The platform profile driver is loaded even on platforms that do not have
ACPI enabled. The initialization of the sysfs entries was recently moved
from platform_profile_register() to the module init call, and those
entries need acpi_kobj to be initialized which is not the case when ACPI
is disabled.
This results in the following warning:
WARNING: CPU: 5 PID: 1 at fs/sysfs/group.c:131 internal_create_group+0xa22/0xdd8
Modules linked in:
CPU: 5 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.15.0-rc7-dirty #6 PREEMPT
Tainted: [W]=WARN
Hardware name: riscv-virtio,qemu (DT)
epc : internal_create_group+0xa22/0xdd8
ra : internal_create_group+0xa22/0xdd8
Call Trace:
internal_create_group+0xa22/0xdd8
sysfs_create_group+0x22/0x2e
platform_profile_init+0x74/0xb2
do_one_initcall+0x198/0xa9e
kernel_init_freeable+0x6d8/0x780
kernel_init+0x28/0x24c
ret_from_fork+0xe/0x18
Fix this by checking if ACPI is enabled before trying to create sysfs
entries.
Fixes: 77be5cacb2 ("ACPI: platform_profile: Create class for ACPI platform profile")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://patch.msgid.link/20250522141410.31315-1-alexghiti@rivosinc.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drivers usually call this method on error/exit paths and do not check
for it's return value, which is always 0 anyway, so make it void.
This is safe to do as currently all drivers use
devm_platform_profile_register().
While at it, improve the style and make the function safer by checking
for IS_ERR_OR_NULL before dereferencing the device pointer.
Signed-off-by: Kurt Borja <kuurtb@gmail.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://patch.msgid.link/20250212190308.21209-1-kuurtb@gmail.com
[ rjw: Minor changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When an attribute group is created with sysfs_create_group(), the
->sysfs_ops() callback is set to kobj_sysfs_ops, which sets the ->show()
and ->store() callbacks to kobj_attr_show() and kobj_attr_store()
respectively. These functions use container_of() to get the respective
callback from the passed attribute, meaning that these callbacks need to
be of the same type as the callbacks in 'struct kobj_attribute'.
However, ->show() and ->store() in the platform_profile driver are
defined for struct device_attribute with the help of DEVICE_ATTR_RO()
and DEVICE_ATTR_RW(), which results in a CFI violation when accessing
platform_profile or platform_profile_choices under /sys/firmware/acpi
because the types do not match:
CFI failure at kobj_attr_show+0x19/0x30 (target: platform_profile_choices_show+0x0/0x140; expected type: 0x7a69590c)
There is no functional issue from the type mismatch because the layout
of 'struct kobj_attribute' and 'struct device_attribute' are the same,
so the container_of() cast does not break anything aside from CFI.
Change the type of platform_profile_choices_show() and
platform_profile_{show,store}() to match the callbacks in
'struct kobj_attribute' and update the attribute variables to
match, which resolves the CFI violation.
Cc: All applicable <stable@vger.kernel.org>
Fixes: a2ff95e018 ("ACPI: platform: Add platform profile support")
Reported-by: John Rowley <lkml@johnrowley.me>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2047
Tested-by: John Rowley <lkml@johnrowley.me>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://patch.msgid.link/20250210-acpi-platform_profile-fix-cfi-violation-v3-1-ed9e9901c33a@kernel.org
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Multiple drivers may attempt to register platform profile handlers,
but only one may be registered and the behavior is non-deterministic
for which one wins. It's mostly controlled by probing order.
This can be problematic if one driver changes CPU settings and another
driver notifies the EC for changing fan curves.
Modify the ACPI platform profile handler to let multiple drivers
register platform profile handlers and abstract this detail from userspace.
To avoid undefined behaviors only offer profiles that are commonly
advertised across multiple handlers.
If any problems occur when changing profiles for any driver, then the
drivers that were already changed remain changed and the legacy sysfs
handler will report 'custom'.
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Tested-by: Matthew Schwartz <matthew.schwartz@linux.dev>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20241206031918.1537-21-mario.limonciello@amd.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/acpi/acpi_tad.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/acpi/platform_profile.o
Add the missing invocations of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drivers like thinkpad_acpi and ideapad_laptop call the
platform_profile_notify() helper when the profile is changed by hardware
(the embedded-controller/EC) in response to an EC handled hotkey.
This allows userspace to monitor for such changes by polling for POLLPRI
on the platform_profile sysfs file. But the profile can also be changed
underneath a userspace program monitoring it by anonther userspace program
storing a new value.
Add a sysfs_notify() call to platform_profile_store(), so that userspace
programs monitoring for changes also get notified in this case.
Also update the documentation to document that POLLPRI polling can be
used to watch for changes.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some devices, including most Microsoft Surface devices, have a platform
profile somewhere inbetween balanced and performance. More specifically,
adding this profile allows the following mapping on Surface devices:
Vendor Name Platform Profile
------------------------------------------
Battery Saver low-power
Recommended balanced
Better Performance balanced-performance
Best Performance performance
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After a rmmod thinkpad_acpi, lockdep pointed out this possible deadlock:
Our _show and _store sysfs attr functions get called with the kn->active
lock held for the sysfs attr and then take the profile_lock.
sysfs_remove_group() also takes the kn->active lock for the sysfs attr,
so if we call it with the profile_lock held, then we get an ABBA deadlock.
platform_profile_remove() must only be called by drivers which have
first *successfully* called platform_profile_register(). Anything else
is a driver bug. So the check for cur_profile being set before calling
sysfs_remove_group() is not necessary and it can be dropped.
It is safe to call sysfs_remove_group() without holding the profile_lock
since the attr-group group cannot be re-added until after we clear
cur_profile.
Change platform_profile_remove() to only hold the profile_lock while
clearing the cur_profile, fixing the deadlock.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drop the const qualifier from the static global cur_profile
pointer declaration.
This is a preparation patch for passing the cur_profile pointer as
parameter to the profile_get() and profile_set() callbacks so that
drivers dynamically allocating their driver-data struct, with their
platform_profile_handler struct embedded, can use this pointer to
get to their driver-data.
Note this also requires dropping the const from the pprof
platform_profile_register() function argument. Dropping this
const is not a problem, non of the queued up consumers of
platform_profile_register() actually pass in a const pointer.
Link: https://lore.kernel.org/linux-acpi/5e7a4d87-52ef-e487-9cc2-8e7094beaa08@redhat.com/
Link: https://lore.kernel.org/r/20210114073429.176462-2-jiaxun.yang@flygoat.com
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
[ hdegoede@redhat.com: Also remove const from platform_profile_register() ]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is the initial implementation of the platform-profile feature.
It provides the details discussed and outlined in the
sysfs-platform_profile document.
Many modern systems have the ability to modify the operating profile to
control aspects like fan speed, temperature and power levels. This
module provides a common sysfs interface that platform modules can register
against to control their individual profile options.
Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
[ rjw: Use full words in enum values names ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
