This reverts commit dc23806a7c ("driver core: enforce device_lock for
driver_match_device()") and commit 289b14592c ("driver core: fix
inverted "locked" suffix of driver_match_device()").
While technically correct, there is a major downside to this approach:
When a device is already present in the system and a driver is
registered on the same bus, we iterate over all devices registered on
this bus to see if one of them matches. If we come across an already
bound one where the corresponding driver crashed while holding the
device lock (e.g. in probe()) we can't make any progress anymore.
However, drivers are typically the least tested code in the kernel and
hence it is a case that is likely to happen regularly. Besides hurting
developer ergonomics, it potentially decreases chances of shutting
things down cleanly and obtaining logs in production environments as
well [1].
This came up in the context of a firewire bug, which only in combination
with the reverted commit, caused the machine to hang [2]. Additionally,
it was observed in [3].
Thus, revert commit dc23806a7c ("driver core: enforce device_lock for
driver_match_device()") and add a brief note clarifying that an
implementer of struct bus_type must not expect match() to be called with
the device lock held.
Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [1]
Link: https://lore.kernel.org/all/67f655bb-4d81-4609-b008-68d200255dd2@davidgow.net/ [2]
Link: https://lore.kernel.org/lkml/CALbr=LZ4v7N=tO1vgOsyj9AS+XuNbn6kG-QcF+PacdMjSo0iyw@mail.gmail.com/ [3]
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/driver-core/CAHk-=wgJ_L1C=HjcYJotg_zrZEmiLFJaoic+PWthjuQrutrfJw@mail.gmail.com/
Reviewed-by: Gui-Dong Han <hanguidong02@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/20260302002545.19389-1-dakr@kernel.org
[ Add additional Link: reference. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
When device_get_child_node_count() got split to the fwnode and device
respective APIs, the fwnode didn't inherit the ability to traverse over
the secondary fwnode. Hence any user, that switches from device to fwnode
API misses this feature. In particular, this was revealed by the commit
1490cbb9db ("device property: Split fwnode_get_child_node_count()")
that effectively broke the GPIO enumeration on Intel Galileo boards.
Fix this by moving the secondary lookup from device to fwnode API.
Note, in general no device_*() API should go into the depth of the fwnode
implementation.
Fixes: 114dbb4fa7 ("drivers property: When no children in primary, try secondary")
Cc: stable@vger.kernel.org
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Link: https://patch.msgid.link/20260210135822.47335-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
- Fix the handling of package-scope MSRs in the intel_rapl power
capping driver when called from the PMU subsystem and make it add all
package CPUs to the PMU cpumask to allow tools to read RAPL events
from any CPU in the package (Kuppuswamy Satharayananyan)
- Rework the invalid version check in the intel_rapl_tpmi power capping
driver to account for the fact that on partitioned systems, multiple
TPMI instances may exist per package, but RAPL registers are only
valid on one instance (Kuppuswamy Satharayananyan)
- Describe the new intel_idle.table command line option in the
admin-guide intel_idle documentation (Artem Bityutskiy)
- Fix a crash in the ladder cpuidle governor on systems with only one
(polling) idle state available by making the cpuidle core bypass the
governor in those cases and adjust the other existing governors to
that change (Aboorva Devarajan, Christian Loehle)
- Update kerneldoc comments for wake IRQ management functions that
have not been matching the code (Wang Jiayue)
-----BEGIN PGP SIGNATURE-----
iQFGBAABCAAwFiEEcM8Aw/RY0dgsiRUR7l+9nS/U47UFAmmWDssSHHJqd0Byand5
c29ja2kubmV0AAoJEO5fvZ0v1OO1D5wH/j5drstZAsRqL4IwWPWBry0vhKGwr0vu
f8/sRuiAm/dRpi0Ro5XDiJbR4ZBLDp+4dDBOsR47Ss9a+B57iCftzmXcx5QBzUid
75W41IQ182Z/aGFQpU2kUPoRuNTUSmpUGVeon+SW4U24nCDaxOl4c2n8lWzgiznS
oJEN6Y9JfYV+fnLoxWmwyniR9USp2UFXS7tugDBMX1e1+sfrNbAUyuEKCs6R6u65
O7GTr2kA9lcM/hONBbXXpZNhtm23Jj0YS77lsELXoR9YWXTPJVTKVXmD11wrbWvE
quYefGoWCNcxQG3lYfw2vLdKMT3OYeRaq+DT3+9odaooHOJ6f4FqAzQ=
=cjJd
-----END PGP SIGNATURE-----
Merge tag 'pm-7.0-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These are mostly fixes on top of the power management updates merged
recently in cpuidle governors, in the Intel RAPL power capping driver
and in the wake IRQ management code:
- Fix the handling of package-scope MSRs in the intel_rapl power
capping driver when called from the PMU subsystem and make it add
all package CPUs to the PMU cpumask to allow tools to read RAPL
events from any CPU in the package (Kuppuswamy Satharayananyan)
- Rework the invalid version check in the intel_rapl_tpmi power
capping driver to account for the fact that on partitioned systems,
multiple TPMI instances may exist per package, but RAPL registers
are only valid on one instance (Kuppuswamy Satharayananyan)
- Describe the new intel_idle.table command line option in the
admin-guide intel_idle documentation (Artem Bityutskiy)
- Fix a crash in the ladder cpuidle governor on systems with only one
(polling) idle state available by making the cpuidle core bypass
the governor in those cases and adjust the other existing governors
to that change (Aboorva Devarajan, Christian Loehle)
- Update kerneldoc comments for wake IRQ management functions that
have not been matching the code (Wang Jiayue)"
* tag 'pm-7.0-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpuidle: menu: Remove single state handling
cpuidle: teo: Remove single state handling
cpuidle: haltpoll: Remove single state handling
cpuidle: Skip governor when only one idle state is available
powercap: intel_rapl_tpmi: Remove FW_BUG from invalid version check
PM: sleep: wakeirq: Update outdated documentation comments
Documentation: PM: Document intel_idle.table command line option
powercap: intel_rapl: Expose all package CPUs in PMU cpumask
powercap: intel_rapl: Remove incorrect CPU check in PMU context
Core changes:
- Drop the unused devm_pinctrl_unregister() function.
- Move pretended generic pin control functionality out of the
core and into the Amlogic AM4 driver. We have something better
coming (hopefully).
New hardware support:
- Spacemit K3 (RISC-V) pin control support.
- Atmel AT91 PIO4 (ARM32) SAMA7D65 pin control support.
- Exynos9610 (ARM64) pin control support.
- Qualcomm Mahua TLMM (ARM64) pin control support.
- Microchip Polarfire MSSIO (RISC-V) pin control support.
- Ocelot LAN9645XF (multiplatform) pin control support.
Improvements:
- Using a few more guards for locking.
- Various nonurgent fixes and tweaks.
