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2026-01-31kernel.h: move VERIFY_OCTAL_PERMISSIONS() to sysfs.hYury Norov
The macro is related to sysfs, but is defined in kernel.h. Move it to the proper header, and unload the generic kernel.h. Now that the macro is removed from kernel.h, linux/moduleparam.h is decoupled, and kernel.h inclusion can be removed. Link: https://lkml.kernel.org/r/20260116042510.241009-4-ynorov@nvidia.com Signed-off-by: Yury Norov <ynorov@nvidia.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Pavlu <petr.pavlu@suse.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com> Cc: Aaron Tomlin <atomlin@atomlin.com> Cc: Andi Shyti <andi.shyti@linux.intel.com> Cc: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-03Merge tag 'docs-6.18' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle in docsland, with changes all over: - Bring the kernel memory-model docs into the Sphinx build in the "literal include" mode. - Lots of build-infrastructure work, further cleaning up long-term kernel-doc technical debt. The sphinx-pre-install tool has been converted to Python and updated for current systems. - A new tool to detect when documents have been moved and generate HTML redirects; this can be used on kernel.org (or any other site hosting the rendered docs) to avoid breaking links. - Automated processing of the YAML files describing the netlink protocol. - A significant update of the maintainer's PGP guide. ... and a seemingly endless series of typo fixes, build-problem fixes, etc" * tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits) Documentation/features: Update feature lists for 6.17-rc7 docs: remove cdomain.py Documentation/process: submitting-patches: fix typo in "were do" docs: dev-tools/lkmm: Fix typo of missing file extension Documentation: trace: histogram: Convert ftrace docs cross-reference Documentation: trace: histogram-design: Wrap introductory note in note:: directive Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text Documentation: trace: histogram: Fix histogram trigger subsection number order docs: driver-api: fix spelling of "buses". Documentation: fbcon: Use admonition directives Documentation: fbcon: Reindent 8th step of attach/detach/unload Documentation: fbcon: Add boot options and attach/detach/unload section headings docs: filesystems: sysfs: add remaining top level sysfs directory descriptions docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions docs: filesystems: sysfs: remove top level sysfs net directory docs: maintainer: Fix ambiguous subheading formatting docs: kdoc: a few more dump_typedef() tweaks docs: kdoc: remove redundant comment stripping in dump_typedef() docs: kdoc: remove some dead code in dump_typedef() ...
2025-09-18docs: filesystems: sysfs: add remaining top level sysfs directory descriptionsAlex Tran
Finish top level sysfs directory descriptions for block, class, firmware, hypervisor, kernel, and power. Did not write one for net directory. See commit bc3a88431672 ("docs: filesystems: sysfs: remove top level sysfs net directory") Signed-off-by: Alex Tran <alex.t.tran@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250902023039.1351270-1-alex.t.tran@gmail.com>
2025-09-18docs: filesystems: sysfs: clarify symlink destinations in dev and ↵Alex Tran
bus/devices descriptions Change sysfs bus/devices and dev directory descriptions to provide more verbose information about the specific symlink destination the devices point to. Signed-off-by: Alex Tran <alex.t.tran@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250902023039.1351270-2-alex.t.tran@gmail.com>
2025-09-18docs: filesystems: sysfs: remove top level sysfs net directoryAlex Tran
The net/ directory is not present as a top level sysfs directory in standard Linux systems. Network interfaces can be accessible via /sys/class/net instead. Signed-off-by: Alex Tran <alex.t.tran@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250902023039.1351270-3-alex.t.tran@gmail.com>
2025-09-02fuse: fix references to fuse.rst -> fuse/fuse.rstMiklos Szeredi
Commit 6be0ddb20200 ("Documentation: fuse: Consolidate FUSE docs into its own subdirectory") moved fuse docs to a subdirectory but didn't update references inside the kernel tree. Fixes: 6be0ddb20200 ("Documentation: fuse: Consolidate FUSE docs into its own subdirectory") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202508261621.EaNMWVjm-lkp@intel.com/ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-08-11docs: filesystems: sysfs: Recommend sysfs_emit() for new code onlyBart Van Assche
The advantages of converting existing sysfs show() methods to sysfs_emit() and sysfs_emit_at() do not outweigh the risk of introducing bugs. Hence recommend sysfs_emit() and sysfs_emit_at() only for new implementations of show() methods. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250724153449.2433395-1-bvanassche@acm.org
2023-03-23driver core: bus: mark the struct bus_type for sysfs callbacks as constantGreg Kroah-Hartman
