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1,462,193 commits

Author SHA1 Message Date
Gabriel Almeida
721ee897a0 drm/amdgpu: move read_indexed_register to amdgpu_reg_access
The read_indexed_register helper is duplicated across multiple files
with identical logic.

Move it to amdgpu_reg_access.c as
amdgpu_read_indexed_register and update all users accordingly.

No functional changes intended.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Gabriel Almeida <gabrielsousa230@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:28:58 -04:00
Gabriel Almeida
86931542d0 drm/amdgpu: move program_aspm to amdgpu_nbio
The program_aspm helper is duplicated across multiple files with
identical logic.

Move it to amdgpu_nbio.c as amdgpu_nbio_program_aspm and update
all users accordingly.

Signed-off-by: Gabriel Almeida <gabrielsousa230@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:28:52 -04:00
Leo Chen
2eb0681ea7 drm/amd/display: Enable HUBP/OPTC/DPP power gating
[Why & How]
Enable driver power gating on DCN42 for HUBP OPTC
and DPP HW blocks.

Reviewed-by: Ovidiu Bunea <ovidiu.bunea@amd.com>
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Signed-off-by: Leo Chen <leo.chen@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:28:49 -04:00
Gaghik Khachatrian
27b7b67f21 drm/amd/display: Fix implicit conversion warning
[Why & How]
Fix implicit narrowing conversion warnings.

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Gaghik Khachatrian <gaghik.khachatrian@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:28:42 -04:00
Sheng Che Peng
5ec07d5204 tracepoint: Fix typo in tracepoint.h comment
Change "my" to "may" in the description of subsystem configurations.

Link: https://patch.msgid.link/20260422021819.1788091-1-synte4028@gmail.com
Signed-off-by: Sheng Che Peng <synte4028@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-04-28 14:28:29 -04:00
Breno Leitao
3b75dd76e6 tracing: branch: Fix inverted check on stat tracer registration
init_annotated_branch_stats() and all_annotated_branch_stats() check the
return value of register_stat_tracer() with "if (!ret)", but
register_stat_tracer() returns 0 on success and a negative errno on
failure. The inverted check causes the warning to be printed on every
successful registration, e.g.:

  Warning: could not register annotated branches stats

while leaving real failures silent. The initcall also returned a
hard-coded 1 instead of the actual error.

Invert the check and propagate ret so that the warning fires on real
errors and the initcall reports the correct status.

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: https://patch.msgid.link/20260420-tracing-v1-1-d8f4cd0d6af1@debian.org
Fixes: 002bb86d8d ("tracing/ftrace: separate events tracing and stats tracing engine")
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-04-28 14:28:29 -04:00
Markus Probst
2690d07158 rust: ACPI: fix missing match data for PRP0001
Export `acpi_of_match_device` function and use it to match the of device
table against ACPI PRP0001 in Rust.

This fixes id_info being None on ACPI PRP0001 devices.

Using `device_get_match_data` is not possible, because Rust stores an
index in the of device id instead of a data pointer. This was done this
way to provide a convenient and obvious API for drivers, which can be
evaluated in const context without the use of any unstable language
features.

Fixes: 7a718a1f26 ("rust: driver: implement `Adapter`")
Signed-off-by: Markus Probst <markus.probst@posteo.de>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> # ACPI
Link: https://patch.msgid.link/20260427-rust_acpi_prp0001-v6-1-6119b2a66183@posteo.de
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-04-28 20:28:28 +02:00
Gaghik Khachatrian
4f251a5e9f drm/amd/display: Update MCIF_ADDR macro to address IGT DWB regression
[Why]
A previous warning-fix commit updated type casts in the DCN3
mmhubbub code but missed updating the MCIF_ADDR macro to the
correct, fully parenthesized and casted version. This caused
a regression during DWB tests, where address values could be
misinterpreted, potentially leading to incorrect hardware
programming.

[How]
Updated the MCIF_ADDR macro in dcn30_mmhubbub.c to use the
proper parenthesization and type casting, ensuring correct
address handling. Removed redundant casts from REG_UPDATE
calls for improved clarity and consistency with current
coding standards.

Fixes: f4cdbb5d54 ("drm/amd/display: Fix implicit narrowing conversion warnings")
Reviewed-by: Clayton King <clayton.king@amd.com>
Signed-off-by: Gaghik Khachatrian <gaghik.khachatrian@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:27:35 -04:00
Charlene Liu
df4c0441c4 drm/amd/display: fix dual cursor shows on extend desktop
[why & how]
when dpp pipe power gating disabled in driver, disable_pipe
did not disable cursor so next time as long as this pipe
powers up, it will be visible.

port dcn314 logic: disable cursor when it should be pipe pg.

Reviewed-by: Roman Li <roman.li@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:27:26 -04:00
Charlene Liu
941983b42b drm/amd/display: fix hubp tmz field define mismatch
[why & how]
to make hubp surface_flip_registers field define mismatch
with dc_plane_address

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Reviewed-by: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:27:21 -04:00
Leo Chen
f07e2f7855 drm/amd/display: Enable driver power gating
[Why & How]
Enable driver power gating. Temporarily disable DIO power gating.

Reviewed-by: Ovidiu Bunea <ovidiu.bunea@amd.com>
Signed-off-by: Leo Chen <leo.chen@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 14:26:54 -04:00
Corey Minyard
a8aebe93a4 ipmi:ssif: NULL thread on error
Cleanup code was checking the thread for NULL, but it was possibly
a PTR_ERR() in one spot.

Spotted with static analysis.

Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/
Fixes: 75c486cb1b ("ipmi:ssif: Clean up kthread on errors")
Cc: <stable@vger.kernel.org> # 91eb7ec726: ipmi:ssif: Remove unnecessary indention
Cc: stable@vger.kernel.org
Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-28 12:59:15 -05:00
Corey Minyard
09dd798270 ipmi:si: Return state to normal if message allocation fails
There were places where nothing would get started if a message
allocation failed, so the driver needs to return to normal state.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org>
Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-28 12:59:15 -05:00
Corey Minyard
c4cca23696 ipmi: Add limits to event and receive message requests
The driver would just fetch events and receive messages until the
BMC said it was done.  To avoid issues with BMCs that never say they are
done, add a limit of 10 fetches at a time.

In addition, an si interface has an attn state it can return from the
hardware which is supposed to cause a flag fetch to see if the driver
needs to fetch events or message or a few other things.  If the attn
bit gets stuck, it's a similar problem.  So allow messages in between
flag fetches so the driver itself doesn't get stuck.

This is a more general fix than the previous fix for the specific bad
BMC, but should fix the more general issue of a BMC that won't stop
saying it has data.

This has been there from the beginning of the driver.  It's not a bug
per-se, but it is accounting for bugs in BMCs.

Reported-by: Matt Fleming <mfleming@cloudflare.com>
Closes: https://lore.kernel.org/lkml/20260415115930.3428942-1-matt@readmodwrite.com/
Fixes: <1da177e4c3> ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Corey Minyard <corey@minyard.net>
2026-04-28 12:59:08 -05:00
Yury Norov
7b81bc38e9 drm/amdgpu: fix build for CONFIG_DRM_FBDEV_EMULATION=n
The merge-commit 02e778f123 ("Merge tag 'amd-drm-next-7.1-2026-03-12' of
https://gitlab.freedesktop.org/agd5f/linux into drm-next") removes the stub
for drm_fb_helper_gem_is_fb(), so the buld gets broken if DRM_FBDEV_EMULATION
is not set.

‘drm_fb_helper_gem_is_fb’; did you mean ‘drm_fb_helper_from_client’? [-Wimplicit-function-declaration]
 1777 |                 if (!drm_fb_helper_gem_is_fb(dev->fb_helper, fb->obj[0])) {
      |                      ^~~~~~~~~~~~~~~~~~~~~~~
      |                      drm_fb_helper_from_client

Restore it.

Fixes: 02e778f123 ("Merge tag 'amd-drm-next-7.1-2026-03-12' of https://gitlab.freedesktop.org/agd5f/linux into drm-next")
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Yury Norov <ynorov@nvidia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-04-28 13:42:38 -04:00
Cheng-Yang Chou
d99f7a32f0 sched_ext: Fix scx_flush_disable_work() UAF race
scx_flush_disable_work() calls irq_work_sync() followed by
kthread_flush_work() to ensure that the disable kthread work has
fully completed before bpf_scx_unreg() frees the SCX scheduler.

However, a concurrent scx_vexit() (e.g., triggered by a watchdog stall)
creates a race window between scx_claim_exit() and irq_work_queue():

  CPU A (scx_vexit (watchdog))        CPU B (bpf_scx_unreg)
  ----                                ----
  scx_claim_exit()
    atomic_try_cmpxchg(NONE->kind)
  stack_trace_save()
  vscnprintf()
                                      scx_disable()
                                        scx_claim_exit() -> FAIL
                                      scx_flush_disable_work()
                                        irq_work_sync()      // no-op: not queued yet
                                        kthread_flush_work() // no-op: not queued yet
                                      kobject_put(&sch->kobj) -> free %sch
  irq_work_queue() -> UAF on %sch
  scx_disable_irq_workfn()
    kthread_queue_work() -> UAF

The root cause is that CPU B's scx_flush_disable_work() returns after
syncing an irq_work that has not yet been queued, while CPU A is still
executing the code between scx_claim_exit() and irq_work_queue().

Loop until exit_kind reaches SCX_EXIT_DONE or SCX_EXIT_NONE, draining
disable_irq_work and disable_work in each pass. This ensures that any
work queued after the previous check is caught, while also correctly
handling cases where no disable was triggered (e.g., the
scx_sub_enable_workfn() abort path).

Fixes: 510a270554 ("sched_ext: sync disable_irq_work in bpf_scx_unreg()")
Reported-by: https://sashiko.dev/#/patchset/20260424100221.32407-1-icheng%40nvidia.com
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-28 07:40:03 -10:00
Tejun Heo
4939721aad sched_ext: Collect ext_*.c include headers in build_policy.c
Move <linux/btf_ids.h> from ext.c and "ext_idle.h" from ext.c (plus its
self-include in ext_idle.c) into build_policy.c. Subsequent patches add
their headers the same way for consistency.

No functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-28 06:44:09 -10:00
Takashi Iwai
4873592845 HID: uclogic: Fix regression of input name assignment
The previous fix for adding the devm_kasprintf() return check in the
commit bd07f75120 ("HID: uclogic: Add NULL check in
uclogic_input_configured()") changed the condition of hi->input->name
assignment, and it resulted in missing the proper input device name
when no custom suffix is defined.

Restore the conditional to the original content to address the
regression.

Fixes: bd07f75120 ("HID: uclogic: Add NULL check in uclogic_input_configured()")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:37:01 +02:00
Dan Carpenter
ae4ac07733 HID: intel-thc-hid: Intel-quickspi: Fix some error codes
If we have a partial read that is supposed to be treated as failure but
in this code we forgot to set the error code.  Return -EINVAL.

