Pull workqueue updates from Tejun Heo:
- New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
smaller shards to improve scalability on machines with many CPUs per
LLC
- Misc:
- system_dfl_long_wq for long unbound works
- devm_alloc_workqueue() for device-managed allocation
- sysfs exposure for ordered workqueues and the EFI workqueue
- removal of HK_TYPE_WQ from wq_unbound_cpumask
- various small fixes
* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
workqueue: avoid unguarded 64-bit division
docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
workqueue: add test_workqueue benchmark module
tools/workqueue: add CACHE_SHARD support to wq_dump.py
workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
workqueue: fix typo in WQ_AFFN_SMT comment
workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
workqueue: unlink pwqs from wq->pwqs list in alloc_and_link_pwqs() error path
workqueue: Remove NULL wq WARN in __queue_delayed_work()
workqueue: fix parse_affn_scope() prefix matching bug
workqueue: devres: Add device-managed allocate workqueue
workqueue: Add system_dfl_long_wq for long unbound works
tools/workqueue/wq_dump.py: add NODE prefix to all node columns
tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
efi: Allow to expose the workqueue via sysfs
workqueue: Allow to expose ordered workqueues via sysfs
...
Add a Resource-managed version of alloc_workqueue() to fix common
problem of drivers mixing devm() calls with destroy_workqueue. Such
naive and discouraged driver approach leads to difficult to debug bugs
when the driver:
1. Allocates workqueue in standard way and destroys it in driver
remove() callback,
2. Sets work struct with devm_work_autocancel(),
3. Registers interrupt handler with devm_request_threaded_irq().
Which leads to following unbind/removal path:
1. destroy_workqueue() via driver remove(),
Any interrupt coming now would still execute the interrupt handler,
which queues work on destroyed workqueue.
2. devm_irq_release(),
3. devm_work_drop() -> cancel_work_sync() on destroyed workqueue.
devm_alloc_workqueue() has two benefits:
1. Solves above problem of mix-and-match devres and non-devres code in
driver,
2. Simplify any sane drivers which were correctly using
alloc_workqueue() + devm_add_action_or_reset().
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The root document usually has a special :ref:`genindex` link to the
generated index. This is also the case for Documentation/index.rst. The
other index.rst files deeper in the directory hierarchy usually don't.
For SPHINXDIRS builds, the root document isn't Documentation/index.rst,
but some other index.rst in the hierarchy. Currently they have a
".. only::" block to add the index link when doing SPHINXDIRS html
builds.
This is obviously very tedious and repetitive. The link is also added to
all index.rst files in the hierarchy for SPHINXDIRS builds, not just the
root document.
Put the boilerplate in a sphinx-includes/subproject-index.rst file, and
include it at the end of the root document for subproject builds in an
ad-hoc source-read extension defined in conf.py.
For now, keep having the boilerplate in translations, because this
approach currently doesn't cover translated index link headers.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[jc: did s/doctree/kern_doc_dir/ ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
The driver binding documentation (still) mentions that "When a driver is
attached to a device, the device is inserted into the driver's list of
devices.".
While it is true that the driver-core keeps track of all the devices
that are attached to a driver, this is purely for internal purposes
(i.e. it is an implementation detail) and has no relevance for user
facing documentation.
In fact, it is even misleading, since it could be read as if it were
valid for driver implementations to keep track of all the devices bound
to it.
Instead, drivers operate on a per-device basis, with a separate
per-device instance created when the driver is bound to a device.
Hence, remove the mention of a driver's list of devices and instead add
some documentation of the relationship between drivers and devices.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260115215718.6405-1-dakr@kernel.org>
For several years, and still ongoing, the kernel.h is being split
to smaller and narrow headers to avoid "including everything" approach
which is bad in many ways. Since that, documentation missed a few
required updates to align with that work. Do it here.
