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1,447,411 commits

Author SHA1 Message Date
Marco Crivellari
e40ad215ce driver core: replace use of system_unbound_wq with system_dfl_wq
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.

This lack of consistentcy cannot be addressed without refactoring the API.

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

Switch to using system_dfl_wq because system_unbound_wq is going away as part of
a workqueue restructuring.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://patch.msgid.link/20251114141618.172154-2-marco.crivellari@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:21:29 +01:00
Aaron Tomlin
cd22926af4 tick/nohz: Expose housekeeping CPUs in sysfs
Expose the current system-defined list of housekeeping CPUs in a new
sysfs file: /sys/devices/system/cpu/housekeeping.

This provides userspace performance tuning tools and resource managers
with a canonical, reliable method to accurately identify the cores
responsible for essential kernel maintenance workloads (RCU, timer
callbacks, and unbound workqueues). Currently, tooling must manually
calculate the housekeeping set by parsing complex kernel boot parameters
(like isolcpus= and nohz_full=) and system topology, which is prone to
error. This dedicated file simplifies the configuration of low-latency
workloads.

Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Link: https://patch.msgid.link/20251011012853.7539-2-atomlin@atomlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:20:51 +01:00
Aaron Tomlin
f10c23fa15 tick/nohz: avoid showing '(null)' if nohz_full= not set
In the context of CONFIG_NO_HZ_FULL=y, tick_nohz_full_mask (of type
cpumask_var_t) is initialised to 0. Memory is only allocated to the cpumask
data structure, in tick_nohz_full_setup(), when Linux kernel boot-time
parameter "nohz_full=" is correctly specified (see housekeeping_setup()).
If "nohz_full=" is not set and an attempt is made to read
/sys/devices/system/cpu/nohz_full, '(null)' can be displayed:

    ❯ cat /sys/devices/system/cpu/nohz_full
    (null)

This patch changes the output to print a newline (or 0x0A) instead of
'(null)', making it consistent with print_cpus_isolated() behaviour.

Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Link: https://patch.msgid.link/20251011011830.6670-3-atomlin@atomlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:20:49 +01:00
Aaron Tomlin
76987bac71 sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
The /sys/devices/system/cpu/nohz_full file is a read-only attribute that
reports the CPUs configured for tickless operation (CONFIG_NO_HZ_FULL=y).

The current definition uses the generic DEVICE_ATTR macro, which
unnecessarily requires specifying the file mode (0444) and a NULL
store operation pointer.

This patch converts the definition to use the dedicated DEVICE_ATTR_RO
macro. This correctly expresses the read-only nature of the attribute,
removes the redundant mode field, and simplifies the code. As a related
cleanup, rename the show function from print_cpus_nohz_full() to the
standard nohz_full_show() for consistency with common sysfs attribute
naming conventions.

Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Link: https://patch.msgid.link/20251011011830.6670-2-atomlin@atomlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:20:49 +01:00
Will Rosenberg
382b1e8f30 kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
There exists a memory leak of kernfs_iattrs contained as an element
of kernfs_node allocated in __kernfs_new_node(). __kernfs_setattr()
allocates kernfs_iattrs as a sub-object, and the LSM security check
incorrectly errors out and does not free the kernfs_iattrs sub-object.

Make an additional error out case that properly frees kernfs_iattrs if
security_kernfs_init_security() fails.

Fixes: e19dfdc83b ("kernfs: initialize security of newly created nodes")
Co-developed-by: Oliver Rosenberg <olrose55@gmail.com>
Signed-off-by: Oliver Rosenberg <olrose55@gmail.com>
Signed-off-by: Will Rosenberg <whrosenb@asu.edu>
Link: https://patch.msgid.link/20251125151332.2010687-1-whrosenb@asu.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:19:11 +01:00
Jane Chu
2467f9928c fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
On an ARM64 A1 system, it's possible to have physical memory span
up to the 64T boundary, like below

$ lsmem -b -r -n -o range,size
0x0000000080000000-0x00000000bfffffff 1073741824
0x0000080000000000-0x000008007fffffff 2147483648
0x00000800c0000000-0x0000087fffffffff 546534588416
0x0000400000000000-0x00004000bfffffff 3221225472
0x0000400100000000-0x0000407fffffffff 545460846592

So it's time to extend /sys/kernel/mm/page_idle/bitmap to be able
to account for >2G number of pages, by raising the kernfs file size
limit.