Fixes: 9d8d51735a ("HID: intel-thc-hid: intel-quickspi: Add HIDSPI protocol implementation")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Even Xu <even.xu@intel.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:35:29 +02:00
Matthew Schwartz
3524900cc5 HID: hid-lenovo-go-s: restore OS_TYPE after resume from s2idle
The controller MCU does not persist OS_TYPE across power cycles. During
s2idle resume, the USB device may be power-cycled, causing the OS_TYPE
setting to revert to the default Windows value.

Add a reset_resume callback so that this is correctly restored after
resume.

Fixes: a23f3497bf ("HID: hid-lenovo-go-s: Add Lenovo Legion Go S Series HID Driver")
Reviewed-by: Derek J. Clark <derekjohn.clark@gmail.com>
Signed-off-by: Matthew Schwartz <matthew.schwartz@linux.dev>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:34:21 +02:00
Damien Dejean
55ce185884 HID: elan: Add support for ELAN SB974D touchpad
Elan SB974D touchpad uses ELAN_MT_I2C format to send HID reports. Add an
entry to match for the device and parse its vendor specific format.

Signed-off-by: Damien Dejean <damiendejean@google.com>
Signed-off-by: Kornel Dulęba <korneld@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:30:02 +02:00
Kuba Piecuch
163f8b7f9a sched_ext: Call wakeup_preempt() in local_dsq_post_enq()
There are several edge cases (see linked thread) where an IMMED task
can be left lingering on a local DSQ if an RT task swoops in at the
wrong time. All of these edge cases are due to rq->next_class being idle
even after dispatching a task to rq's local DSQ. We should bump
rq->next_class to &ext_sched_class as soon as we've inserted a task into
the local DSQ.

To optimize the common case of rq->next_class == &ext_sched_class,
only call wakeup_preempt() if rq->next_class is below EXT. If next_class
is EXT or above, wakeup_preempt() is a no-op anyway.

This lets us also simplify the preempt_curr() logic a bit since
wakeup_preempt() will call preempt_curr() for us if next_class is
below EXT.

Link: https://lore.kernel.org/all/DHZPHUFXB4N3.2RY28MUEWBNYK@google.com/
Signed-off-by: Kuba Piecuch <jpiecuch@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-28 06:28:48 -10:00
Rosalie Wanders
12bd440b66 HID: sony: add missing size validation for Rock Band 3 Pro instruments
This commit adds the missing size validation for Rock Band 3 PS3 Pro
instruments in sony_raw_event(), this prevents a malicious device from
allowing hid-sony to read out of bounds of the provided buffer.

Signed-off-by: Rosalie Wanders <rosalie@mailbox.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:28:32 +02:00
Rosalie Wanders
a4170b63ed HID: sony: add missing size validation for SMK-Link remotes
This commit adds the missing size validation for SMK-Link remotes in
sony_raw_event(), this prevents a malicious device from allowing
hid-sony to read out of bounds of the provided buffer.

I do not own these devices so the size check only forces that the buffer
is large enough for nsg_mrxu_parse_report().

Signed-off-by: Rosalie Wanders <rosalie@mailbox.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:27:26 +02:00
Rosalie Wanders
0f2b8466fb HID: sony: remove unneeded WARN_ON() in sony_leds_init()
This commit removes the unneeded WARN_ON() macro usage in
sony_leds_init(), this is unneeded because the sony_leds_init() function
call is already gated behind a SONY_LED_SUPPORT check in
sony_input_configured()

Signed-off-by: Rosalie Wanders <rosalie@mailbox.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:25:41 +02:00
Michael Zaidman
80c4bbb2b3 HID: ft260: validate i2c input report length
Add two checks to ft260_raw_event() to prevent out-of-bounds reads
from malicious or malfunctioning devices:

First, reject reports shorter than the 2-byte header (report ID +
length fields). Without this, even accessing xfer->length on a
1-byte report is an OOB read.

Second, validate xfer->length against the actual data capacity of
the received HID report. Each I2C data report ID (0xD0 through
0xDE) defines a different report size in the HID descriptor, so the
available payload varies per report. A corrupted length field could
cause memcpy to read beyond the report buffer.

Reported-by: Sebastián Josué Alba Vives <sebasjosue84@gmail.com>
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:24:52 +02:00
Rosalie Wanders
278dd04879 HID: sony: fix incorrect force-feedback check in sony_suspend()
This commit fixes the incorrect force-feedback check in sony_suspend(),
without this the check will always be true due to checking a constant
define that is never 0.

Signed-off-by: Rosalie Wanders <rosalie@mailbox.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2026-04-28 18:22:59 +02:00
Breno Leitao
0de4cb473a workqueue: fix devm_alloc_workqueue() va_list misuse
devm_alloc_workqueue() built a va_list and passed it as a single
positional argument to the variadic alloc_workqueue() macro:

	va_start(args, max_active);
	wq = alloc_workqueue(fmt, flags, max_active, args);
	va_end(args);

C does not allow forwarding a va_list through a ... parameter.
alloc_workqueue() expands to alloc_workqueue_noprof(), which runs
its own va_start() over its ... params, so the inner
vsnprintf(wq->name, sizeof(wq->name), fmt, args) in
__alloc_workqueue() received the outer va_list object as the first
variadic slot rather than the caller's actual format arguments.