Note, language translations are left untouched and if anybody willing
to help, please provide path(es) based on the updated English variant.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251126214709.2322314-1-andriy.shevchenko@linux.intel.com>
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Make pci_stop_dev() and pci_destroy_dev() safe so concurrent
callers can't stop a device multiple times, even as we migrate from
the global pci_rescan_remove_lock to finer-grained locking (Keith
Busch)
- Improve pci_walk_bus() implementation by making it recursive and
moving locking up to avoid need for a 'locked' parameter (Keith
Busch)
- Unexport pci_walk_bus_locked(), which is only used internally by
the PCI core (Keith Busch)
- Detect some Thunderbolt chips that are built-in and hence
'trustworthy' by a heuristic since the 'ExternalFacingPort' and
'usb4-host-interface' ACPI properties are not quite enough (Esther
Shimanovich)
Resource management:
- Use PCI bus addresses (not CPU addresses) in 'ranges' properties
when building dynamic DT nodes so systems where PCI and CPU
addresses differ work correctly (Andrea della Porta)
- Tidy resource sizing and assignment with helpers to reduce
redundancy (Ilpo Järvinen)
- Improve pdev_sort_resources() 'bogus alignment' warning to be more
specific (Ilpo Järvinen)
Driver binding:
- Convert driver .remove_new() callbacks to .remove() again to finish
the conversion from returning 'int' to being 'void' (Sergio
Paracuellos)
- Export pcim_request_all_regions(), a managed interface to request
all BARs (Philipp Stanner)
- Replace pcim_iomap_regions_request_all() with
pcim_request_all_regions(), and pcim_iomap_table()[n] with
pcim_iomap(n), in the following drivers: ahci, crypto qat, crypto
octeontx2, intel_th, iwlwifi, ntb idt, serial rp2, ALSA korg1212
(Philipp Stanner)
- Remove the now unused pcim_iomap_regions_request_all() (Philipp
Stanner)
- Export pcim_iounmap_region(), a managed interface to unmap and
release a PCI BAR (Philipp Stanner)
- Replace pcim_iomap_regions(mask) with pcim_iomap_region(n), and
pcim_iounmap_regions(mask) with pcim_iounmap_region(n), in the
following drivers: fpga dfl-pci, block mtip32xx, gpio-merrifield,
cavium (Philipp Stanner)
Error handling:
- Add sysfs 'reset_subordinate' to reset the entire hierarchy below a
bridge; previously Secondary Bus Reset could only be used when
there was a single device below a bridge (Keith Busch)
- Warn if we reset a running device where the driver didn't register
pci_error_handlers notification callbacks (Keith Busch)
ASPM:
- Disable ASPM L1 before touching L1 PM Substates to follow the spec
closer and avoid a CPU load timeout on some platforms (Ajay
Agarwal)
- Set devices below Intel VMD to D0 before enabling ASPM L1 Substates
as required per spec for all L1 Substates changes (Jian-Hong Pan)
Power management:
- Enable starfive controller runtime PM before probing host bridge
(Mayank Rana)
- Enable runtime power management for host bridges (Krishna chaitanya
chundru)
Power control:
- Use of_platform_device_create() instead of of_platform_populate()
to create pwrctl platform devices so we can control it based on the
child nodes (Manivannan Sadhasivam)
- Create pwrctrl platform devices only if there's a relevant power
supply property (Manivannan Sadhasivam)
- Add device link from the pwrctl supplier to the PCI dev to ensure
pwrctl drivers are probed before the PCI dev driver; this avoids a
race where pwrctl could change device power state while the PCI
driver was active (Manivannan Sadhasivam)
- Find pwrctl device for removal with of_find_device_by_node()
instead of searching all children of the parent (Manivannan
Sadhasivam)
- Rename 'pwrctl' to 'pwrctrl' to match new bandwidth controller
('bwctrl') and hotplug files (Bjorn Helgaas)
Bandwidth control:
- Add read/modify/write locking for Link Control 2, which is used to
manage Link speed (Ilpo Järvinen)