Signed-off-by: Jane Chu <jane.chu@oracle.com>
Link: https://patch.msgid.link/20251111202606.1505437-1-jane.chu@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:18:13 +01:00
Raag Jadav
d3d25f430c mod_devicetable: Bump auxiliary_device_id name size
We have an upcoming driver named "intel_ehl_pse_io". This creates an
auxiliary child device for it's GPIO sub-functionality, which matches
against "intel_ehl_pse_io.gpio-elkhartlake" and overshoots the current
maximum limit of 32 bytes for auxiliary device id string. Bump the size
to 40 bytes to satisfy such cases.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Link: https://patch.msgid.link/20251106052838.433673-1-raag.jadav@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:17:37 +01:00
Thomas Weißschuh
71464949b1 sysfs: simplify attribute definition macros
Define the macros in terms of each other.
This makes them easier to understand and also will make it easier to
implement the transition machinery for 'const struct attribute'.

__ATTR_RO_MODE() can't be implemented in terms of __ATTR() as not all
attributes have a .store callback. The same issue theoretically exists
for __ATTR_WO(), but practically that does not occur today.

Reorder __ATTR_RO() below __ATTR_RO_MODE() to keep the order of the
macro definition consistent with respect to each other.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-7-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
2d76fdc1c9 samples/kobject: constify 'struct foo_attribute'
Showcase and test the new 'struct attribute' constification facilities.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-6-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
c301a2e2d7 samples/kobject: add is_visible() callback to attribute group
There was no example for the is_visible() callback so far.

It will also become an example and test for the constification of
'struct attribute' later.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-5-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
7dd9fdb493 sysfs: attribute_group: enable const variants of is_visible()
When constifying instances of struct attribute, for consistency the
corresponding .is_visible() callback should be adapted, too.
Introduce a temporary transition mechanism until all callbacks are
converted.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-4-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
02ac5335a5 sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
For the constification phase of 'struct attribute' various callback
struct members will need to exist in both const and non-const variants.
Keeping both members in a union avoids memory and CPU overhead but will
be detected and trapped by Control Flow Integrity (CFI). By deciding
between a struct and a union depending whether CFI is enabled, most
configurations can avoid this overhead. Code using these callbacks will
still need to be updated to handle both members explicitly.
In the union case the compiler will recognize that testing for one union
member is enough and optimize away the code for the other one.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-3-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
964c93b1ee sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
To ease the constification process of 'struct attribute', transparently
handle the const pointers in ATTRIBUTE_GROUPS(). A cast is used instead
of assigning to .attrs_new as it keeps the macro smaller. As both
members are aliased to each other the result is identical.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-2-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:35 +01:00
Thomas Weißschuh
f85d90dd8d sysfs: attribute_group: allow registration of const attribute
To be able to constify instances of struct attribute it has to be
possible to add them to struct attribute_group. The current type of the
attrs member however is not compatible with that. Introduce a union that
allows registration of both const and non-const attributes to enable a
piecewise transition. As both union member types are compatible no
logic needs to be adapted.

Technically it is now possible register a const struct attribute and
receive it as mutable pointer in the callbacks. This is a soundness
issue.  But this same soundness issue already exists today in
sysfs_create_file(). Also the struct definition and callback
implementation are always closely linked and are meant to be moved to
const in lockstep.

Similar to commit 906c508afd ("sysfs: attribute_group: allow
registration of const bin_attribute")

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-1-ea7d745acff4@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:16:34 +01:00
Clint George
cbe1d77ed8 hangcheck-timer: fix coding style spacing
Fix minor styling issues for proper compliance to the kernel coding
style.

Signed-off-by: Clint George <clintbgeorge@gmail.com>
Link: https://patch.msgid.link/20251111151340.9162-4-clintbgeorge@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:11:15 +01:00
Clint George
e03a2f7df7 hangcheck-timer: Replace %Ld with %lld
Replace non-standard %Ld with %lld to ensure compliance with the kernel
coding style and potential formatting issues.