Add a new static helper alloc_workqueue_va() that wraps
__alloc_workqueue() and runs wq_init_lockdep() on success, and
fold both alloc_workqueue_noprof() and devm_alloc_workqueue_noprof()
onto it as suggested by Tejun.

The wq_init_lockdep() step is required on the devm path
too, otherwise __flush_workqueue()'s on-stack
COMPLETION_INITIALIZER_ONSTACK_MAP would NULL-deref wq->lockdep_map.

No caller changes are required. devm_alloc_ordered_workqueue() is
a macro forwarding to devm_alloc_workqueue() and inherits the fix.
Two in-tree callers actively trigger the broken path on every probe:

  drivers/power/supply/mt6370-charger.c:889
  drivers/power/supply/max77705_charger.c:649

both of which use devm_alloc_ordered_workqueue(dev, "%s", 0,
dev_name(dev)).

A standalone reproducer module is available at[1].

Link: https://github.com/leitao/debug/blob/main/workqueue/valist/wq_va_test.c [1]
Fixes: 1dfc9d60a6 ("workqueue: devres: Add device-managed allocate workqueue")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-28 06:13:40 -10:00
Eduardo Vasconcelos
74ab7c4d73
platform/x86: thinkpad_acpi: Remove unneeded goto
Remove an unneeded goto statement in hotkey_kthread(). Since
the function has a single exit location with no cleanup code,
the jump provides no benefit. Per the kernel coding style,
returning directly is preferred over goto in such case [1].

[1] https://www.kernel.org/doc/html/latest/process/coding-style.html

Signed-off-by: Eduardo Vasconcelos <eduardo@eduardovasconcelos.com>
Tested-by: Eduardo Vasconcelos <eduardo@eduardovasconcelos.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://patch.msgid.link/20260425063936.9360-1-eduardo@eduardovasconcelos.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-04-28 19:00:43 +03:00
Bartosz Golaszewski
0f4a265107
platform/x86: meraki-mx100: use real software node references
The lpc_ich MFD driver now exposes the software node associated with the
its GPIO controller cell. Remove the dummy software node from the
meraki-mx100 driver and reference the real one instead.

Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260427-meraki-swnodes-v5-1-ad91cd306472@oss.qualcomm.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-04-28 19:00:38 +03:00
Thorsten Blum
b54a4676b3
sonypi: use strscpy() in sonypi_acpi_probe
strcpy() has been deprecated¹ because it performs no bounds checking on
the destination buffer, which can lead to buffer overflows. While the
current code works correctly, replace strcpy() with the safer strscpy()
to follow secure coding best practices.

¹ https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260424075755.305770-3-thorsten.blum@linux.dev
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-04-28 19:00:32 +03:00
Antoniu Miclaus
5aba4f94b2 iio: chemical: scd30: fix division by zero in write_raw
Add a zero check for val2 before using it as a divisor when setting the
sampling frequency. A user writing a zero fractional part to the
sampling_frequency sysfs attribute triggers a division by zero in the
kernel.

Fixes: 64b3d8b1b0 ("iio: chemical: scd30: add core driver")
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-04-28 16:36:09 +01:00
David Carlier
0d42e2c0bd iio: adc: npcm: fix unbalanced clk_disable_unprepare()
The driver acquired the ADC clock with devm_clk_get() and read its
rate, but never called clk_prepare_enable(). The probe error path and
npcm_adc_remove() both called clk_disable_unprepare() unconditionally,
causing the clk framework's enable/prepare counts to underflow on
probe failure or module unbind.

The issue went unnoticed because NPCM BMC firmware leaves the ADC
clock enabled at boot, so the driver happened to work in practice.

Switch to devm_clk_get_enabled() so the clock is properly enabled
during probe and automatically released by the device-managed
cleanup, and drop the now-redundant clk_disable_unprepare() from
both the probe error path and remove().

While at it, drop the duplicate error message on devm_request_irq()
failure since the IRQ core already logs it.

Fixes: 9bf85fbc9d ("iio: adc: add NPCM ADC driver")
Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-04-28 16:36:09 +01:00
Andy Shevchenko
7e5c0f97c6 iio: adc: nxp-sar-adc: Avoid division by zero
When Common Clock Framework is disabled, clk_get_rate() returns 0.
This is used as part of the divisor to perform nanosecond delays
with help of ndelay(). When the above condition occurs the compiler,
due to unspecified behaviour, is free to do what it wants to. Here
it saturates the value, which is logical from mathematics point of
view. However, the ndelay() implementation has set a reasonable
upper threshold and refuses to provide anything for such a long
delay. That's why code may not be linked under these circumstances.

To solve the issue, provide a wrapper that calls ndelay() when
the value is known not to be zero.

Fixes: 4434072a89 ("iio: adc: Add the NXP SAR ADC support for the s32g2/3 platforms")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603311958.ly6uROit-lkp@intel.com/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-04-28 16:36:09 +01:00
Svyatoslav Ryhel
bb21ee31f5 iio: Fix iio_multiply_value use in iio_read_channel_processed_scale
The function iio_multiply_value returns IIO_VAL_INT (1) on success or a
negative error number on failure, while iio_read_channel_processed_scale
should return an error code or 0. This creates a situation where the
expected result is treated as an error. Fix this by checking the
iio_multiply_value result separately, instead of passing it as a return
value.

Fixes: 05f958d003 ("iio: Improve iio_read_channel_processed_scale() precision")
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Reviewed-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-04-28 16:36:09 +01:00
Antoniu Miclaus
761e8b489e iio: gyro: adis16260: fix division by zero in write_raw
Add a validation check for the sampling frequency value before using it
as a divisor. A user writing zero to the sampling_frequency sysfs
attribute triggers a division by zero in the kernel.