- Extract Link Bandwidth Management Status check into
pcie_lbms_seen(), where it can be shared between the bandwidth
controller and quirks that use it to help retrain failed links
(Ilpo Järvinen)
- Re-add Link Bandwidth notification support with updates to address
the reasons it was previously reverted (Alexandru Gagniuc, Ilpo
Järvinen)
- Add pcie_set_target_speed() and related functionality so drivers
can manage PCIe Link speed based on thermal or other constraints
(Ilpo Järvinen)
- Add a thermal cooling driver to throttle PCIe Links via the
existing thermal management framework (Ilpo Järvinen)
- Add a userspace selftest for the PCIe bandwidth controller (Ilpo
Järvinen)
PCI device hotplug:
- Add hotplug controller driver for Marvell OCTEON multi-function
device where function 0 has a management console interface to
enable/disable and provision various personalities for the other
functions (Shijith Thotton)
- Retain a reference to the pci_bus for the lifetime of a pci_slot to
avoid a use-after-free when the thunderbolt driver resets USB4 host
routers on boot, causing hotplug remove/add of downstream docks or
other devices (Lukas Wunner)
- Remove unused cpcihp struct cpci_hp_controller_ops.hardware_test
(Guilherme Giacomo Simoes)
- Remove unused cpqphp struct ctrl_dbg.ctrl (Christophe JAILLET)
- Use pci_bus_read_dev_vendor_id() instead of hand-coded presence
detection in cpqphp (Ilpo Järvinen)
- Simplify cpqphp enumeration, which is already simple-minded and
doesn't handle devices below hot-added bridges (Ilpo Järvinen)
Virtualization:
- Add ACS quirk for Wangxun FF5xxx NICs, which don't advertise an ACS
capability but do isolate functions as though PCI_ACS_RR and
PCI_ACS_CR were set, so the functions can be in independent IOMMU
groups (Mengyuan Lou)
TLP Processing Hints (TPH):
- Add and document TLP Processing Hints (TPH) support so drivers can
enable and disable TPH and the kernel can save/restore TPH
configuration (Wei Huang)
- Add TPH Steering Tag support so drivers can retrieve Steering Tag
values associated with specific CPUs via an ACPI _DSM to improve
performance by directing DMA writes closer to their consumers (Wei
Huang)
Data Object Exchange (DOE):
- Wait up to 1 second for DOE Busy bit to clear before writing a
request to the mailbox to avoid failures if the mailbox is still
busy from a previous transfer (Gregory Price)
Endpoint framework:
- Skip attempts to allocate from endpoint controller memory window if
the requested size is larger than the window (Damien Le Moal)
- Add and document pci_epc_mem_map() and pci_epc_mem_unmap() to
handle controller-specific size and alignment constraints, and add
test cases to the endpoint test driver (Damien Le Moal)
- Implement dwc pci_epc_ops.align_addr() so pci_epc_mem_map() can
observe DWC-specific alignment requirements (Damien Le Moal)
- Synchronously cancel command handler work in endpoint test before
cleaning up DMA and BARs (Damien Le Moal)
- Respect endpoint page size in dw_pcie_ep_align_addr() (Niklas
Cassel)
- Use dw_pcie_ep_align_addr() in dw_pcie_ep_raise_msi_irq() and
dw_pcie_ep_raise_msix_irq() instead of open coding the equivalent
(Niklas Cassel)
- Avoid NULL dereference if Modem Host Interface Endpoint lacks
'mmio' DT property (Zhongqiu Han)
- Release PCI domain ID of Endpoint controller parent (not controller
itself) and before unregistering the controller, to avoid
use-after-free (Zijun Hu)
- Clear secondary (not primary) EPC in pci_epc_remove_epf() when
removing the secondary controller associated with an NTB (Zijun Hu)
Cadence PCIe controller driver:
- Lower severity of 'phy-names' message (Bartosz Wawrzyniak)
Freescale i.MX6 PCIe controller driver:
- Fix suspend/resume support on i.MX6QDL, which has a hardware
erratum that prevents use of L2 (Stefan Eichenberger)
Intel VMD host bridge driver:
- Add 0xb60b and 0xb06f Device IDs for client SKUs (Nirmal Patel)