-----BEGIN PGP SIGNATURE-----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=lmwJ
-----END PGP SIGNATURE-----
Merge tag 'pinctrl-v7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"Core changes:
- Drop the unused devm_pinctrl_unregister() function
- Move pretended generic pin control functionality out of the core
and into the Amlogic AM4 driver. We have something better coming
(hopefully)
New hardware support:
- Spacemit K3 (RISC-V) pin control support
- Atmel AT91 PIO4 (ARM32) SAMA7D65 pin control support
- Exynos9610 (ARM64) pin control support
- Qualcomm Mahua TLMM (ARM64) pin control support
- Microchip Polarfire MSSIO (RISC-V) pin control support
- Ocelot LAN9645XF (multiplatform) pin control support
Improvements:
- Using a few more guards for locking
- Various nonurgent fixes and tweaks"
* tag 'pinctrl-v7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (73 commits)
pinctrl: generic: move function to amlogic-am4 driver
pinctrl: intel: Align Copyright note with corporate guidelines
pinctrl: mediatek: remove unused drv_offset field
pinctrl: canaan: k230: Fix NULL pointer dereference when parsing devicetree
pinctrl: single: fix refcount leak in pcs_add_gpio_func()
pinctrl: meson: amlogic-a4: Fix device node reference leak in bank helpers
pinctrl: qcom: sm8250-lpass-lpi: Fix i2s2_data_groups definition
pinctrl: core: Remove duplicate error messages
pinctrl: core: Simplify devm_pinctrl_*()
pinctrl: core: Remove unused devm_pinctrl_unregister()
dt-bindings: pinctrl: spacemit: fix drive-strength check warning
pinctrl: fix kismet issues with GENERIC_PINCTRL
pinctrl: tangier: Join tng_pinctrl_probe() into its wrapper
pinctrl: tangier: Remove duplicate error messages
pinctrl: lynxpoint: Remove duplicate error messages
pinctrl: cherryview: Remove duplicate error messages
pinctrl: baytrail: Remove duplicate error messages
pinctrl: intel: Remove duplicate error messages
pinctrl: equilibrium: Fix device node reference leak in pinbank_init()
dt-bindings: pinctrl: pinctrl-microchip-sgpio: add LAN969x
...
Usual driver updates (qla2xxx, mpi3mr, mpt3sas, ufs) plus assorted
cleanups and fixes. The biggest core change is the massive code
motion in the sd driver to remove forward declarations and the most
significant change is to enumify the queuecommand return.
Signed-off-by: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
-----BEGIN PGP SIGNATURE-----
iLgEABMIAGAWIQTnYEDbdso9F2cI+arnQslM7pishQUCaY4ljBsUgAAAAAAEAA5t
YW51MiwyLjUrMS4xMSwyLDImHGphbWVzLmJvdHRvbWxleUBoYW5zZW5wYXJ0bmVy
c2hpcC5jb20ACgkQ50LJTO6YrIWFlwEAr9nc1ntxH4UNPgFCVjKyAOa5IE+p5o5C
2lwQIufcihEBAORvI9KO6AoEK6v9TmMKZXoyVsDRFe79fQE5NwCjfAA3
=My8f
-----END PGP SIGNATURE-----
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"Usual driver updates (qla2xxx, mpi3mr, mpt3sas, ufs) plus assorted
cleanups and fixes.
The biggest core change is the massive code motion in the sd driver to
remove forward declarations and the most significant change is to
enumify the queuecommand return"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (78 commits)
scsi: csiostor: Fix dereference of null pointer rn
scsi: buslogic: Reduce stack usage
scsi: ufs: host: mediatek: Require CONFIG_PM
scsi: ufs: mediatek: Fix page faults in ufs_mtk_clk_scale() trace event
scsi: smartpqi: Fix memory leak in pqi_report_phys_luns()
scsi: mpi3mr: Make driver probing asynchronous
scsi: ufs: core: Flush exception handling work when RPM level is zero
scsi: efct: Use IRQF_ONESHOT and default primary handler
scsi: ufs: core: Use a host-wide tagset in SDB mode
scsi: qla2xxx: target: Add WQ_PERCPU to alloc_workqueue() users
scsi: qla2xxx: Add WQ_PERCPU to alloc_workqueue() users
scsi: qla4xxx: Add WQ_PERCPU to alloc_workqueue() users
scsi: mpi3mr: Driver version update to 8.17.0.3.50
scsi: mpi3mr: Fixed the W=1 compilation warning
scsi: mpi3mr: Record and report controller firmware faults
scsi: mpi3mr: Update MPI Headers to revision 39
scsi: mpi3mr: Use negotiated link rate from DevicePage0
scsi: mpi3mr: Avoid redundant diag-fault resets
scsi: mpi3mr: Rename log data save helper to reflect threaded/BH context
scsi: mpi3mr: Add module parameter to control threaded IRQ polling
...
- Bus:
- Ensure bus->match() is consistently called with the device lock held
- Improve type safety of bus_find_device_by_acpi_dev()
- Devtmpfs:
- Parse 'devtmpfs.mount=' boot parameter with kstrtoint() instead of
simple_strtoul()
- Avoid sparse warning by making devtmpfs_context_ops static
- IOMMU:
- Do not register the qcom_smmu_tbu_driver in arm_smmu_device_probe()
- MAINTAINERS:
- Add the new driver-core mailing list (driver-core@lists.linux.dev)
to all relevant entries
- Add missing tree location for "FIRMWARE LOADER (request_firmware)"
- Add driver-model documentation to the "DRIVER CORE" entry
- Add missing driver-core maintainers to the "AUXILIARY BUS" entry
- Misc:
- Change return type of attribute_container_register() to void; it has
always been infallible
- Do not export sysfs_change_owner(), sysfs_file_change_owner() and
device_change_owner()
- Move devres_for_each_res() from the public devres header to
drivers/base/base.h
- Do not use a static struct device for the faux bus; allocate it
dynamically
- Revocable:
- Patches for the revocable synchronization primitive have been
scheduled for v7.0-rc1, but have been reverted as they need some
more refinement
- Rust:
- Device:
- Support dev_printk on all device types, not just the core Device
struct; remove now-redundant .as_ref() calls in dev_* print calls
- Devres:
- Introduce an internal reference count in Devres<T> to avoid a
deadlock condition in case of (indirect) nesting
- DMA:
- Allow drivers to tune the maximum DMA segment size via
dma_set_max_seg_size()
- I/O:
- Introduce the concept of generic I/O backends to handle different
kinds of device shared memory through a common interface.
This enables higher-level concepts such as register abstractions,
I/O slices, and field projections to be built generically on top.
In a first step, introduce the Io, IoCapable<T>, and IoKnownSize
trait hierarchy for sharing a common interface supporting offset
validation and bound-checking logic between I/O backends.