Fixes: 089a41985c ("staging: iio: adis16260 digital gyro driver")
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2026-04-28 16:36:09 +01:00
Radu Sabau
1a77271931 iio: adc: ad4695: Fix call ordering in offload buffer postenable
ad4695_enter_advanced_sequencer_mode() was called after
spi_offload_trigger_enable(). That is wrong because
ad4695_enter_advanced_sequencer_mode() issues regular SPI transfers to
put the ADC into advanced sequencer mode, and not all SPI offload capable
controllers support regular SPI transfers while offloading is enabled.

Fix this by calling ad4695_enter_advanced_sequencer_mode() before
spi_offload_trigger_enable(), so the ADC is fully configured before the
first CNV pulse can occur. This is consistent with the same constraint
that already applies to the BUSY_GP_EN write above it.

Update the error unwind labels accordingly: add err_exit_conversion_mode
so that a failure of spi_offload_trigger_enable() correctly exits
conversion mode before clearing BUSY_GP_EN.

Fixes: f09f140e3e ("iio: adc: ad4695: Add support for SPI offload")
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Radu Sabau <radu.sabau@analog.com>
Cc: Stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2026-04-28 16:36:09 +01:00
Felix Gu
b66f922f6a iio: light: veml6070: Fix resource leak in probe error path
The driver calls i2c_new_dummy_device() to create a dummy device,
then calls i2c_smbus_write_byte(). If i2c_smbus_write_byte() fails and
returns, the cleanup via devm_add_action_or_reset() was never registered,
so the dummy device leaks.

Switch to devm_i2c_new_dummy_device() which registers cleanup atomically
with device creation, eliminating the error-path window.

Fixes: 7501bff87c ("iio: light: veml6070: add action for i2c_unregister_device")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2026-04-28 16:36:09 +01:00
Pengpeng Hou
673478bc29 iio: chemical: mhz19b: reject oversized serial replies
mhz19b_receive_buf() appends each serdev chunk into the fixed
MHZ19B_CMD_SIZE receive buffer and advances buf_idx by len without
checking that the chunk fits in the remaining space. A large callback
can therefore overflow st->buf before the command path validates the
reply.

Reset the reply state before each command and reject oversized serial
replies before copying them into the fixed buffer. When an oversized
reply is detected, wake the waiter and report -EMSGSIZE instead of
overwriting st->buf.

Fixes: 4572a70b36 ("iio: chemical: Add support for Winsen MHZ19B CO2 sensor")
Cc: stable@vger.kernel.org
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Acked-by: Gyeyoung Baek <gye976@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2026-04-28 16:36:08 +01:00
Christofer Jonason
852534744c iio: adc: xilinx-xadc: Fix sequencer mode in postdisable for dual mux
xadc_postdisable() unconditionally sets the sequencer to continuous
mode. For dual external multiplexer configurations this is incorrect:
simultaneous sampling mode is required so that ADC-A samples through
the mux on VAUX[0-7] while ADC-B simultaneously samples through the
mux on VAUX[8-15]. In continuous mode only ADC-A is active, so
VAUX[8-15] channels return incorrect data.

Since postdisable is also called from xadc_probe() to set the initial
idle state, the wrong sequencer mode is active from the moment the
driver loads.

The preenable path already uses xadc_get_seq_mode() which returns
SIMULTANEOUS for dual mux. Fix postdisable to do the same.

Fixes: bdc8cda1d0 ("iio:adc: Add Xilinx XADC driver")
Cc: stable@vger.kernel.org
Signed-off-by: Christofer Jonason <christofer.jonason@guidelinegeo.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Salih Erim <salih.erim@amd.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2026-04-28 16:36:08 +01:00
Christian Brauner
a33d6583ce
Merge patch series "eventpoll: clarity refactor"
Christian Brauner <brauner@kernel.org> says:

The recent UAF series (a6dc643c69 and follow-ups) rode on
invariants in fs/eventpoll.c that were nowhere documented and had
to be reverse-engineered from the code: the lifetime relationships
between struct eventpoll, struct epitem, and struct file, the three
removal paths coordinating via epi_fget() pins and ep->mtx, the
ovflist sentinel-encoded scan state machine, the POLLFREE
release/acquire handshake, and the loop / path check globals
serialized by epnested_mutex. The fix was correct but the next
person to touch this code will hit the same learning curve.

This adds a bunch of documentation (a bunch of swearwords were removed
by having an llm go over it) and refactors. The end goal is hopefully a
bit more pallatable than what this is right now. No functional changes
intended yet.

This series codifies those invariants in source and tightens the
surrounding structure.

First there are a couple of pure documentation changes. A top-of-file
overview with field-protection tables for struct eventpoll and struct
epitem, a section gathering the loop-check / path-check globals next to
their declarations, labelled comments on the two sides of the POLLFREE
handshake, refreshed comments on epi_fget() and ep_remove_file() (whose
contract the UAF fix re-shaped), and a docblock on
ep_clear_and_put() that names its two-pass structure as load-bearing.

Next are a couple of mechanical naming cleanups.
ep_refcount_dec_and_test() -> ep_put() to pair with ep_get(); the unused
depth argument dropped from epoll_mutex_lock() (all three callers passed
zero); attach_epitem() -> ep_attach_file() for ep_remove_file()
symmetry; and the CONFIG_KCMP block relocated next to CONFIG_COMPAT so
the hot-path code is contiguous.