MediaTek PCIe Gen3 controller driver:
- Update mediatek-gen3 DT binding to require the exact number of
clocks for each SoC (Fei Shao)
- Add support for DT 'max-link-speed' and 'num-lanes' properties to
restrict the link speed and width (AngeloGioacchino Del Regno)
Microchip PolarFlare PCIe controller driver:
- Add DT and driver support for using either of the two PolarFire
Root Ports (Conor Dooley)
NVIDIA Tegra194 PCIe controller driver:
- Move endpoint controller cleanups that depend on refclk from the
host to the notifier that tells us the host has deasserted PERST#,
when refclk should be valid (Manivannan Sadhasivam)
Qualcomm PCIe controller driver:
- Add qcom SAR2130P DT binding with an additional clock (Dmitry
Baryshkov)
- Enable MSI interrupts if 'global' IRQ is supported, since a
previous commit unintentionally masked them (Manivannan Sadhasivam)
- Move endpoint controller cleanups that depend on refclk from the
host to the notifier that tells us the host has deasserted PERST#,
when refclk should be valid (Manivannan Sadhasivam)
- Add DT binding and driver support for IPQ9574, with Synopsys IP
v5.80a and Qcom IP 1.27.0 (devi priya)
- Move the OPP "operating-points-v2" table from the
qcom,pcie-sm8450.yaml DT binding to qcom,pcie-common.yaml, where it
can be used by other Qcom platforms (Qiang Yu)
- Add 'global' SPI interrupt for events like link-up, link-down to
qcom,pcie-x1e80100 DT binding so we can start enumeration when the
link comes up (Qiang Yu)
- Disable ASPM L0s for qcom,pcie-x1e80100 since the PHY is not tuned
to support this (Qiang Yu)
- Add ops_1_21_0 for SC8280X family SoC, which doesn't use the
'iommu-map' DT property and doesn't need BDF-to-SID translation
(Qiang Yu)
Rockchip PCIe controller driver:
- Define ROCKCHIP_PCIE_AT_SIZE_ALIGN to replace magic 256 endpoint
.align value (Damien Le Moal)
- When unmapping an endpoint window, compute the region index instead
of searching for it, and verify that the address was mapped (Damien
Le Moal)
- When mapping an endpoint window, verify that the address hasn't
been mapped already (Damien Le Moal)
- Implement pci_epc_ops.align_addr() for rockchip-ep (Damien Le Moal)
- Fix MSI IRQ data mapping to observe the alignment constraint, which
fixes intermittent page faults in memcpy_toio() and memcpy_fromio()
(Damien Le Moal)
- Rename rockchip_pcie_parse_ep_dt() to
rockchip_pcie_ep_get_resources() for consistency with similar DT
interfaces (Damien Le Moal)
- Skip the unnecessary link train in rockchip_pcie_ep_probe() and do
it only in the endpoint start operation (Damien Le Moal)
- Implement pci_epc_ops.stop_link() to disable link training and
controller configuration (Damien Le Moal)
- Attempt link training at 5 GT/s when both partners support it
(Damien Le Moal)
- Add a handler for PERST# signal so we can detect host-initiated
resets and start link training after PERST# is deasserted (Damien
Le Moal)
Synopsys DesignWare PCIe controller driver:
- Clear outbound address on unmap so dw_pcie_find_index() won't match
an ATU index that was already unmapped (Damien Le Moal)
- Use of_property_present() instead of of_property_read_bool() when
testing for presence of non-boolean DT properties (Rob Herring)
- Advertise 1MB size if endpoint supports Resizable BARs, which was
inadvertently lost in v6.11 (Niklas Cassel)
TI J721E PCIe driver:
- Add PCIe support for J722S SoC (Siddharth Vadapalli)
- Delay PCIE_T_PVPERL_MS (100 ms), not just PCIE_T_PERST_CLK_US (100
us), before deasserting PERST# to ensure power and refclk are
stable (Siddharth Vadapalli)
TI Keystone PCIe controller driver:
- Set the 'ti,keystone-pcie' mode so v3.65a devices work in Root
Complex mode (Kishon Vijay Abraham I)
- Try to avoid unrecoverable SError for attempts to issue config
transactions when the link is down; this is racy but the best we
can do (Kishon Vijay Abraham I)
Miscellaneous:
