
  <TASK>
  ...
  of_node_get+0x1e/0x30
  of_fwnode_get+0x28/0x40
  fwnode_full_name_string+0x34/0x90
  fwnode_string+0xdb/0x140
  ...
  vsnprintf+0x17b/0x630
  ...
  __fwnode_link_del+0x25/0xa0
  fwnode_links_purge+0x39/0xb0
  of_node_release+0xd9/0x180
  ...

Indeed, an fwnode (of_node) is being destroyed and so, of_node_release()
is called because the of_node refcount reached 0.
From of_node_release() several function calls are done and lead to
a pr_debug() calls with %pfwf to print the fwnode full name.
The issue is not present if we change %pfwf to %pfwP.

To print the full name, %pfwf iterates over the current node and its
parents and obtain/drop a reference to all nodes involved.

In order to allow to print the full name (%pfwf) of a node while it is
being destroyed, do not obtain/drop a reference to this current node.

Fixes: a92eb7621b9f ("lib/vsprintf: Make use of fwnode API to obtain node names and separators")
Cc: stable@vger.kernel.org
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20231114152655.409331-1-herve.codina@bootlin.com

Pull probes fixes from Masami Hiramatsu:

 - objpool: Fix objpool overrun case on memory/cache access delay
   especially on the big.LITTLE SoC. The objpool uses a copy of object
   slot index internal loop, but the slot index can be changed on
   another processor in parallel. In that case, the difference of 'head'
   local copy and the 'slot->last' index will be bigger than local slot
   size. In that case, we need to re-read the slot::head to update it.

 - kretprobe: Fix to use appropriate rcu API for kretprobe holder. Since
   kretprobe_holder::rp is RCU managed, it should use
   rcu_assign_pointer() and rcu_dereference_check() correctly. Also
   adding __rcu tag for finding wrong usage by sparse.

 - rethook: Fix to use appropriate rcu API for rethook::handler. The
   same as kretprobe, rethook::handler is RCU managed and it should use
   rcu_assign_pointer() and rcu_dereference_check(). This also adds
   __rcu tag for finding wrong usage by sparse.

* tag 'probes-fixes-v6.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  rethook: Use __rcu pointer for rethook::handler
  kprobes: consistent rcu api usage for kretprobe holder
  lib: objpool: fix head overrun on RK3588 SBC

Pull ACPI fixes from Rafael Wysocki:
 "This fixes a recently introduced build issue on ARM32 and a NULL
  pointer dereference in the ACPI backlight driver due to a design issue
  exposed by a recent change in the ACPI bus type code.

  Specifics:

   - Fix a recently introduced build issue on ARM32 platforms caused by
     an inadvertent header file breakage (Dave Jiang)

   - Eliminate questionable usage of acpi_driver_data() in the ACPI
     backlight cooling device code that leads to NULL pointer
     dereferences after recent ACPI core changes (Hans de Goede)"

* tag 'acpi-6.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: video: Use acpi_video_device for cooling-dev driver data
  ACPI: Fix ARM32 platforms compile issue introduced by fw_table changes

Pull more bcachefs bugfixes from Kent Overstreet:

 - bcache & bcachefs were broken with CFI enabled; patch for closures to
   fix type punning

 - mark erasure coding as extra-experimental; there are incompatible
   disk space accounting changes coming for erasure coding, and I'm
   still seeing checksum errors in some tests

 - several fixes for durability-related issues (durability is a device
   specific setting where we can tell bcachefs that data on a given
   device should be counted as replicated x times)

 - a fix for a rare livelock when a btree node merge then updates a
   parent node that is almost full

 - fix a race in the device removal path, where dropping a pointer in a
   btree node to a device would be clobbered by an in flight btree write
   updating the btree node key on completion

 - fix one SRCU lock hold time warning in the btree gc code - ther's
   still a bunch more of these to fix

 - fix a rare race where we'd start copygc before initializing the "are
   we rw" percpu refcount; copygc would think we were already ro and die
   immediately

* tag 'bcachefs-2023-11-29' of https://evilpiepirate.org/git/bcachefs: (23 commits)
  bcachefs: Extra kthread_should_stop() calls for copygc
  bcachefs: Convert gc_alloc_start() to for_each_btree_key2()
  bcachefs: Fix race between btree writes and metadata drop
  bcachefs: move journal seq assertion
  bcachefs: -EROFS doesn't count as move_extent_start_fail
  bcachefs: trace_move_extent_start_fail() now includes errcode
  bcachefs: Fix split_race livelock
  bcachefs: Fix bucket data type for stripe buckets
  bcachefs: Add missing validation for jset_entry_data_usage
  bcachefs: Fix zstd compress workspace size
  bcachefs: bpos is misaligned on big endian
  bcachefs: Fix ec + durability calculation
  bcachefs: Data update path won't accidentaly grow replicas
  bcachefs: deallocate_extra_replicas()
  bcachefs: Proper refcounting for journal_keys
  bcachefs: preserve device path as device name
  bcachefs: Fix an endianness conversion
  bcachefs: Start gc, copygc, rebalance threads after initing writes ref
  bcachefs: Don't stop copygc thread on device resize
  bcachefs: Make sure bch2_move_ratelimit() also waits for move_ops
  ...

Merge a fix for a recently introduced build issue on ARM32 platforms
caused by an inadvertent header file breakage (Dave Jiang).

* acpi-tables:
  ACPI: Fix ARM32 platforms compile issue introduced by fw_table changes