Signed-off-by: Clint George <clintbgeorge@gmail.com>
Link: https://patch.msgid.link/20251111151340.9162-3-clintbgeorge@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:11:15 +01:00
Clint George
75d19e3686 hangcheck-timer: replace printk(KERN_CRIT) with pr_crit
Replace printk(KERN_CRIT ...) with pr_crit(...) and printk() with
pr_debug(). The change aims to make logging more consistent and
readable.

Signed-off-by: Clint George <clintbgeorge@gmail.com>
Link: https://patch.msgid.link/20251111151340.9162-2-clintbgeorge@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:11:15 +01:00
Yaxing Guo
3397c3cd85 uio: Add SVA support for PCI devices via uio_pci_generic_sva.c
This patch introduces a new UIO driver, uio_pci_generic_sva, which
extends the functionality of uio_pci_generic by adding support for
Shared Virtual Addressing (SVA) when IOMMU is enabled in the system.

The key enhancement allows PCI devices to directly use user-space virtual
addresses for DMA operations, eliminating the need for bounce buffers or
explicit IOVA mapping. This is achieved by leveraging the kernel's IOMMU-SVA
subsystem, including process address space attachment, page fault handling,
and shared context management between CPU and device.

With this driver, userspace applications can perform zero-copy DMA using
native pointers:

   void *addr = malloc(N);
   set_dma_addr((uint64_t)addr);  // Passing user VA directly
   start_dma();

The device can now access 'addr' through the IOMMU's PASID-based translation,
provided that the underlying IOMMU hardware (e.g., Intel VT-d 3.1+, AMD-Vi,
ARM SMMU, RISCV IOMMU) and platform support SVA.

Dependencies:
- CONFIG_IOMMU_SVA must be enabled.
- The platform must support PRI (Page Request Interface) and PASID.
- Device drivers/userspace must handle page faults if demand-paging is used.

The implementation reuses core logic from uio_pci_generic.c while adding
PASID setting, and integration with the IOMMU SVA APIs.

Also, add a read-only sysfs attribute 'pasid' to expose the Process Address
Space ID assigned by IOMMU driver when binding an SVA-enabled device.
For details, refer to the ABI documentation for uio_pci_sva driver sysfs attribute
(Documentation/ABI/testing/sysfs-driver-uio_pci_sva-pasid).

Signed-off-by: Yaxing Guo <guoyaxing@bosc.ac.cn>
Link: https://patch.msgid.link/20250926095828.506-1-guoyaxing@bosc.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:10:39 +01:00
Srinivas Kandagatla
4d4e746aa9 dt-bindings: slimbus: fix warning from example
Fix below warnings generated dt_bindings_check for examples in the
bindings.

Documentation/devicetree/bindings/slimbus/slimbus.example.dtb:
slim@28080000 (qcom,slim-ngd-v1.5.0): 'audio-codec@1,0' does not match
any of the regexes: '^pinctrl-[0-9]+$', '^slim@[0-9a-f]+$'
        from schema $id:
http://devicetree.org/schemas/slimbus/qcom,slim-ngd.yaml#
Documentation/devicetree/bindings/slimbus/slimbus.example.dtb:
slim@28080000 (qcom,slim-ngd-v1.5.0): #address-cells: 1 was expected
        from schema $id:
http://devicetree.org/schemas/slimbus/qcom,slim-ngd.yaml#
Documentation/devicetree/bindings/slimbus/slimbus.example.dtb:
slim@28080000 (qcom,slim-ngd-v1.5.0): 'dmas' is a required property
        from schema $id:
http://devicetree.org/schemas/slimbus/qcom,slim-ngd.yaml#
Documentation/devicetree/bindings/slimbus/slimbus.example.dtb:
slim@28080000 (qcom,slim-ngd-v1.5.0): 'dma-names' is a required
property
        from schema $id:
http://devicetree.org/schemas/slimbus/qcom,slim-ngd.yaml#

Fixes: 7cbba32a2d ("slimbus: qcom: remove unused qcom controller driver")
Cc: stable <stable@kernel.org>
Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20251114110505.143105-1-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:10:25 +01:00
Ma Ke
6d5925b667 intel_th: Fix error handling in intel_th_output_open
intel_th_output_open() calls bus_find_device_by_devt() which
internally increments the device reference count via get_device(), but
this reference is not properly released in several error paths. When
device driver is unavailable, file operations cannot be obtained, or
the driver's open method fails, the function returns without calling
put_device(), leading to a permanent device reference count leak. This
prevents the device from being properly released and could cause
resource exhaustion over time.

