linux-stable.git/drivers/char/hpet.c, branch linux-rolling-stable

hpet: Check ACPI_COMPANION() against NULL at probe time

2026-07-24T14:20:02+00:00

[ Upstream commit fa5e2952341b792b72d5410dbfcd0b2ac8046d2a ]

Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.

Accordingly, add a requisite ACPI_COMPANION() check against NULL to the
hpet driver.

Fixes: 71f0a267346b ("hpet: Convert ACPI driver to a platform one")
Signed-off-by: Rafael J. Wysocki 
Link: https://patch.msgid.link/4750803.LvFx2qVVIh@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

Merge tag 'char-misc-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2026-04-24T20:23:50+00:00

Pull char / misc / IIO / and others driver updates from Greg KH:
 "Here is the char/misc/iio and other smaller driver subsystem updates
  for 7.1-rc1. Lots of stuff in here, all tiny, but relevant for the
  different drivers they touch. Major points in here is:

   - the usual large set of new IIO drivers and updates for that
     subsystem (the large majority of this diffstat)

   - lots of comedi driver updates and bugfixes

   - coresight driver updates

   - interconnect driver updates and additions

   - mei driver updates

   - binder (both rust and C versions) updates and fixes

   - lots of other smaller driver subsystem updates and additions

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (405 commits)
  coresight: tpdm: fix invalid MMIO access issue
  mei: me: add nova lake point H DID
  mei: lb: add late binding version 2
  mei: bus: add mei_cldev_uuid
  w1: ds2490: drop redundant device reference
  bus: mhi: host: pci_generic: Add Telit FE912C04 modem support
  mei: csc: wake device while reading firmware status
  mei: csc: support controller with separate PCI device
  mei: convert PCI error to common errno
  mei: trace: print return value of pci_cfg_read
  mei: me: move trace into firmware status read
  mei: fix idle print specifiers
  mei: me: use PCI_DEVICE_DATA macro
  sonypi: Convert ACPI driver to a platform one
  misc: apds990x: fix all kernel-doc warnings
  most: usb: Use kzalloc_objs for endpoint address array
  hpet: Convert ACPI driver to a platform one
  misc: vmw_vmci: Fix spelling mistakes in comments
  parport: Remove completed item from to-do list
  char: remove unnecessary module_init/exit functions
  ...

hpet: replace deprecated mmap hook with mmap_prepare

2026-04-05T20:53:43+00:00

The f_op->mmap interface is deprecated, so update driver to use its
successor, mmap_prepare.

The driver previously used vm_iomap_memory(), so this change replaces it
with its mmap_prepare equivalent, mmap_action_simple_ioremap().

Link: https://lkml.kernel.org/r/094c5fcfb2459a4f6d791b1fb852b01e252a44d4.1774045440.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Reviewed-by: Suren Baghdasaryan 
Acked-by: Vlastimil Babka (SUSE) 
Cc: Alexander Shishkin 
Cc: Alexandre Torgue 
Cc: Al Viro 
Cc: Arnd Bergmann 
Cc: Bodo Stroesser 
Cc: Christian Brauner 
Cc: Clemens Ladisch 
Cc: David Hildenbrand 
Cc: David Howells 
Cc: Dexuan Cui 
Cc: Greg Kroah-Hartman 
Cc: Haiyang Zhang 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Jonathan Corbet 
Cc: K. Y. Srinivasan 
Cc: Liam Howlett 
Cc: Long Li 
Cc: Marc Dionne 
Cc: "Martin K. Petersen" 
Cc: Maxime Coquelin 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Miquel Raynal 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Ryan Roberts 
Cc: Vignesh Raghavendra 
Cc: Wei Liu 
Signed-off-by: Andrew Morton

hpet: Convert ACPI driver to a platform one

2026-04-02T15:06:03+00:00

In all cases in which a struct acpi_driver is used for binding a driver
to an ACPI device object, a corresponding platform device is created by
the ACPI core and that device is regarded as a proper representation of
underlying hardware.  Accordingly, a struct platform_driver should be
used by driver code to bind to that device.  There are multiple reasons
why drivers should not bind directly to ACPI device objects [1].

Overall, it is better to bind drivers to platform devices than to their
ACPI companions, so convert the HPET ACPI driver to a platform one.

While this is not expected to alter functionality, it changes sysfs
layout and so it will be visible to user space.

Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1]
Signed-off-by: Rafael J. Wysocki 
Link: https://patch.msgid.link/3611505.QJadu78ljV@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook

hpet: Use str_plural() to simplify the code

2025-08-19T10:50:36+00:00

Use the string choice helper function str_plural() to simplify the code.

Signed-off-by: Xichao Zhao 
Link: https://lore.kernel.org/r/20250811122358.542190-1-zhao.xichao@vivo.com
Signed-off-by: Greg Kroah-Hartman

hpet: Remove unnecessary NULL check before unregister_sysctl_table()

2025-05-21T12:52:59+00:00

unregister_sysctl_table() checks for NULL pointers internally.
Remove unneeded NULL check here.

Signed-off-by: Chen Ni 
Acked-by: Clemens Ladisch 
Link: https://lore.kernel.org/r/20250514032637.2317639-1-nichen@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman

treewide: const qualify ctl_tables where applicable

2025-01-28T12:48:37+00:00

Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.

Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.

Created this by running an spatch followed by a sed command:
Spatch:
    virtual patch

    @
    depends on !(file in "net")
    disable optional_qualifier
    @

    identifier table_name != {
      watchdog_hardlockup_sysctl,
      iwcm_ctl_table,
      ucma_ctl_table,
      memory_allocation_profiling_sysctls,
      loadpin_sysctl_table
    };
    @@

    + const
    struct ctl_table table_name [] = { ... };

sed:
    sed --in-place \
      -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
      kernel/utsname_sysctl.c

Reviewed-by: Song Liu 
Acked-by: Steven Rostedt (Google)  # for kernel/trace/
Reviewed-by: Martin K. Petersen  # SCSI
Reviewed-by: Darrick J. Wong  # xfs
Acked-by: Jani Nikula 
Acked-by: Corey Minyard 
Acked-by: Wei Liu 
Acked-by: Thomas Gleixner 
Reviewed-by: Bill O'Donnell 
Acked-by: Baoquan He 
Acked-by: Ashutosh Dixit 
Acked-by: Anna Schumaker 
Signed-off-by: Joel Granados

hpet: Switch to irq_get_nr_irqs()

2024-10-16T19:56:57+00:00

Use the irq_get_nr_irqs() function instead of the global variable
'nr_irqs'. Prepare for changing 'nr_irqs' from an exported global
variable into a variable with file scope.

Signed-off-by: Bart Van Assche 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20241015190953.1266194-8-bvanassche@acm.org