- Refactor MMIO to use the common I/O backend infrastructure
- Misc:
- Add __rust_helper annotations to C helpers for inlining into Rust
code
- Use "kernel vertical" style for imports
- Replace kernel::c_str! with C string literals
- Update ARef imports to use sync::aref
- Use pin_init::zeroed() for struct auxiliary_device_id and debugfs
file_operations initialization
- Use LKMM atomic types in debugfs doc-tests
- Various minor comment and documentation fixes
- PCI:
- Implement PCI configuration space accessors using the common I/O
backend infrastructure
- Document pci::Bar device endianness assumptions
- SoC:
- Abstractions for struct soc_device and struct soc_device_attribute
- Sample driver for soc::Device
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQS2q/xV6QjXAdC7k+1FlHeO1qrKLgUCaY0JegAKCRBFlHeO1qrK
LtCjAQDeSqGuzQM6hkMjsUWbjdWyw0yrrXcOxhwIINTc7uCzogEA7JL00+eiKHYu
SV2Ckn6UnSQ14rpEaDIzgZdurZHGUAM=
=TL00
-----END PGP SIGNATURE-----
Merge tag 'driver-core-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core updates from Danilo Krummrich:
"Bus:
- Ensure bus->match() is consistently called with the device lock
held
- Improve type safety of bus_find_device_by_acpi_dev()
Devtmpfs:
- Parse 'devtmpfs.mount=' boot parameter with kstrtoint() instead of
simple_strtoul()
- Avoid sparse warning by making devtmpfs_context_ops static
IOMMU:
- Do not register the qcom_smmu_tbu_driver in arm_smmu_device_probe()
MAINTAINERS:
- Add the new driver-core mailing list (driver-core@lists.linux.dev)
to all relevant entries
- Add missing tree location for "FIRMWARE LOADER (request_firmware)"
- Add driver-model documentation to the "DRIVER CORE" entry
- Add missing driver-core maintainers to the "AUXILIARY BUS" entry
Misc:
- Change return type of attribute_container_register() to void; it
has always been infallible
- Do not export sysfs_change_owner(), sysfs_file_change_owner() and
device_change_owner()
- Move devres_for_each_res() from the public devres header to
drivers/base/base.h
- Do not use a static struct device for the faux bus; allocate it
dynamically
Revocable:
- Patches for the revocable synchronization primitive have been
scheduled for v7.0-rc1, but have been reverted as they need some
more refinement
Rust:
- Device:
- Support dev_printk on all device types, not just the core Device
struct; remove now-redundant .as_ref() calls in dev_* print
calls
- Devres:
- Introduce an internal reference count in Devres<T> to avoid a
deadlock condition in case of (indirect) nesting
- DMA:
- Allow drivers to tune the maximum DMA segment size via
dma_set_max_seg_size()
- I/O:
- Introduce the concept of generic I/O backends to handle
different kinds of device shared memory through a common
interface.
This enables higher-level concepts such as register
abstractions, I/O slices, and field projections to be built
generically on top.
In a first step, introduce the Io, IoCapable<T>, and IoKnownSize
trait hierarchy for sharing a common interface supporting offset
validation and bound-checking logic between I/O backends.
- Refactor MMIO to use the common I/O backend infrastructure
- Misc:
- Add __rust_helper annotations to C helpers for inlining into
Rust code
- Use "kernel vertical" style for imports
- Replace kernel::c_str! with C string literals
- Update ARef imports to use sync::aref
- Use pin_init::zeroed() for struct auxiliary_device_id and
debugfs file_operations initialization
- Use LKMM atomic types in debugfs doc-tests
- Various minor comment and documentation fixes
- PCI:
- Implement PCI configuration space accessors using the common I/O
backend infrastructure
- Document pci::Bar device endianness assumptions
- SoC:
- Abstractions for struct soc_device and struct soc_device_attribute
- Sample driver for soc::Device"
* tag 'driver-core-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (79 commits)
rust: devres: fix race condition due to nesting
rust: dma: add missing __rust_helper annotations
samples: rust: pci: Remove some additional `.as_ref()` for `dev_*` print
Revert "revocable: Revocable resource management"
Revert "revocable: Add Kunit test cases"
Revert "selftests: revocable: Add kselftest cases"
driver core: remove device_change_owner() export
sysfs: remove exports of sysfs_*change_owner()
driver core: disable revocable code from build
revocable: Add KUnit test for concurrent access
revocable: fix SRCU index corruption by requiring caller-provided storage
revocable: Add KUnit test for provider lifetime races
revocable: Fix races in revocable_alloc() using RCU
driver core: fix inverted "locked" suffix of driver_match_device()
rust: io: move MIN_SIZE and io_addr_assert to IoKnownSize
rust: pci: re-export ConfigSpace
rust: dma: allow drivers to tune max segment size
gpu: tyr: remove redundant `.as_ref()` for `dev_*` print
rust: auxiliary: use `pin_init::zeroed()` for device ID
rust: debugfs: use pin_init::zeroed() for file_operations
...
The comments claiming that dev_pm_*wake_irq*() helpers must be called
with dev->power.lock held and only from rpm_suspend/resume paths are not
accurate any mote, since pm_runtime_force_suspend/resume() call them
locklessly.
Update the comments to match the code.
Reported-by: Gui-Dong Han <hanguidong02@gmail.com>
Closes: https://lore.kernel.org/all/CAJZ5v0jN9fU9NdWqc-+F5hiSEP4JkR=_qcdGzzHtk1i5tvCDbQ@mail.gmail.com/
Fixes: c46a0d5ae4 ("PM: runtime: Extend support for wakeirq for force_suspend|resume")
Signed-off-by: Wang Jiayue <akaieurus@gmail.com>
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20260206092317.148885-1-akaieurus@gmail.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The main change here is the implementation of a mechanism for generating
register defaults via a callback rather than with a table in the driver.
This is useful for devices where there are large ranges of registers
with the same or generateable values, it allows us to have a small
amount of code instead of a larger amount of default data.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmmJ69gACgkQJNaLcl1U
h9BWFAf+ICxKNiAtJWfApq09F2WNdsI8qtc9PQuf6wi1cGLTE/mc+nC7LAljP/YQ
VqTJ67HEtKNlrmREdULKrn9rNhpZ24vPXr7VozScisR682muXqtoKhhiHfHfTKCt
47ptg4H3gppvsfXcPjxklsj3UCpv36nKZB9lKb18fTvDIwriwAU5e9P9JPtJ9fWc
IQo2KvZ4ENnEiEX6RN9jBukSvS/a97+UtG+i8c0qBaqLm9jGOz7fWfxGsSKtflIu
/JIqjsbGkA6Jo2Hz4rrIGi+anRPDNp0RFW6lSXrEWc2QU1aZgCXWEtBElxCbSYvc
JDeU1pnKKAlpItXj91IgcV7rv4LJjQ==
=sD3p
-----END PGP SIGNATURE-----
Merge tag 'regmap-v6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"The main change here is the implementation of a mechanism for
generating register defaults via a callback rather than with a table
in the driver.
This is useful for devices where there are large ranges of registers
with the same or generated values, it allows us to have a small amount
of code instead of a larger amount of default data"
* tag 'regmap-v6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regcache: Demote defaults readback from HW to debug print
regmap: add KUnit coverage for reg_default_cb callback
regmap: Add reg_default_cb callback for flat cache defaults
regmap: Enable REGMAP when REGMAP_SLIMBUS is enabled
ACPI:
- Add interrupt signalling support to the AGDI handler.
- Add Catalin and myself to the arm64 ACPI MAINTAINERS entry.
CPU features:
- Drop Kconfig options for PAN and LSE (these are detected at runtime).
- Add support for 64-byte single-copy atomic instructions (LS64/LS64V).