Found by code review.

Cc: stable <stable@kernel.org>
Fixes: 39f4034693 ("intel_th: Add driver infrastructure for Intel(R) Trace Hub devices")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Link: https://patch.msgid.link/20251112091723.35963-1-make24@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:10:03 +01:00
Christophe JAILLET
43cd4b634e misc: rp1: Fix an error handling path in rp1_probe()
When DT is used to get the reference of 'rp1_node', it should be released
when not needed anymore, otherwise it is leaking.

In such a case, add the missing of_node_put() call at the end of the probe,
as already done in the error handling path.

Fixes: 49d63971f9 ("misc: rp1: RaspberryPi RP1 misc driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andrea della Porta <andrea.porta@suse.com>
Link: https://patch.msgid.link/9bc1206de787fa86384f3e5ba0a8027947bc00ff.1762585959.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:49 +01:00
Marco Crivellari
85e8378958 char: xillybus: add WQ_UNBOUND to alloc_workqueue users
Currently if a user enqueues a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistency cannot be addressed without refactoring the API.

alloc_workqueue() treats all queues as per-CPU by default, while unbound
workqueues must opt-in via WQ_UNBOUND.

This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

This change adds the WQ_UNBOUND flag to explicitly request
alloc_workqueue() to be unbound, because this specific workload has no
benefit being per-cpu.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.

Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Acked-by: Eli Billauer <eli.billauer@gmail.com>
Link: https://patch.msgid.link/20251107163755.356187-1-marco.crivellari@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:43 +01:00
Vivek BalachandharTN
ef48f0f19e misc: bh1770glc: use pm_runtime_resume_and_get() in power_state_store
pm_runtime_get_sync() may increment the runtime PM usage count even if the
resume fails, which requires an explicit pm_runtime_put_noidle() to balance
it. This driver ignored the return value, risking a usage-count leak on
resume failure.

Replace it with pm_runtime_resume_and_get(), which returns 0 on success and
a negative errno on failure, and only increments the usage count on success.
This simplifies the error path and avoids possible leaks. Also check for
errors explicitly with `if (ret < 0)`.

Signed-off-by: Vivek BalachandharTN <vivek.balachandhar@gmail.com>
Link: https://patch.msgid.link/20251030120022.239951-1-vivek.balachandhar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:37 +01:00
Dan Carpenter
05d36a5931 misc: cb710: Fix a NULL vs IS_ERR() check in probe()
The pcim_iomap_region() function never returns NULL, it returns error
pointers.  Update the checking to match.

Fixes: b91c13534a ("misc: cb710: Replace deprecated PCI functions")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/aQITFDPyuzjNN4GN@stanley.mountain
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:34 +01:00
Thomas Richard (TI.com)
4863cb2b0f mux: mmio: Add suspend and resume support
The status of each mux is read during suspend and stored in the private
memory of the mux_chip.
Then the state is restored during the resume.

Reviewed-by: Andrew Davis <afd@ti.com>
Signed-off-by: Thomas Richard (TI.com) <thomas.richard@bootlin.com>
Link: https://patch.msgid.link/20251013-mux-mmio-resume-support-v5-1-de9467ceb2b2@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:30 +01:00
Randy Dunlap
f0fdaa4ad5 virt: acrn: split acrn_mmio_dev_res out of acrn_mmiodev
Add struct acrn_mmio_dev_res before struct acrn_mmio_dev.
The former is used in the latter and breaking them up provides
better kernel-doc documentation for the struct members.

Suggested-by: Fei Li <fei1.li@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Fei Li <fei1.li@intel.com>
Link: https://patch.msgid.link/20251028040409.868254-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 15:09:24 +01:00
Christian Brauner
f403e1206b
Merge patch series "fs: tidy up step_into() & friends before inlining"
Cleanup step_into() and walk_component() and inline them both.

