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2024-01-11Merge tag 'docs-6.8' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation update from Jonathan Corbet: "Another moderately busy cycle for documentation, including: - The minimum Sphinx requirement has been raised to 2.4.4, following a warning that was added in 6.2 - Some reworking of the Documentation/process front page to, hopefully, make it more useful - Various kernel-doc tweaks to, for example, make it deal properly with __counted_by annotations - We have also restored a warning for documentation of nonexistent structure members that disappeared a while back. That had the delightful consequence of adding some 600 warnings to the docs build. A sustained effort by Randy, Vegard, and myself has addressed almost all of those, bringing the documentation back into sync with the code. The fixes are going through the appropriate maintainer trees - Various improvements to the HTML rendered docs, including automatic links to Git revisions and a nice new pulldown to make translations easy to access - Speaking of translations, more of those for Spanish and Chinese ... plus the usual stream of documentation updates and typo fixes" * tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits) MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL A reworked process/index.rst ring-buffer/Documentation: Add documentation on buffer_percent file Translated the RISC-V architecture boot documentation. Docs: remove mentions of fdformat from util-linux Docs/zh_CN: Fix the meaning of DEBUG to pr_debug() Documentation: move driver-api/dcdbas to userspace-api/ Documentation: move driver-api/isapnp to userspace-api/ Documentation/core-api : fix typo in workqueue Documentation/trace: Fixed typos in the ftrace FLAGS section kernel-doc: handle a void function without producing a warning scripts/get_abi.pl: ignore some temp files docs: kernel_abi.py: fix command injection scripts/get_abi: fix source path leak CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer docs: translations: add translations links when they exist kernel-doc: Align quick help and the code MAINTAINERS: add reviewer for Spanish translations docs: ignore __counted_by attribute in structure definitions scripts: kernel-doc: Clarify missing struct member description ..
2024-01-03kernel-doc: handle a void function without producing a warningRandy Dunlap
Currently a void function can produce a warning: main.c:469: warning: contents before sections This one is from arch/x86/kernel/cpu/sgx/main.c (which is not included in any produced kernel documentation output). Handle this by setting $in_doc_sect to 1 whenever any recognized document section name is processed. Fixes: f624adef3d0b ("kernel-doc: limit the "section header:" detection to a select few") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231226065219.319-1-rdunlap@infradead.org
2023-12-19kernel-doc: Align quick help and the codeAndy Shevchenko
The update to the quick help mentions -Wshort-description, but code never supported for that. Align that with the code by allowing both: -Wshort-description and -Wshort-desc. Fixes: 56b0f453db74 ("kernel-doc: don't let V=1 change outcome") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231215150341.1996720-1-andriy.shevchenko@linux.intel.com
2023-12-18docs: ignore __counted_by attribute in structure definitionsJonathan Corbet
kernel-doc appeared to ignore __counted_by, but appearances can be deceiving; it caused member names to not be recognized, which manifested as a number of spurious "Excess struct member" warnings. Filter that attribute out and reduce the warning onslaught slightly. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-12-15scripts: kernel-doc: Clarify missing struct member descriptionKees Cook
The output "or member" should be more specific, instead saying "struct member". Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231215001513.work.563-kees@kernel.org
2023-12-15scripts/kernel-doc: restore warning for Excess struct/unionRandy Dunlap
The warning for Excess struct or union member description was removed when the $nested parameter of check_sections() was removed. This causes some kernel-doc notation warnings to be missed. Recently the kernel test robot somehow reported an Excess member. The code in kernel-doc has not issued that warning since kernel v4.16, so I don't know how the robot did it. (See the Link for the report.) drivers/net/wireless/intel/iwlwifi/fw/dbg.c:86: warning: Excess struct/union/enum/typedef member 'trans_len' description in 'iwl_fw_dump_ptrs' I patched that warning away even though I could not reproduce the warning from kernel-doc. The warning should be issued for extraneous struct member or union member description, so restore it. Fixes: 1081de2d2f91 ("scripts: kernel-doc: get rid of $nested parameter") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/all/202312060810.QT9zourt-lkp@intel.com/ Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231214070200.24405-1-rdunlap@infradead.org
2023-12-02cache: enforce cache groupsCoco Li
Set up build time warnings to safeguard against future header changes of organized structs. Warning includes: 1) whether all variables are still in the same cache group 2) whether all the cache groups have the sum of the members size (in the maximum condition, including all members defined in configs) The __cache_group* variables are ignored in kernel-doc check in the various header files they appear in to enforce the cache groups. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Coco Li <lixiaoyan@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-30scripts/kernel-doc: Fix the regex for matching -Werror flagYujie Liu