Next are a couple of changes that extract long bodies into named
helpers. ep_insert() splits into ep_alloc_epitem() and
ep_register_epitem(); ep_clear_and_put()'s two passes become
ep_drain_pollwaits() and ep_drain_tree() so the ordering invariant is
enforced by the call sequence rather than convention; the per-event
delivery loop body extracts from ep_send_events() as ep_deliver_event();
and the ep->mtx + epnested_mutex acquisition dance lifts out of
do_epoll_ctl() into ep_ctl_lock() / ep_ctl_unlock(), with a return value
that doubles as the @full_check argument to ep_insert().

Next are a couple of changes that address sentinel and predicate sprawl.
The EP_UNACTIVE_PTR overload (meaning "no scan in progress" on
ep->ovflist and "epi not on ovflist" on epi->next) is hidden behind
named helpers (ep_is_scanning, epi_on_ovflist, ...); epi->next is
renamed to epi->ovflist_next and the local txlist to scan_batch; and
is_file_epoll(), ep_is_linked(), ep_events_available() are converted to
return bool to match their already-boolean bodies.

And last we move the per-CTL_ADD scratch state (tfile_check_list,
path_count[], inserting_into) from file-scope globals into a
stack-allocated struct ep_ctl_ctx plumbed through the loop / path check
chain. loop_check_gen stays at file scope because the stamp it leaves on
ep->gen across calls must not collide with a future walk.

The load-bearing invariants the UAF series closed are preserved
verbatim: the epi_fget() pin in ep_remove(), the ordering of
ep_unregister_pollwait() before ep_remove_file() / ep_remove_epi()
in all three removal paths, kfree_rcu(epi) and kfree_rcu(ep), the
POLLFREE smp_store_release / smp_load_acquire pair on pwq->whead,
ep->lock IRQ-safety, the mutex_lock_nested() subclass arithmetic
in ep_insert (subclass 0 outer, 1 for tep) and __ep_eventpoll_poll
/ ep_loop_check_proc (depth-based), and the WARN_ON_ONCE contract
on ep_put() in ep_remove().

* patches from https://patch.msgid.link/20260424-work-epoll-rework-v1-0-249ed00a20f3@kernel.org:
  eventpoll: hoist CTL_ADD scratch state into struct ep_ctl_ctx
  eventpoll: use bool for predicate helpers
  eventpoll: rename epi->next and txlist for clarity
  eventpoll: wrap EP_UNACTIVE_PTR in typed sentinel helpers
  eventpoll: extract lock dance from do_epoll_ctl() into ep_ctl_lock()
  eventpoll: extract ep_deliver_event() from ep_send_events()
  eventpoll: split ep_clear_and_put() into drain helpers
  eventpoll: split ep_insert() into alloc + register stages
  eventpoll: relocate KCMP helpers near compat syscalls
  eventpoll: rename attach_epitem() to ep_attach_file()
  eventpoll: drop unused depth argument from epoll_mutex_lock()
  eventpoll: rename ep_refcount_dec_and_test() to ep_put()
  eventpoll: document ep_clear_and_put() two-pass pattern
  eventpoll: refresh epi_fget() / ep_remove_file() comments
  eventpoll: clarify POLLFREE handshake comments
  eventpoll: document loop-check / path-check globals
  eventpoll: expand top-of-file overview / locking doc

Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-0-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:36 +02:00
Christian Brauner
e09c77d940
eventpoll: hoist CTL_ADD scratch state into struct ep_ctl_ctx
Three globals were shared between the loop check and the path check
paths: tfile_check_list (chain of epitems_head to walk afterwards),
path_count[] (per-depth wakeup-path tally) and inserting_into
(cycle-detection sentinel). All three are scratch state used only
during a single EPOLL_CTL_ADD full_check, yet they sit at file
scope and rely on epnested_mutex for exclusion.

The area has had three bugs in the last year -- CVE-2025-38349,
f2e467a482 ("eventpoll: Fix semi-unbounded recursion"), and
fdcfce9307 ("eventpoll: Fix integer overflow in
ep_loop_check_proc()") -- all rooted in the shared-mutable-global
pattern being hard to reason about.

Collect the three into a stack-allocated struct ep_ctl_ctx:

    struct ep_ctl_ctx {
        struct eventpoll   *inserting_into;
        struct epitems_head *tfile_check_list;
        int                 path_count[PATH_ARR_SIZE];
    };

do_epoll_ctl() zero-initializes one on its stack and plumbs it
through ep_ctl_lock() / ep_ctl_unlock() / ep_insert() /
ep_register_epitem() / list_file() / ep_loop_check() /
ep_loop_check_proc() / reverse_path_check() /
reverse_path_check_proc() / path_count_inc() / path_count_init() /
clear_tfile_check_list(). Non-nested inserts leave the ctx zeroed
and skip the machinery entirely.

With the scratch state in ctx:
  - tfile_check_list no longer has an EP_UNACTIVE_PTR sentinel --
    NULL is the obvious "empty" value and the zero-init handles it
    for free;
  - path_count[] is no longer an array global that could be touched
    in unexpected orderings;
  - inserting_into is scoped to the exact call that set it.

loop_check_gen stays as a file-scope monotonic counter, because the
stamp left on ep->gen by a completed walk must not equal the stamp
of a future walk -- something a stack-local value cannot guarantee
across calls. It remains protected by epnested_mutex for the bump
and read lockless for the "do we need a full check" trigger in
ep_ctl_lock().