* patches from https://patch.msgid.link/20251120003803.2979978-1-mjguzik@gmail.com:
  fs: inline step_into() and walk_component()
  fs: tidy up step_into() & friends before inlining

Link: https://patch.msgid.link/20251120003803.2979978-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:52:07 +01:00
Mateusz Guzik
177fdbae39
fs: inline step_into() and walk_component()
The primary consumer is link_path_walk(), calling walk_component() every
time which in turn calls step_into().

Inlining these saves overhead of 2 function calls per path component,
along with allowing the compiler to do better job optimizing them in place.

step_into() had absolutely atrocious assembly to facilitate the
slowpath. In order to lessen the burden at the callsite all the hard
work is moved into step_into_slowpath() and instead an inline-able
fastpath is implemented for rcu-walk.

The new fastpath is a stripped down step_into() RCU handling with a
d_managed() check from handle_mounts().

Benchmarked as follows on Sapphire Rapids:
1. the "before" was a kernel with not-yet-merged optimizations (notably
   elision of calls to security_inode_permission() and marking ext4
   inodes as not having acls as applicable)
2. "after" is the same + the prep patch + this patch
3. benchmark consists of issuing 205 calls to access(2) in a loop with
   pathnames lifted out of gcc and the linker building real code, most
   of which have several path components and 118 of which fail with
   -ENOENT.

Result in terms of ops/s:
before:	21619
after:	22536 (+4%)

profile before:
  20.25%  [kernel]                  [k] __d_lookup_rcu
  10.54%  [kernel]                  [k] link_path_walk
  10.22%  [kernel]                  [k] entry_SYSCALL_64
   6.50%  libc.so.6                 [.] __GI___access
   6.35%  [kernel]                  [k] strncpy_from_user
   4.87%  [kernel]                  [k] step_into
   3.68%  [kernel]                  [k] kmem_cache_alloc_noprof
   2.88%  [kernel]                  [k] walk_component
   2.86%  [kernel]                  [k] kmem_cache_free
   2.14%  [kernel]                  [k] set_root
   2.08%  [kernel]                  [k] lookup_fast

after:
  23.38%  [kernel]                  [k] __d_lookup_rcu
  11.27%  [kernel]                  [k] entry_SYSCALL_64
  10.89%  [kernel]                  [k] link_path_walk
   7.00%  libc.so.6                 [.] __GI___access
   6.88%  [kernel]                  [k] strncpy_from_user
   3.50%  [kernel]                  [k] kmem_cache_alloc_noprof
   2.01%  [kernel]                  [k] kmem_cache_free
   2.00%  [kernel]                  [k] set_root
   1.99%  [kernel]                  [k] lookup_fast
   1.81%  [kernel]                  [k] do_syscall_64
   1.69%  [kernel]                  [k] entry_SYSCALL_64_safe_stack

While walk_component() and step_into() of course disappear from the
profile, the link_path_walk() barely gets more overhead despite the
inlining thanks to the fast path added and while completing more walks
per second.

I did not investigate why overhead grew a lot on __d_lookup_rcu().

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251120003803.2979978-2-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:52:02 +01:00
Mateusz Guzik
9d2a6211a7
fs: tidy up step_into() & friends before inlining
Symlink handling is already marked as unlikely and pushing out some of
it into pick_link() reduces register spillage on entry to step_into()
with gcc 14.2.

The compiler needed additional convincing that handle_mounts() is
unlikely to fail.

At the same time neither clang nor gcc could be convinced to tail-call
into pick_link().

While pick_link() takes an address of stack-based object as an argument
(which definitely prevents the optimization), splitting it into separate
<dentry, mount> tuple did not help. The issue persists even when
compiled without stack protector. As such nothing was done about this
for the time being to not grow the diff.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251120003803.2979978-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:52:02 +01:00
Christian Brauner
1ed45a4ddc
Merge patch series "re-enable IOCB_NOWAIT writes to files v2"
Christoph Hellwig <hch@lst.de> says:

[Fix] the layering bypass in btrfs when updating timestamps on device
files for devices removed from btrfs usage, and FMODE_NOCMTIME handling
in the VFS now that nfsd started using it.  Note that I'm still not sure
that nfsd usage is fully correct for all file systems, as only XFS
explicitly supports FMODE_NOCMTIME, but at least the generic code does
the right thing now.