- Reorganize kerneldoc parameter names to match order in function
signature (Julia Lawall)
- Fix sysfs reset_method_store() memory leak (Todd Kjos)
- Simplify pci_create_slot() (Ilpo Järvinen)
- Fix incorrect printf format specifiers in pcitest (Luo Yifan)"
* tag 'pci-v6.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (127 commits)
PCI: rockchip-ep: Handle PERST# signal in EP mode
PCI: rockchip-ep: Improve link training
PCI: rockship-ep: Implement the pci_epc_ops::stop_link() operation
PCI: rockchip-ep: Refactor endpoint link training enable
PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() MSI-X hiding
PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() memory allocations
PCI: rockchip-ep: Rename rockchip_pcie_parse_ep_dt()
PCI: rockchip-ep: Fix MSI IRQ data mapping
PCI: rockchip-ep: Implement the pci_epc_ops::align_addr() operation
PCI: rockchip-ep: Improve rockchip_pcie_ep_map_addr()
PCI: rockchip-ep: Improve rockchip_pcie_ep_unmap_addr()
PCI: rockchip-ep: Use a macro to define EP controller .align feature
PCI: rockchip-ep: Fix address translation unit programming
PCI/pwrctrl: Rename pwrctrl functions and structures
PCI/pwrctrl: Rename pwrctl files to pwrctrl
PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent
PCI/pwrctl: Ensure that pwrctl drivers are probed before PCI client drivers
PCI/pwrctl: Create pwrctl device only if at least one power supply is present
PCI/pwrctl: Use of_platform_device_create() to create pwrctl devices
tools: PCI: Fix incorrect printf format specifiers
...
The documentation states that pcim_enable_device() will make "all PCI
ops" managed. This is totally false, only a small subset of PCI
functions become managed that way. Implicating otherwise has caused at
least one bug so far, namely in commit 8558de401b ("drm/vboxvideo: use
managed pci functions").
Change the function summary so the functions dangerous behavior becomes
obvious.
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240809095248.14220-2-pstanner@redhat.com
Pull documentation updates from Jonathan Corbet:
"Nothing hugely exciting happening in the documentation tree this time
around, mostly more of the usual:
- More Spanish, Italian, and Chinese translations
- A new script, scripts/checktransupdate.py, can be used to see which
commits have touched an (English) document since a given
translation was last updated.
- A couple of "best practices" suggestions (on Link: tags and
off-list discussions) that were not entirely at consensus level,
but I concluded they were close enough to accept.
- Some nice cleanups removing documentation for kernel parameters
that have not been recognized for ... a long time.
...along with the usual updates, typo fixes, and such"
* tag 'docs-6.11' of git://git.lwn.net/linux: (57 commits)
Documentation: Document user_events ioctl code
docs/pinctrl: fix typo in mapping example
docs: maintainer: discourage taking conversations off-list
docs: driver-model: platform: update the definition of platform_driver
docs/sp_SP: Add translation for scheduler/sched-design-CFS.rst
writing_musb_glue_layer.rst: Fix broken URL
zh_CN/admin-guide: one typo fix
docs/zh_CN/virt: Update the translation of guest-halt-polling.rst
Documentation: add reference from dynamic debug to loglevel kernel params
Documentation: best practices for using Link trailers
Documentation: fix links to mailing list services
Documentation: exception-tables.rst: Fix the wrong steps referenced
docs/zh_CN: add process/researcher-guidelines Chinese translation
Documentation/tools/rv: fix document header
docs/sp_SP: Add translation of process/maintainer-kvm-x86.rst
docs/admin-guide/mm: correct typo 'quired' to 'queried'
Add libps2 to the input section of driver-api
Docs/mm/index: move allocation profiling document to unsorted documents chapter
Docs/mm/index: rename 'Legacy Documentation' to 'Unsorted Documentation'
Docs/mm/index: Remove 'Memory Management Guide' chapter marker
...