- Reduce MTE overhead when executing in the kernel on Ampere CPUs.
- Ensure POR_EL0 value exposed via ptrace is up-to-date.
- Fix error handling on GCS allocation failure.
CPU frequency:
- Add CPU hotplug support to the FIE setup in the AMU driver.
Entry code:
- Minor optimisations and cleanups to the syscall entry path.
- Preparatory rework for moving to the generic syscall entry code.
Hardware errata:
- Work around Spectre-BHB on TSV110 processors.
- Work around broken CMO propagation on some systems with the SI-L1
interconnect.
Miscellaneous:
- Disable branch profiling for arch/arm64/ to avoid issues with noinstr.
- Minor fixes and cleanups (kexec + ubsan, WARN_ONCE() instead of
WARN_ON(), reduction of boolean expression).
- Fix custom __READ_ONCE() implementation for LTO builds when operating
on non-atomic types.
Perf and PMUs:
- Support for CMN-600AE.
- Be stricter about supported hardware in the CMN driver.
- Support for DSU-110 and DSU-120.
- Support for the cycles event in the DSU driver (alongside the
dedicated cycles counter).
- Use IRQF_NO_THREAD instead of IRQF_ONESHOT in the cxlpmu driver.
- Use !bitmap_empty() as a faster alternative to bitmap_weight().
- Fix SPE error handling when failing to resume profiling.
Selftests:
- Add support for the FORCE_TARGETS option to the arm64 kselftests.
- Avoid nolibc-specific my_syscall() function.
- Add basic test for the LS64 HWCAP.
- Extend fp-pidbench to cover additional workload patterns.
-----BEGIN PGP SIGNATURE-----
iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAmmJ16QQHHdpbGxAa2Vy
bmVsLm9yZwAKCRC3rHDchMFjNFO0CACxYy5klTAdqB+RjhxSbibZ6mmch/mX3zLl
qBp0HeKuwSv+EWEblmr6KMrr/S5YjtEMboOC7GnmEdSeM6hucu5gPiEb7bIDQfbB
5KJXoUlN1C+7Na4CimfordWiHIZw2d7mTumJcnsqMo7XN83t+4yqs98sET7WRCy5
WUyqHH/dGZsGcsBMrRRO3UriHCpU425GE0jopF5OkwCs4dwyUVIV8SmZtK4Ovi3u
Kin75UYgeVum8A218oHosTfYTBt4p/cSdfVVv5f3P14Q7lIstyJR7ZDqepTP2XSJ
95W3nuMfOT1lx7f6pqvHc+4Ccl/+DQnbW1PWwv8f3nXAKVVMafWf
=3SfC
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"There's a little less than normal, probably due to LPC & Christmas/New
Year meaning that a few series weren't quite ready or reviewed in
time. It's still useful across the board, despite the only real
feature being support for the LS64 feature enabling 64-byte atomic
accesses to endpoints that support it.
ACPI:
- Add interrupt signalling support to the AGDI handler
- Add Catalin and myself to the arm64 ACPI MAINTAINERS entry
CPU features:
- Drop Kconfig options for PAN and LSE (these are detected at runtime)
- Add support for 64-byte single-copy atomic instructions (LS64/LS64V)
- Reduce MTE overhead when executing in the kernel on Ampere CPUs
- Ensure POR_EL0 value exposed via ptrace is up-to-date
- Fix error handling on GCS allocation failure
CPU frequency:
- Add CPU hotplug support to the FIE setup in the AMU driver
Entry code:
- Minor optimisations and cleanups to the syscall entry path
- Preparatory rework for moving to the generic syscall entry code
Hardware errata:
- Work around Spectre-BHB on TSV110 processors
- Work around broken CMO propagation on some systems with the SI-L1
interconnect
Miscellaneous:
- Disable branch profiling for arch/arm64/ to avoid issues with
noinstr
- Minor fixes and cleanups (kexec + ubsan, WARN_ONCE() instead of
WARN_ON(), reduction of boolean expression)
- Fix custom __READ_ONCE() implementation for LTO builds when
operating on non-atomic types
Perf and PMUs:
- Support for CMN-600AE
- Be stricter about supported hardware in the CMN driver
- Support for DSU-110 and DSU-120
- Support for the cycles event in the DSU driver (alongside the
dedicated cycles counter)
- Use IRQF_NO_THREAD instead of IRQF_ONESHOT in the cxlpmu driver
- Use !bitmap_empty() as a faster alternative to bitmap_weight()
- Fix SPE error handling when failing to resume profiling
Selftests:
- Add support for the FORCE_TARGETS option to the arm64 kselftests
- Avoid nolibc-specific my_syscall() function
- Add basic test for the LS64 HWCAP
- Extend fp-pidbench to cover additional workload patterns"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (43 commits)
perf/arm-cmn: Reject unsupported hardware configurations
perf: arm_spe: Properly set hw.state on failures
arm64/gcs: Fix error handling in arch_set_shadow_stack_status()
arm64: Fix non-atomic __READ_ONCE() with CONFIG_LTO=y
arm64: poe: fix stale POR_EL0 values for ptrace
kselftest/arm64: Raise default number of loops in fp-pidbench
kselftest/arm64: Add a no-SVE loop after SVE in fp-pidbench
perf/cxlpmu: Replace IRQF_ONESHOT with IRQF_NO_THREAD
arm64: mte: Set TCMA1 whenever MTE is present in the kernel
arm64/ptrace: Return early for ptrace_report_syscall_entry() error
arm64/ptrace: Split report_syscall()
arm64: Remove unused _TIF_WORK_MASK
kselftest/arm64: Add missing file in .gitignore
arm64: errata: Workaround for SI L1 downstream coherency issue
kselftest/arm64: Add HWCAP test for FEAT_LS64
arm64: Add support for FEAT_{LS64, LS64_V}
KVM: arm64: Enable FEAT_{LS64, LS64_V} in the supported guest
arm64: Provide basic EL2 setup for FEAT_{LS64, LS64_V} usage at EL0/1
KVM: arm64: Handle DABT caused by LS64* instructions on unsupported memory
KVM: arm64: Add documentation for KVM_EXIT_ARM_LDST64B
...
affinity of unbound kthreads (node or custom cpumask) against
housekeeping (CPU isolation) constraints and CPU hotplug events.
One crucial missing piece is the handling of cpuset: when an isolated
partition is created, deleted, or its CPUs updated, all the unbound
kthreads in the top cpuset become indifferently affine to _all_ the
non-isolated CPUs, possibly breaking their preferred affinity along
the way.
Solve this with performing the kthreads affinity update from cpuset to
the kthreads consolidated relevant code instead so that preferred
affinities are honoured and applied against the updated cpuset isolated
partitions.
The dispatch of the new isolated cpumasks to timers, workqueues and
kthreads is performed by housekeeping, as per the nice Tejun's
suggestion.
As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
from boot defined domain isolation (through isolcpus=) and cpuset
isolated partitions. Housekeeping cpumasks are now modifiable with a
specific RCU based synchronization. A big step toward making nohz_full=
also mutable through cpuset in the future.