Every bail-out that existed before (the ELOOP on cycle, the path
limit check, the unbounded-recursion cap, the +1 overflow guard) is
preserved verbatim; only the data they operate on moved from file
scope to the stack ctx.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-17-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:29 +02:00
Christian Brauner
23431ae93a
eventpoll: use bool for predicate helpers
Three inline predicates -- is_file_epoll(), ep_is_linked(),
ep_events_available() -- were declared to return int even though
their only use is as a truthy test and their bodies are already
boolean expressions. ep_has_wakeup_source(), in the same file,
returns bool, so the convention was already inconsistent.

Convert all three to return bool. Rewrite ep_events_available()'s
verbose kerneldoc to the same one-line style the rest of the
predicates use now.

ep_poll()'s local eavail variable stores the result of
ep_events_available() (already boolean), ep_busy_loop() (returns
bool), and list_empty() (int but tested as boolean). Split it out
of the combined int declaration and give it bool type; replace the
one "eavail = 1" after a wakeup with "eavail = true" to match.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-16-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:29 +02:00
Christian Brauner
f38567bb63
eventpoll: rename epi->next and txlist for clarity
Two list-related names were confusing in isolation:

  struct epitem::next
    A singly-linked link slot used only when an epi is queued on
    ep->ovflist during an ep_start_scan/ep_done_scan window. The
    bare name "next" suggests a generic list link and doesn't say
    which list it belongs to.

  txlist
    The caller-local list_head used by ep_send_events() and
    __ep_eventpoll_poll() to hold the batch of items stolen from
    ep->rdllist for the current scan. "txlist" ("transmission
    list") is abbreviated and overloaded: it doesn't distinguish
    itself from ep->rdllist or ep->ovflist at a glance.

Rename for what each actually is:

  struct epitem::next   -> struct epitem::ovflist_next
  local txlist          -> scan_batch

With these in place:
  - epi->ovflist_next reads as "this is the ep->ovflist link slot",
    matching the rdllink pattern above it.
  - scan_batch reads as "the batch currently being scanned", clearly
    distinct from rdllist (canonical ready list) and ovflist
    (scan-window overflow).

ep->rdllist and ep->ovflist struct field names are preserved -- they
are long-standing interface-facing identifiers, and the new inline
helpers (ep_is_scanning, epi_on_ovflist, ...) already hide the
sentinel semantics at call sites.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-15-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:29 +02:00
Christian Brauner
0dcb726466
eventpoll: wrap EP_UNACTIVE_PTR in typed sentinel helpers
ep->ovflist and epi->next both use EP_UNACTIVE_PTR (a cast to
(void *)-1) as a sentinel, with distinct meanings at each site:

  ep->ovflist == EP_UNACTIVE_PTR         no scan in progress
  epi->next   == EP_UNACTIVE_PTR         epi not on ovflist

Call sites had to know the sentinel's value and, by convention, what
it meant in each context. Hide both behind inline helpers:

  ep_is_scanning(ep)       predicate for "scan in progress"
  ep_enter_scan(ep)        WRITE_ONCE flip to NULL (scan start)
  ep_exit_scan(ep)         WRITE_ONCE flip to sentinel (scan end)
  epi_on_ovflist(epi)      predicate for "epi is on ovflist"
  epi_clear_ovflist(epi)   clear epi's ovflist link slot

Convert ep_events_available(), ep_start_scan(), ep_done_scan(),
ep_poll_callback(), and ep_alloc_epitem() to use the wrappers. The
ovflist state-machine transitions are now named, not encoded in
sentinel comparisons, and the top-of-file "Ready-list state machine"
section is the single place that spells out the sentinel's meaning.

ep_alloc() keeps the raw "ep->ovflist = EP_UNACTIVE_PTR" init (no
concurrent access at that point) with an inline "not scanning"
comment, and the tfile_check_list sentinel is left alone -- it will
disappear entirely when the loop-check globals move into a
stack-allocated ep_ctl_ctx in a later commit.

Also rework ep_done_scan()'s for-loop: the combined initializer +
update clause that advanced nepi AND cleared epi->next in one step
was clever but hard to read; splitting the update into two
statements inside the body makes the epi_clear_ovflist() call
visible.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-14-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:29 +02:00
Christian Brauner
8d5278e05b
eventpoll: extract lock dance from do_epoll_ctl() into ep_ctl_lock()
do_epoll_ctl() interleaved three concerns in one body: input
validation, the ep->mtx + epnested_mutex acquisition dance for
EPOLL_CTL_ADD on potentially-nested topologies, and the op dispatch
with final unlock. The middle concern is the error-prone one; the
error_tgt_fput label existed mainly to orchestrate it.

Extract the acquisition as ep_ctl_lock() and the release as
ep_ctl_unlock(). ep_ctl_lock() always takes ep->mtx and, for
EPOLL_CTL_ADD on a topology that can change, additionally runs the
loop / path check under epnested_mutex. The return value is a
ternary:

   0        ep->mtx held.
   1        ep->mtx AND epnested_mutex held (full-check mode).
   -errno   failure, no locks held.

The non-negative value doubles as the @full_check argument to
ep_insert() and as the argument to ep_ctl_unlock(), so the caller
neither needs an out-parameter nor a separate boolean:

   full_check = ep_ctl_lock(ep, op, epfile, tfile, nonblock);
   if (full_check < 0)
       return full_check;
   ...
   ep_ctl_unlock(ep, full_check);

ep_ctl_unlock() drops ep->mtx and, if full_check == 1, clears
tfile_check_list, bumps loop_check_gen, and drops epnested_mutex --
mirroring the old error_tgt_fput block.