struct bus_type should never be modified in a sysfs callback as there is nothing in the structure to modify, and frankly, the structure is almost never used in a sysfs callback, so mark it as constant to allow struct bus_type to be moved to read-only memory. Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Bounine <alex.bou9@gmail.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ben Widawsky <bwidawsk@kernel.org> Cc: Dexuan Cui <decui@microsoft.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Harald Freudenberger <freude@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hu Haowen <src.res@email.cn> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Stuart Yoder <stuyoder@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Yanteng Si <siyanteng@loongson.cn> Acked-by: Ilya Dryomov <idryomov@gmail.com> # rbd Acked-by: Ira Weiny <ira.weiny@intel.com> # cxl Reviewed-by: Alex Shi <alexs@kernel.org> Acked-by: Iwona Winiarska <iwona.winiarska@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi Link: https://lore.kernel.org/r/20230313182918.1312597-23-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-09sysfs: update DocumentationRandy Dunlap
Make editing corrections and updates to sysfs.rst: - spell "sysfs" consistently (vs. "Sysfs") - align field names in a struct - fix some punctuation and grammar - list more /sys top-level subdirectories - change 'fuse.txt' to 'fuse.rst' (although I don't see where the example is) Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: "Rafael J. Wysocki" <rafael@kernel.org> Link: https://lore.kernel.org/r/20221104003921.31616-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-30docs: filesystems: sysfs: Make text and code for ->show() consistentAndy Shevchenko
The documentation says that ->show() should only use sysfs_emit() or sysfs_emit_at(), but example keeps outdated code. Update the code to be consistent. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220928135741.54919-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-14Merge tag 'driver-core-5.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 5.10-rc1 They include a lot of different things, all related to the driver core and/or some driver logic: - sysfs common write functions to make it easier to audit sysfs attributes - device connection cleanups and fixes - devm helpers for a few functions - NOIO allocations for when devices are being removed - minor cleanups and fixes All have been in linux-next for a while with no reported issues" * tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits) regmap: debugfs: use semicolons rather than commas to separate statements platform/x86: intel_pmc_core: do not create a static struct device drivers core: node: Use a more typical macro definition style for ACCESS_ATTR drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit drivers core: Miscellaneous changes for sysfs_emit drivers core: Reindent a couple uses around sysfs_emit drivers core: Remove strcat uses around sysfs_emit and neaten drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output dyndbg: use keyword, arg varnames for query term pairs driver core: force NOIO allocations during unplug platform_device: switch to simpler IDA interface driver core: platform: Document return type of more functions Revert "driver core: Annotate dev_err_probe() with __must_check" Revert "test_firmware: Test platform fw loading on non-EFI systems" iio: adc: xilinx-xadc: use devm_krealloc() hwmon: pmbus: use more devres helpers devres: provide devm_krealloc() syscore: Use pm_pr_dbg() for syscore_{suspend,resume}() ...
2020-10-02sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs outputJoe Perches
Output defects can exist in sysfs content using sprintf and snprintf. sprintf does not know the PAGE_SIZE maximum of the temporary buffer used for outputting sysfs content and it's possible to overrun the PAGE_SIZE buffer length. Add a generic sysfs_emit function that knows that the size of the temporary buffer and ensures that no overrun is done. Add a generic sysfs_emit_at function that can be used in multiple call situations that also ensures that no overrun is done. Validate the output buffer argument to be page aligned. Validate the offset len argument to be within the PAGE_SIZE buf. Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-09docs: filesystems: replace to_dev() with kobj_to_dev()Denis Efremov
Commit a4232963757e ("driver-core: Move kobj_to_dev from genhd.h to device.h") introduced kobj_to_dev() function. Signed-off-by: Denis Efremov <efremov@linux.com> Link: https://lore.kernel.org/r/20200830144135.6956-1-efremov@linux.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20docs: filesystems: fix renamed referencesMauro Carvalho Chehab
Some filesystem references got broken by a previous patch series I submitted. Address those. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02docs: filesystems: convert sysfs.txt to ReSTMauro Carvalho Chehab
- Add a SPDX header; - Add a document title; - Adjust document and section titles; - use :field: markup; - Some whitespace fixes and new line breaks; - Mark literal blocks as such; - Add it to filesystems/index.rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/5c480dcb467315b5df6e25372a65e473b585c36d.1581955849.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>