-----BEGIN PGP SIGNATURE-----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=nWGh
-----END PGP SIGNATURE-----
Merge tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks
Pull kthread updates from Frederic Weisbecker:
"The kthread code provides an infrastructure which manages the
preferred affinity of unbound kthreads (node or custom cpumask)
against housekeeping (CPU isolation) constraints and CPU hotplug
events.
One crucial missing piece is the handling of cpuset: when an isolated
partition is created, deleted, or its CPUs updated, all the unbound
kthreads in the top cpuset become indifferently affine to _all_ the
non-isolated CPUs, possibly breaking their preferred affinity along
the way.
Solve this with performing the kthreads affinity update from cpuset to
the kthreads consolidated relevant code instead so that preferred
affinities are honoured and applied against the updated cpuset
isolated partitions.
The dispatch of the new isolated cpumasks to timers, workqueues and
kthreads is performed by housekeeping, as per the nice Tejun's
suggestion.
As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
from boot defined domain isolation (through isolcpus=) and cpuset
isolated partitions. Housekeeping cpumasks are now modifiable with a
specific RCU based synchronization. A big step toward making
nohz_full= also mutable through cpuset in the future"
* tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: (33 commits)
doc: Add housekeeping documentation
kthread: Document kthread_affine_preferred()
kthread: Comment on the purpose and placement of kthread_affine_node() call
kthread: Honour kthreads preferred affinity after cpuset changes
sched/arm64: Move fallback task cpumask to HK_TYPE_DOMAIN
sched: Switch the fallback task allowed cpumask to HK_TYPE_DOMAIN
kthread: Rely on HK_TYPE_DOMAIN for preferred affinity management
kthread: Include kthreadd to the managed affinity list
kthread: Include unbound kthreads in the managed affinity list
kthread: Refine naming of affinity related fields
PCI: Remove superfluous HK_TYPE_WQ check
sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated()
cpuset: Remove cpuset_cpu_is_isolated()
timers/migration: Remove superfluous cpuset isolation test
cpuset: Propagate cpuset isolation update to timers through housekeeping
cpuset: Propagate cpuset isolation update to workqueue through housekeeping
PCI: Flush PCI probe workqueue on cpuset isolated partition change
sched/isolation: Flush vmstat workqueues on cpuset isolated partition change
sched/isolation: Flush memcg workqueues on cpuset isolated partition change
cpuset: Update HK_TYPE_DOMAIN cpumask from cpuset
...
This reverts commit 62eb557580.
The revocable implementation uses two separate abstractions, struct
revocable_provider and struct revocable, in order to store the SRCU read
lock index which must be passed unaltered to srcu_read_unlock() in the
same context when a resource is no longer needed.
With the merged revocable API, multiple threads could however share the
same struct revocable and therefore potentially overwrite the SRCU index
of another thread which can cause the SRCU synchronisation in
revocable_provider_revoke() to never complete. [1]
An example revocable conversion of the gpiolib code also turned out to
be fundamentally flawed and could lead to use-after-free. [2]
An attempt to address both issues was quickly put together and merged,
but revocable is still fundamentally broken. [3]
Specifically, the latest design relies on RCU for storing a pointer to
the revocable provider, but since the resource can be shared by value
(e.g. as in the now reverted selftests) this does not work at all and
can also lead to use-after-free:
static void revocable_provider_release(struct kref *kref)
{
struct revocable_provider *rp = container_of(kref,
struct revocable_provider, kref);
cleanup_srcu_struct(&rp->srcu);
kfree_rcu(rp, rcu);
}
void revocable_provider_revoke(struct revocable_provider __rcu **rp_ptr)
{
struct revocable_provider *rp;
rp = rcu_replace_pointer(*rp_ptr, NULL, 1);
...
kref_put(&rp->kref, revocable_provider_release);
}
int revocable_init(struct revocable_provider __rcu *_rp,
struct revocable *rev)
{
struct revocable_provider *rp;
...
scoped_guard(rcu) {
rp = rcu_dereference(_rp);
if (!rp)
return -ENODEV;
if (!kref_get_unless_zero(&rp->kref))
return -ENODEV;
}
...
}
producer:
priv->rp = revocable_provider_alloc(&priv->res);
// pass priv->rp by value to consumer
revocable_provider_revoke(&priv->rp);
consumer:
struct revocable_provider __rcu *rp = filp->private_data;
struct revocable *rev;
revocable_init(rp, &rev);
as _rp would still be non-NULL in revocable_init() regardless of whether
the producer has revoked the resource and set its pointer to NULL.
Essentially revocable still relies on having a pointer to reference
counted driver data which holds the revocable provider, which makes all
the RCU protection unnecessary along with most of the current revocable
design and implementation.
As the above shows, and as has been pointed out repeatedly elsewhere,
these kind of issues are not something that should be addressed
incrementally. [4]
Revert the revocable implementation until a redesign has been proposed
and evaluated properly.
Link: https://lore.kernel.org/all/20260124170535.11756-4-johan@kernel.org/ [1]
Link: https://lore.kernel.org/all/aXT45B6vLf9R3Pbf@hovoldconsulting.com/ [2]
Link: https://lore.kernel.org/all/20260129143733.45618-1-tzungbi@kernel.org/ [3]
Link: https://lore.kernel.org/all/aXobzoeooJqxMkEj@hovoldconsulting.com/ [4]
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260204142849.22055-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit cd7693419b.
The new revocable functionality is fundamentally broken and at a minimum
needs to be redesigned.
Drop the revocable Kunit tests to allow the implementation to be reverted.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260204142849.22055-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function, device_change_owner() is exported for modules to use,
but there are no in-kernel users of it, so remove the export to prevent
out-of-tree code from thinking this is a safe function to call.
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Link: https://patch.msgid.link/2026020543-molar-childcare-af20@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge updates related to system suspend and hibernation for
6.20-rc1/7.0-rc1:
- Stop flagging the PM runtime workqueue as freezable to avoid system
suspend and resume deadlocks in subsystems that assume asynchronous
runtime PM to work during system-wide PM transitions (Rafael Wysocki)
- Drop redundant NULL pointer checks before acomp_request_free() from
the hibernation code handling image saving (Rafael Wysocki)
- Update wakeup_sources_walk_start() to handle empty lists of wakeup
sources as appropriate (Samuel Wu)
- Make dev_pm_clear_wake_irq() check the power.wakeirq value under
power.lock to avoid race conditions (Gui-Dong Han)
- Avoid bit field races related to power.work_in_progress in the core
device suspend code (Xuewen Yan)
* pm-sleep:
PM: sleep: core: Avoid bit field races related to work_in_progress
PM: sleep: wakeirq: harden dev_pm_clear_wake_irq() against races
PM: wakeup: Handle empty list in wakeup_sources_walk_start()
PM: hibernate: Drop NULL pointer checks before acomp_request_free()
PM: sleep: Do not flag runtime PM workqueue as freezable
The revocable code is still under active discussion, and there is no
in-kernel users of it. So disable it from the build for now so that no
one suffers from it being present in the tree, yet leave it in the
source tree so that others can easily test it by reverting this commit
and building off of it for future releases.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/2026020307-rimmed-dreamy-5a67@gregkh
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dev_pm_clear_wake_irq() currently uses a dangerous pattern where
dev->power.wakeirq is read and checked for NULL outside the lock.