* patches from https://patch.msgid.link/20251120064859.2911749-1-hch@lst.de:
  orangefs: use inode_update_timestamps directly
  btrfs: fix the comment on btrfs_update_time
  btrfs: use vfs_utimes to update file timestamps
  fs: export vfs_utimes
  fs: lift the FMODE_NOCMTIME check into file_update_time_flags
  fs: refactor file timestamp update logic

Link: https://patch.msgid.link/20251120064859.2911749-1-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:17 +01:00
Christoph Hellwig
eff094a58d
orangefs: use inode_update_timestamps directly
Orangefs has no i_version handling and __orangefs_setattr already
explicitly marks the inode dirty.  So instead of the using
the flags return value from generic_update_time, just call the
lower level inode_update_timestamps helper directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-7-hch@lst.de
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Christoph Hellwig
f981264ae7
btrfs: fix the comment on btrfs_update_time
Since commit e41f941a23 ("Btrfs: move over to use ->update_time") this
is not a copy of the high-level file_update_time helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-6-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Christoph Hellwig
ded9958704
btrfs: use vfs_utimes to update file timestamps
Btrfs updates the device node timestamps for block device special files
when it stop using the device.

Commit 8f96a5bfa1 ("btrfs: update the bdev time directly when closing")
switch that update from the correct layering to directly call the
low-level helper on the bdev inode.  This is wrong and got fixed in
commit 54fde91f52 ("btrfs: update device path inode time instead of
bd_inode") by updating the file system inode instead of the bdev inode,
but this kept the incorrect bypassing of the VFS interfaces and file
system ->update_times method.  Fix this by using the propet vfs_utimes
interface.

Fixes: 8f96a5bfa1 ("btrfs: update the bdev time directly when closing")
Fixes: 54fde91f52 ("btrfs: update device path inode time instead of bd_inode")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-5-hch@lst.de
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Christoph Hellwig
0139836652
fs: export vfs_utimes
This will be used to replace an incorrect direct call into
generic_update_time in btrfs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-4-hch@lst.de
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Christoph Hellwig
7f30e7a423
fs: lift the FMODE_NOCMTIME check into file_update_time_flags
FMODE_NOCMTIME used to be just a hack for the legacy XFS handle-based
"invisible I/O", but commit e5e9b24ab8 ("nfsd: freeze c/mtime updates
with outstanding WRITE_ATTRS delegation") started using it from
generic callers.

I'm not sure other file systems are actually read for this in general,
so the above commit should get a closer look, but for it to make any
sense, file_update_time needs to respect the flag.

Lift the check from file_modified_flags to file_update_time so that
users of file_update_time inherit the behavior and so that all the
checks are done in one place.

Fixes: e5e9b24ab8 ("nfsd: freeze c/mtime updates with outstanding WRITE_ATTRS delegation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-3-hch@lst.de
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Christoph Hellwig
3cd9a42f1b
fs: refactor file timestamp update logic
Currently the two high-level APIs use two helper functions to implement
almost all of the logic.  Refactor the two helpers and the common logic
into a new file_update_time_flags routine that gets the iocb flags or
0 in case of file_update_time passed so that the entire logic is
contained in a single function and can be easily understood and modified.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251120064859.2911749-2-hch@lst.de
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-26 14:50:10 +01:00
Haotian Zhang
e6df0f649c greybus: gb-beagleplay: Fix timeout handling in bootloader functions
wait_for_completion_timeout() returns the remaining jiffies
(at least 1) on success or 0 on timeout, but never negative
error codes. The current code incorrectly checks for negative
values, causing timeouts to be ignored and treated as success.

Check for a zero return value to correctly identify and
handle timeout events.

Fixes: 0cf7befa3e ("greybus: gb-beagleplay: Add firmware upload API")
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Link: https://patch.msgid.link/20251121064027.571-1-vulab@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:59 +01:00
Marco Crivellari
8c5d9488b9 greybus: add WQ_PERCPU to alloc_workqueue users
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

This change adds a new WQ_PERCPU flag to explicitly request
alloc_workqueue() to be per-cpu when WQ_UNBOUND has not been specified.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.

Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Reviewed-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251112152710.207577-1-marco.crivellari@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:53 +01:00
Jiri Slaby (SUSE)
00a925eee8 char/mwave: drop typedefs
typedefs are unnecessary here. They rather obfuscate the code than help.
So drop them and use the types directly.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-7-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:46 +01:00
Jiri Slaby (SUSE)
1c7e15b0e5 char/mwave: drop printk wrapper
PRINTK_ERROR() + KERN_ERR_MWAVE are just wrappers around printk() with
a prefix. Instead, pr_fmt() can be used. Drop the former and use the
latter.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:46 +01:00
Jiri Slaby (SUSE)
53688a9f37 char/mwave: remove printk tracing
The printk tracing makes the code hard to follow for no good benefit.
Everyone can use dynamic tracing and/or kprobes.

Drop this unreadable bloatware too.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:46 +01:00
Jiri Slaby (SUSE)
3b4df2320e char/mwave: remove unneeded fops
file_operations::{read/write/open/release} need not be defined. The core
code return proper values already (the same as the being removed ones).
So there is no need to preserve these just for tracing via printk.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:46 +01:00
Jiri Slaby (SUSE)
48e77862a7 char/mwave: remove MWAVE_FUTZ_WITH_OTHER_DEVICES ifdeffery
In mwave, a lot of code depends on the MWAVE_FUTZ_WITH_OTHER_DEVICES
macro. That can be defined in Makefile to compile this in.

1) The code is completely unreadable.
2) Recompiling the kernel to have this untested code compiled in is not
   a good idea.

Drop all this.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:45 +01:00
Jiri Slaby (SUSE)
3b4d1b226d char/mwave: remove dead code
In mwave, there is a lot of commented code for a long time. Drop it.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:40:45 +01:00
Lad Prabhakar
043cc03345
spi: dt-bindings: renesas,rzv2h-rspi: Document RZ/V2N SoC support
Document the RSPI controller on the Renesas RZ/V2N SoC. The block is
compatible with the RSPI implementation found on the RZ/V2H(P) family.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20251126131619.136605-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2025-11-26 13:33:20 +00:00
Alexandre Courbot
9906efa545 firmware_loader: make RUST_FW_LOADER_ABSTRACTIONS select FW_LOADER
The use of firmware_loader is an implementation detail of drivers rather
than a dependency. FW_LOADER is typically selected rather than depended
on; the Rust abstractions should do the same thing.

Fixes: de6582833d ("rust: add firmware abstractions")
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251106-b4-select-rust-fw-v3-1-771172257755@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:32:10 +01:00
Adam Quandour
1520007aa3 staging: gpib: Clean-up commented-out code
Remove unused code.

Signed-off-by: Adam Quandour <adam.quandour@gmail.com>
Link: https://patch.msgid.link/20251124192048.290425-1-adam.quandour@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:28:19 +01:00
Shengjiu Wang
73b97d46dd
ASoC: fsl_xcvr: clear the channel status control memory
memset_io() writes memory byte by byte with __raw_writeb() on the arm
platform if the size is word. but XCVR data RAM memory can't be accessed
with byte address, so with memset_io() the channel status control memory
is not really cleared, use writel_relaxed() instead.

Fixes: 2856448686 ("ASoC: fsl_xcvr: Add XCVR ASoC CPU DAI driver")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://patch.msgid.link/20251126064509.1900974-1-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2025-11-26 13:24:19 +00:00
Navaneeth K
ea39cd0e42 staging: rtl8723bs: remove custom FIELD_OFFSET macro
The custom FIELD_OFFSET macro is no longer used in the driver (replaced
by standard offsetof). Remove the definition.

Signed-off-by: Navaneeth K <knavaneeth786@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20251125112059.16913-6-knavaneeth786@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:21:02 +01:00
Navaneeth K
d82c5681df staging: rtl8723bs: replace FIELD_OFFSET usage with offsetof in rtw_mlme_ext.c
Replace usage of the custom FIELD_OFFSET macro with the standard
offsetof() macro in rtw_mlme_ext.c. This improves code readability
and uses the kernel's standard mechanism.

Signed-off-by: Navaneeth K <knavaneeth786@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20251125112059.16913-5-knavaneeth786@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26 14:21:02 +01:00