With that in place do_epoll_ctl()'s preconditions become direct
returns (no locks held, nothing to clean up), the acquisition is a
single call, the op dispatch is unchanged, and the epilogue is a
single ep_ctl_unlock() before return. The error_tgt_fput label goes
away.

The two loop_check_gen bumps (one at the start of the full check,
one after) are preserved inside ep_ctl_lock() / ep_ctl_unlock(),
keeping the invariant that ep->gen stamps left on per-eventpoll
caches never equal loop_check_gen after the check completes.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-13-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:28 +02:00
Christian Brauner
499a5e7f4a
eventpoll: extract ep_deliver_event() from ep_send_events()
ep_send_events()'s body covered two concerns: per-item work (PM
wakeup-source bookkeeping, re-poll, copy_to_user, level-trigger
re-queue, EPOLLONESHOT mask clear) and the scan-level accumulator
(maxevents cap, EFAULT preservation, txlist/rdllist splice).

Extract the per-item work as ep_deliver_event(), which returns a
tri-state int:

  1       one event was delivered; caller advances the counter,
  0       re-poll produced no caller-requested events (item drops
          out of the ready list; a future callback will re-queue),
 -EFAULT  copy_to_user() faulted; item is already re-inserted at
          the head of the txlist so ep_done_scan() splices it back
          to rdllist.

The per-item comments (PM ordering, the "sole writer to rdllist"
invariant for the LT re-queue, the EFAULT semantics) move into
ep_deliver_event(). ep_send_events() reduces to the fatal-signal
short-circuit, scan bracket, and a short txlist walk that accumulates
the deliveries and preserves the "first error wins" EFAULT contract
(res = delivered only if no event was previously delivered; otherwise
the success count is returned and -EFAULT is reported on the next
call).

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-12-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:28 +02:00
Christian Brauner
08fe3679a8
eventpoll: split ep_clear_and_put() into drain helpers
ep_clear_and_put()'s two-pass walk is the main way an ep file close
tears down its state, and the ordering between the passes is
load-bearing (see previous commit's docblock). Give each pass its
own function so the ordering is enforced by the call sequence in
ep_clear_and_put() rather than by convention inside one body.

ep_drain_pollwaits() carries out Pass 1: walk the rbtree and
ep_unregister_pollwait() each epi. The function-level comment names
it as Pass 1 and spells out the synchronization contract with
ep_poll_callback().

ep_drain_tree() carries out Pass 2: walk the rbtree and ep_remove()
each epi, capturing rb_next() before each erase. The comment names
it as Pass 2 and documents the hand-off with a concurrent
eventpoll_release_file() (removal path C).

ep_clear_and_put() keeps the poll-on-ep wakeup, ep->mtx bracketing,
and ep_put() + conditional ep_free(), and its docblock shrinks to
the high-level summary; the per-pass detail moved into the helpers.

No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-11-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:28 +02:00
Christian Brauner
e0e35f4cb9
eventpoll: split ep_insert() into alloc + register stages
ep_insert() was 130 lines and mixed four concerns in one body: user
quota charge and epitem allocation, attach-into-file-hlist plus
rbtree insert plus target-ep locking, reverse-path + EPOLLWAKEUP +
poll-queue install with rollback, and ready-list publication.
Factor the first two concerns into named helpers so the body reduces
to orchestration.

ep_alloc_epitem() charges the user's epoll_watches quota, allocates
a fresh epitem, and initializes its fields. On failure it returns
ERR_PTR(-ENOSPC) or ERR_PTR(-ENOMEM); on success the epi is not yet
linked into anything.

ep_register_epitem() installs @epi into @tfile's f_ep hlist and
@ep's rbtree, optionally chains @tfile onto tfile_check_list for the
path check, takes the tep->mtx nested lock for the epoll-watches-
epoll case, and finally takes the ep_get() reference that pairs
with ep_remove()'s ep_put() in ep_insert()'s error paths. On failure
it frees the epi and decrements epoll_watches to match
ep_alloc_epitem().

ep_insert()'s remaining body is the rollback-via-ep_remove() chain
(reverse_path_check, EPOLLWAKEUP source creation, ep_ptable_queue_proc
allocation) and the ready-list / wake publication. Remove a few
stale comments that duplicated function-level documentation or
described obvious code.

No functional change; rollback boundaries unchanged -- every error
path after ep_register_epitem() still calls ep_remove(), preserving
the ep->refcount invariant that keeps ep_remove()'s WARN_ON_ONCE safe.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-10-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:28 +02:00
Christian Brauner
7de0309926
eventpoll: relocate KCMP helpers near compat syscalls
ep_find_tfd() and get_epoll_tfile_raw_ptr() are only used when
CONFIG_KCMP=y. They implement the lookup side of the kcmp(2)
KCMP_EPOLL_TFD query. The helpers currently live between ep_find()
and ep_poll_callback(), interrupting the run of hot-path code
(callback, wait-queue setup, path check, insert, modify, send_events,
poll) with a feature-gated block.

Move the #ifdef CONFIG_KCMP block next to #ifdef CONFIG_COMPAT, which
is also a peripheral ABI extension. Hot-path code becomes a
contiguous span, and the userspace-adjacent extensions cluster at the
end of the file just before eventpoll_init().

Pure code movement; diff is 44 removed and 44 added, all within one
block. No functional change.

Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Link: https://patch.msgid.link/20260424-work-epoll-rework-v1-9-249ed00a20f3@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-28 17:27:28 +02:00