If two callers invoke this function concurrently, both might see
a valid pointer and proceed. This could result in a double-free
when the second caller acquires the lock and tries to release the
same object.
Address this by removing the lockless check of dev->power.wakeirq.
Instead, acquire dev->power.lock immediately to ensure the check and
the subsequent operations are atomic. If dev->power.wakeirq is NULL
under the lock, simply unlock and return. This guarantees that
concurrent calls cannot race to free the same object.
Based on a quick scan of current users, I did not find an actual bug as
drivers seem to rely on their own synchronization. However, since
asynchronous usage patterns exist (e.g., in
drivers/net/wireless/ti/wlcore), I believe a race is theoretically
possible if the API is used less carefully in the future. This change
hardens the API to be robust against such cases.
Fixes: 4990d4fe32 ("PM / Wakeirq: Add automated device wake IRQ handling")
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://patch.msgid.link/20260203031943.1924-1-hanguidong02@gmail.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Make sure /sys/devices/system/cpu/isolated only prints what was passed
through the isolcpus= parameter before HK_TYPE_DOMAIN will also
integrate cpuset isolated partitions.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Add a test case to verify correct synchronization between concurrent
readers and a revocation.
The test setup involves:
1. Consumer 1 enters the critical section (SRCU read lock) and verifies
access to the resource.
2. Provider attempts to revoke the resource. This should block until
Consumer 1 releases the lock.
3. Consumer 2 attempts to enter the critical section while revocation
is pending. It should see the resource as revoked (NULL).
4. Consumer 1 exits, allowing the revocation to complete.
This ensures that the SRCU mechanism correctly enforces grace periods
and that new readers are properly prevented from accessing the resource
once revocation has begun.
A way to run the test:
$ ./tools/testing/kunit/kunit.py run \
--kconfig_add CONFIG_REVOCABLE_KUNIT_TEST=y \
--kconfig_add CONFIG_PROVE_LOCKING=y \
--kconfig_add CONFIG_DEBUG_KERNEL=y \
--kconfig_add CONFIG_DEBUG_INFO=y \
--kconfig_add CONFIG_DEBUG_INFO_DWARF5=y \
--kconfig_add CONFIG_KASAN=y \
--kconfig_add CONFIG_DETECT_HUNG_TASK=y \
--kconfig_add CONFIG_DEFAULT_HUNG_TASK_TIMEOUT="10" \
--arch=x86_64 --raw_output=all \
revocable_test
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-5-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct revocable handle stores the SRCU read-side index (idx) for
the duration of a resource access. If multiple threads share the same
struct revocable instance, they race on writing to the idx field,
corrupting the SRCU state and potentially causing unsafe unlocks.
Refactor the API to replace revocable_alloc()/revocable_free() with
revocable_init()/revocable_deinit(). This change requires the caller
to provide the storage for struct revocable.
By moving storage ownership to the caller, the API ensures that
concurrent users maintain their own private idx storage, eliminating
the race condition.
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/all/20260124170535.11756-4-johan@kernel.org/
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-4-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a test to verify that revocable_alloc() correctly handles race
conditions where the provider is being released.
The test covers three scenarios:
1. Allocating from a NULL provider.
2. Allocating from a provider that has been detached (pointer is NULL).
3. Allocating from a provider that is in the process of destruction
(refcount is 0), simulating a race between revocable_alloc() and
revocable_provider_release().
A way to run the test:
$ ./tools/testing/kunit/kunit.py run \
--kconfig_add CONFIG_REVOCABLE_KUNIT_TEST=y \
--kconfig_add CONFIG_PROVE_LOCKING=y \
--kconfig_add CONFIG_DEBUG_KERNEL=y \
--kconfig_add CONFIG_DEBUG_INFO=y \
--kconfig_add CONFIG_DEBUG_INFO_DWARF5=y \
--kconfig_add CONFIG_KASAN=y \
--kconfig_add CONFIG_DETECT_HUNG_TASK=y \
--kconfig_add CONFIG_DEFAULT_HUNG_TASK_TIMEOUT="10" \
--arch=x86_64 --raw_output=all \
revocable_test
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-3-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two race conditions when allocating a revocable instance:
1. After a struct revocable_provider is revoked, the caller might still
hold a dangling pointer to it. A subsequent call to
revocable_alloc() can trigger a use-after-free.
2. If revocable_provider_release() runs concurrently with
revocable_alloc(), the memory of struct revocable_provider can be
accessed during or after kfree().
To fix these:
- Manage the lifetime of struct revocable_provider using RCU. Annotate
pointers to it with __rcu and use kfree_rcu() for deallocation.
- Update revocable_alloc() to safely acquire a reference using RCU
primitives.
- Update revocable_provider_revoke() to take a double pointer (`**rp`).
It atomically NULLs out the caller's pointer before starting
revocation. This prevents the caller from holding a dangling pointer.
- Drop devm_revocable_provider_alloc(). The devm-managed model cannot
support the required double-pointer semantic for safe pointer nulling.
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/all/aXdy-b3GOJkzGqYo@hovoldconsulting.com/
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-2-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the case of an empty wakeup_sources list, wakeup_sources_walk_start()
will return an invalid but non-NULL address. This also affects wrappers
of the aforementioned function, like for_each_wakeup_source().
Update wakeup_sources_walk_start() to return NULL in case of an empty
list.
Fixes: b4941adb24 ("PM: wakeup: Add routine to help fetch wakeup source object.")
Signed-off-by: Samuel Wu <wusamuel@google.com>
[ rjw: Subject and changelog edits ]
Link: https://patch.msgid.link/20260124012133.2451708-2-wusamuel@google.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the current implementation driver_match_device() expects the device
lock to be held, while driver_match_device_locked() acquires the device
lock.
By convention it should be the other way around, hence swap the name of
both functions.
Fixes: dc23806a7c ("driver core: enforce device_lock for driver_match_device()")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://patch.msgid.link/20260131014211.12841-1-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Merge series from "Sheetal ." <sheetal@nvidia.com>:
This series adds a reg_default_cb callback for REGCACHE_FLAT to provide
defaults for registers not listed in reg_defaults. Defaults are loaded
eagerly during regcache init and the callback can use writeable_reg to
filter valid addresses and avoid holes.
Since commit 632e04739c ("clk: rs9: Fix suspend/resume"), the
clk-renesas-pcie-9series driver produces the following print in
kernel log on boot:
"
clk-renesas-pcie-9series 8-0068: No cache defaults, reading back from HW
"
This is caused by the presence of .num_reg_defaults_raw in its struct
regmap_config, without a matching .reg_defaults_raw table of built-in
register default values.
This configuration is valid, and causes the regcache code to read the
default register settings from the hardware, which is a valid behavior
for this particular chip. In fact, this configuration is more common
than configuration with .reg_defaults_raw built-in register defaults.
Do not warn about the read of default values being read from hardware,
as that is too strong and seems unnecessary, turn the warning into a
debug print.
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Link: https://patch.msgid.link/20260121234309.178391-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Add a flat-cache KUnit test that verifies reg_defaults are honored while
missing entries are populated via the reg_default_cb callback without
hardware reads. This exercises the new callback path added for
REGCACHE_FLAT defaults.
Test: ./tools/testing/kunit/kunit.py run regmap
Result:
======== reg_default_callback_populates_flat_cache ========
[PASSED] flat-default @0x0
[PASSED] flat-default fast I/O @0x0
[PASSED] flat-default @0x2001
==== [PASSED] reg_default_callback_populates_flat_cache ====
Signed-off-by: Sheetal <sheetal@nvidia.com>
Link: https://patch.msgid.link/20260123095346.1258556-5-sheetal@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit e062bdfdd6 ("regmap: warn users about uninitialized flat cache")
warns when REGCACHE_FLAT is used without full defaults. This causes
false positives on hardware where many registers reset to zero but are
not listed in reg_defaults, forcing drivers to maintain large tables
just to silence the warning.
Add a reg_default_cb() hook so drivers can supply defaults for registers
not present in reg_defaults when populating REGCACHE_FLAT. This keeps
the warning quiet for known zero-reset registers without bloating
tables. Provide a generic regmap_default_zero_cb() helper for drivers
that need zero defaults.
The hook is only used for REGCACHE_FLAT; the core does not
check readable/writeable access, so drivers must provide readable_reg/
writeable_reg callbacks and handle holes in the register map.
Signed-off-by: Sheetal <sheetal@nvidia.com>
Link: https://patch.msgid.link/20260123095346.1258556-3-sheetal@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCgA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAml2lQweHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG0dcH/2yLU3IKlHSSgEDL
Qq3oBuRK/zoVOdy+CM+TmTdl2d1LnBd8J547xFStB7kVGf5mEkdFZdHLBSHRnKDf
ia1SGec06kyLpRX6x5T6FsfwOhkBmVsp59X0coM57QWxxenybugtzPvDO2TQ8/G4
buixJI0jJVgwRwXNzWB4n2W6FxNGui2A7gEN2mjtvkM2t/aDkiDjEqB8ve0pZJX9
4EWhxOgRFzwWgkd/bY+4wgXVXEt3GtI+3VvNncRqLIO00A/AnZOYmH4S2RQUDszD
IbyDscYYxloZcZMDXc3PN2WgD9DCGKuP3GpJGsOHbl0DN6JkqI9nwGsOFZKGVOeF
vbajwPE=
=iAOa
-----END PGP SIGNATURE-----
Merge tag 'v6.19-rc7' into driver-core-next
We need the driver-core fixes in here as well to build on top of.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
- Always inline I/O and IRQ methods using build_assert!() to avoid
false positive build errors.
- Do not free the driver's device private data in I2C shutdown()
avoiding race conditions that can lead to UAF bugs.
- Drop the driver's device private data after the driver has been
fully unbound from its device to avoid UAF bugs from &Device<Bound>
scopes, such as IRQ callbacks.
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQS2q/xV6QjXAdC7k+1FlHeO1qrKLgUCaXTJdAAKCRBFlHeO1qrK
Lqt/AQDN7X8D6ABCPpYVZ0KKZZulLXjmv52CqtXc1IHBuergCgD/TEOu+t41amVb
EkSO6/yN/NwMP0+eEF+XT1ybM3CYDQI=
=8bg5
-----END PGP SIGNATURE-----
Merge tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core fixes from Danilo Krummrich:
- Always inline I/O and IRQ methods using build_assert!() to avoid
false positive build errors
- Do not free the driver's device private data in I2C shutdown()
avoiding race conditions that can lead to UAF bugs
- Drop the driver's device private data after the driver has been
fully unbound from its device to avoid UAF bugs from &Device<Bound>
scopes, such as IRQ callbacks
* tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
rust: driver: drop device private data post unbind
rust: driver: add DriverData type to the DriverLayout trait
rust: driver: add DEVICE_DRIVER_OFFSET to the DriverLayout trait
rust: driver: introduce a DriverLayout trait
rust: auxiliary: add Driver::unbind() callback
rust: i2c: do not drop device private data on shutdown()
rust: irq: always inline functions using build_assert with arguments
rust: io: always inline functions using build_assert with arguments
devres_for_each_res() is only used by .../firmware_loader/main.c, which
already includes base.h.
The usage of devres_for_each_res() by code outside of driver-core is
questionable, hence move it to base.h.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/20260119162920.77189-1-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
When allocating a revocable provider via revocable_provider_alloc(),
there is no revocable consumers (i.e., RCU readers) yet. Remove the
redundant synchronize_srcu() call to save cycles.
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260121040204.2699886-1-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pinctrl_bind_pins() is only used by driver core (as it should). Move it
out of the public header into base.h.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Linus Walleij <linusw@kernel.org>
Replace simple_strtoul() with the recommended kstrtoint() for parsing
the 'devtmpfs.mount=' boot parameter. Unlike simple_strtoul(), which
returns an unsigned long, kstrtoint() converts the string directly to
int and avoids implicit casting.
Check the return value of kstrtoint() and reject invalid values. This
adds error handling while preserving behavior for existing values, and
removes use of the deprecated simple_strtoul() helper. The current code
silently sets 'mount_dev = 0' if parsing fails, instead of leaving the
default value (IS_ENABLED(CONFIG_DEVTMPFS_MOUNT)) unchanged.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Link: https://patch.msgid.link/20251220125930.76836-2-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 'devtmpfs_context_ops' object is not exported outside the
devtmpfs.c file nor defined anywhere for use outside. Make this
static to remove the following sparse warning:
drivers/base/devtmpfs.c:88:30: warning: symbol 'devtmpfs_context_ops' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Link: https://patch.msgid.link/20260116150745.1330145-1-ben.dooks@codethink.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Kunit test cases for the revocable API.
The test cases cover the following scenarios:
- Basic: Verifies that a consumer can successfully access the resource
provided via the provider.
- Revocation: Verifies that after the provider revokes the resource,
the consumer correctly receives a NULL pointer on a subsequent access.
- Try Access Macro: Same as "Revocation" but uses the
REVOCABLE_TRY_ACCESS_WITH() and REVOCABLE_TRY_ACCESS_SCOPED().
A way to run the test:
$ ./tools/testing/kunit/kunit.py run \
--kconfig_add CONFIG_REVOCABLE_KUNIT_TEST=y \
revocable_test
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260116080235.350305-3-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some resources can be removed asynchronously, for example, resources
provided by a hot-pluggable device like USB. When holding a reference
to such a resource, it's possible for the resource to be removed and
its memory freed, leading to use-after-free errors on subsequent access.
The "revocable" mechanism addresses this by establishing a weak reference
to a resource that might be freed at any time. It allows a resource
consumer to safely attempt to access the resource, guaranteeing that the
access is valid for the duration of its use, or it fails safely if the
resource has already been revoked.
The implementation uses a provider/consumer model built on Sleepable
RCU (SRCU) to guarantee safe memory access:
- A resource provider, such as a driver for a hot-pluggable device,
allocates a struct revocable_provider and initializes it with a pointer
to the resource.
- A resource consumer that wants to access the resource allocates a
struct revocable which acts as a handle containing a reference to the
provider.
- To access the resource, the consumer uses revocable_try_access().
This function enters an SRCU read-side critical section and returns
the pointer to the resource. If the provider has already freed the
resource, it returns NULL. After use, the consumer calls
revocable_withdraw_access() to exit the SRCU critical section. The
REVOCABLE_TRY_ACCESS_WITH() and REVOCABLE_TRY_ACCESS_SCOPED() are
convenient helpers for doing that.
- When the provider needs to remove the resource, it calls
revocable_provider_revoke(). This function sets the internal resource
pointer to NULL and then calls synchronize_srcu() to wait for all
current readers to finish before the resource can be completely torn
down.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260116080235.350305-2-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, driver_match_device() is called from three sites. One site
(__device_attach_driver) holds device_lock(dev), but the other two
(bind_store and __driver_attach) do not. This inconsistency means that
bus match() callbacks are not guaranteed to be called with the lock
held.
Fix this by introducing driver_match_device_locked(), which guarantees
holding the device lock using a scoped guard. Replace the unlocked calls
in bind_store() and __driver_attach() with this new helper. Also add a
lock assertion to driver_match_device() to enforce this guarantee.
This consistency also fixes a known race condition. The driver_override
implementation relies on the device_lock, so the missing lock led to the
use-after-free (UAF) reported in Bugzilla for buses using this field.
Stress testing the two newly locked paths for 24 hours with
CONFIG_PROVE_LOCKING and CONFIG_LOCKDEP enabled showed no UAF recurrence
and no lockdep warnings.
Cc: stable@vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789
Suggested-by: Qiu-ji Chen <chenqiuji666@gmail.com>
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Fixes: 49b420a13f ("driver core: check bus->match without holding device lock")
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Link: https://patch.msgid.link/20260113162843.12712-1-hanguidong02@gmail.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Currently, the driver's device private data is allocated and initialized
from driver core code called from bus abstractions after the driver's
probe() callback returned the corresponding initializer.
Similarly, the driver's device private data is dropped within the
remove() callback of bus abstractions after calling the remove()
callback of the corresponding driver.
However, commit 6f61a2637a ("rust: device: introduce
Device::drvdata()") introduced an accessor for the driver's device
private data for a Device<Bound>, i.e. a device that is currently bound
to a driver.
Obviously, this is in conflict with dropping the driver's device private
data in remove(), since a device can not be considered to be fully
unbound after remove() has finished:
We also have to consider registrations guarded by devres - such as IRQ
or class device registrations - which are torn down after remove() in
devres_release_all().
Thus, it can happen that, for instance, a class device or IRQ callback
still calls Device::drvdata(), which then runs concurrently to remove()
(which sets dev->driver_data to NULL and drops the driver's device
private data), before devres_release_all() started to tear down the
corresponding registration. This is because devres guarded registrations
can, as expected, access the corresponding Device<Bound> that defines
their scope.
In C it simply is the driver's responsibility to ensure that its device
private data is freed after e.g. an IRQ registration is unregistered.
Typically, C drivers achieve this by allocating their device private data
with e.g. devm_kzalloc() before doing anything else, i.e. before e.g.
registering an IRQ with devm_request_threaded_irq(), relying on the
reverse order cleanup of devres.
Technically, we could do something similar in Rust. However, the
resulting code would be pretty messy:
In Rust we have to differentiate between allocated but uninitialized
memory and initialized memory in the type system. Thus, we would need to
somehow keep track of whether the driver's device private data object
has been initialized (i.e. probe() was successful and returned a valid
initializer for this memory) and conditionally call the destructor of
the corresponding object when it is freed.
This is because we'd need to allocate and register the memory of the
driver's device private data *before* it is initialized by the
initializer returned by the driver's probe() callback, because the
driver could already register devres guarded registrations within
probe() outside of the driver's device private data initializer.
Luckily there is a much simpler solution: Instead of dropping the
driver's device private data at the end of remove(), we just drop it
after the device has been fully unbound, i.e. after all devres callbacks
have been processed.
For this, we introduce a new post_unbind() callback private to the
driver-core, i.e. the callback is neither exposed to drivers, nor to bus
abstractions.
This way, the driver-core code can simply continue to conditionally
allocate the memory for the driver's device private data when the
driver's initializer is returned from probe() - no change needed - and
drop it when the driver-core code receives the post_unbind() callback.
Closes: https://lore.kernel.org/all/DEZMS6Y4A7XE.XE7EUBT5SJFJ@kernel.org/
Fixes: 6f61a2637a ("rust: device: introduce Device::drvdata()")
Acked-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Igor Korotin <igor.korotin.linux@gmail.com>
Link: https://patch.msgid.link/20260107103511.570525-7-dakr@kernel.org
[ Remove #ifdef CONFIG_RUST, rename post_unbind() to post_unbind_rust().
- Danilo]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Invisible symbol REGMAP defaults to y when any of the REGMAP_* symbols
is enabled, effectively auto-enabling it when needed. However,
REGMAP_SLIMBUS is missing from the list.
Currently this does not cause any issues, as all symbols selecting
REGMAP_SLIMBUS also select REGMAP and/or REGMAP_IRQ. Add REGMAP_SLIMBUS
to the list for consistency, and to prevent any future issues.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://patch.msgid.link/47872f8f4cf613e9710963bf871c6ac7b2ce81e8.1768494166.git.geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
Previously, the address of the shared member '&map->spinlock_flags' was
passed directly to 'hwspin_lock_timeout_irqsave'. This creates a race
condition where multiple contexts contending for the lock could overwrite
the shared flags variable, potentially corrupting the state for the
current lock owner.
Fix this by using a local stack variable 'flags' to store the IRQ state
temporarily.
Fixes: 8698b93647 ("regmap: Add hardware spinlock support")
Signed-off-by: Cheng-Yu Lee <cylee12@realtek.com>
Co-developed-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Link: https://patch.msgid.link/20260109032633.8732-1-eleanor.lin@realtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently, when a cpufreq policy is created, the AMU FIE setup process
checks all CPUs in the policy -- including those that are offline. If any
of these CPUs are offline at that time, their AMU capability flag hasn't
been verified yet, leading the check fail. As a result, AMU FIE is not
enabled, even if the CPUs that are online do support it.
Later, when the previously offline CPUs come online and report AMU support,
there's no mechanism in place to re-enable AMU FIE for the policy. This
leaves the entire frequency domain without AMU FIE, despite being eligible.
Restrict the initial AMU FIE check to only those CPUs that are online at
the time the policy is created, and allow CPUs that come online later to
join the policy with AMU FIE enabled.
Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Acked-by: Beata Michalska <beata.michalska@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
regcache_maple_write() allocates a new block ('entry') to merge
adjacent ranges and then stores it with mas_store_gfp().
When mas_store_gfp() fails, the new 'entry' remains allocated and
is never freed, leaking memory.
Free 'entry' on the failure path; on success continue freeing the
replaced neighbor blocks ('lower', 'upper').
Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Link: https://patch.msgid.link/20260105031820.260119-1-kaushlendra.kumar@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