Swarup reported a "make htmldocs" warning: Variable length lookbehind is experimental in regex; marked by <-- HERE in m/(?<=^|\s)-Werror(?=$|\s) <-- HERE / at ./scripts/kernel-doc line 188. Akira managed to reproduce it by perl v5.34.0. On second thought, it is not necessary to have the complicated "lookahead and lookbehind" things, and the regex can be simplified. Generally, the kernel-doc warnings should be considered as errors only when "-Werror" flag is set in KCFLAGS, but not when "-Werror=<diagnostic-type>" is set, which means there needs to be a space or start of string before "-Werror", and a space or end of string after "-Werror". The following cases have been tested to work as expected: * kernel-doc warnings are considered as errors: $ KCFLAGS="-Werror" make W=1 $ KCFLAGS="-Wcomment -Werror" make W=1 $ KCFLAGS="-Werror -Wundef" make W=1 $ KCFLAGS="-Wcomment -Werror -Wundef" make W=1 * kernel-doc warnings remain as warnings: $ KCFLAGS="-Werror=return-type" make W=1 $ KCFLAGS="-Wcomment -Werror=return-type" make W=1 $ KCFLAGS="-Werror=return-type -Wundef" make W=1 $ KCFLAGS="-Wcomment -Werror=return-type -Wundef" make W=1 The "Variable length lookbehind is experimental in regex" warning is also resolved by this patch. Fixes: 91f950e8b9d8 ("scripts/kernel-doc: match -Werror flag strictly") Reported-by: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com> Signed-off-by: Yujie Liu <yujie.liu@intel.com> Closes: https://lore.kernel.org/r/20231028182231.123996-1-swarupkotikalapudi@gmail.com/ Reviewed-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231030085404.3343403-1-yujie.liu@intel.com
2023-10-22scripts/kernel-doc: match -Werror flag strictlyYujie Liu
In our CI testing, we use some commands as below to only turn a specific type of warnings into errors, but we notice that kernel-doc warnings are also turned into errors unexpectedly. $ make KCFLAGS="-Werror=return-type" W=1 kernel/fork.o kernel/fork.c:1406: warning: Function parameter or member 'mm' not described in 'set_mm_exe_file' kernel/fork.c:1406: warning: Function parameter or member 'new_exe_file' not described in 'set_mm_exe_file' kernel/fork.c:1441: warning: Function parameter or member 'mm' not described in 'replace_mm_exe_file' kernel/fork.c:1441: warning: Function parameter or member 'new_exe_file' not described in 'replace_mm_exe_file' kernel/fork.c:1491: warning: Function parameter or member 'mm' not described in 'get_mm_exe_file' kernel/fork.c:1510: warning: Function parameter or member 'task' not described in 'get_task_exe_file' kernel/fork.c:1534: warning: Function parameter or member 'task' not described in 'get_task_mm' kernel/fork.c:2109: warning: bad line: kernel/fork.c:2130: warning: Function parameter or member 'ret' not described in '__pidfd_prepare' kernel/fork.c:2130: warning: Excess function parameter 'pidfd' description in '__pidfd_prepare' kernel/fork.c:2179: warning: Function parameter or member 'ret' not described in 'pidfd_prepare' kernel/fork.c:2179: warning: Excess function parameter 'pidfd' description in 'pidfd_prepare' kernel/fork.c:3195: warning: expecting prototype for clone3(). Prototype was for sys_clone3() instead 13 warnings as Errors make[3]: *** [scripts/Makefile.build:243: kernel/fork.o] Error 13 make[3]: *** Deleting file 'kernel/fork.o' make[2]: *** [scripts/Makefile.build:480: kernel] Error 2 make[1]: *** [/root/linux/Makefile:1913: .] Error 2 make: *** [Makefile:234: __sub-make] Error 2 >From the git history, commit 2c12c8103d8f ("scripts/kernel-doc: optionally treat warnings as errors") introduces a new command-line option to make kernel-doc warnings into errors. It can also read the KCFLAGS environment variable to decide whether to turn this option on, but the regex used for matching may not be accurate enough. It can match both "-Werror" and "-Werror=<diagnostic-type>", so the option is turned on by mistake in the latter case. Fix this by strictly matching the flag "-Werror": there must be a space or start of string in the front, and a space or end of string at the end. This can handle all the following cases correctly: KCFLAGS="-Werror" make W=1 [MATCH] KCFLAGS="-Werror=return-type" make W=1 [NO MATCH] KCFLAGS="-Wcomment -Werror -Wundef" make W=1 [MATCH] KCFLAGS="-Wcomment -Werror=return-type -Wundef" make W=1 [NO MATCH] Fixes: 2c12c8103d8f ("scripts/kernel-doc: optionally treat warnings as errors") Signed-off-by: Yujie Liu <yujie.liu@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20231019095637.2471840-1-yujie.liu@intel.com>
2023-08-18scripts: kernel-doc: fix macro handling in enumsPavan Kumar Linga
drivers/net/ethernet/intel/idpf/idpf.h uses offsetof to initialize the enum enumerators: enum idpf_cap_field { IDPF_BASE_CAPS = -1, IDPF_CSUM_CAPS = offsetof(struct virtchnl2_get_capabilities, csum_caps), IDPF_SEG_CAPS = offsetof(struct virtchnl2_get_capabilities, seg_caps), IDPF_RSS_CAPS = offsetof(struct virtchnl2_get_capabilities, rss_caps), IDPF_HSPLIT_CAPS = offsetof(struct virtchnl2_get_capabilities, hsplit_caps), IDPF_RSC_CAPS = offsetof(struct virtchnl2_get_capabilities, rsc_caps), IDPF_OTHER_CAPS = offsetof(struct virtchnl2_get_capabilities, other_caps), }; kernel-doc parses the above enumerator with a ',' inside the macro and treats 'csum_caps', 'seg_caps' etc. also as enumerators resulting in the warnings: drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'csum_caps' not described in enum 'idpf_cap_field' drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'seg_caps' not described in enum 'idpf_cap_field' drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'rss_caps' not described in enum 'idpf_cap_field' drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'hsplit_caps' not described in enum 'idpf_cap_field' drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'rsc_caps' not described in enum 'idpf_cap_field' drivers/net/ethernet/intel/idpf/idpf.h:130: warning: Enum value 'other_caps' not described in enum 'idpf_cap_field' Fix it by removing the macro arguments within the parentheses. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230815210417.98749-3-pavan.kumar.linga@intel.com
2023-08-18scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN]Pavan Kumar Linga
At present, if the macros DEFINE_DMA_UNMAP_ADDR() and DEFINE_DMA_UNMAP_LEN() are used in the structures as shown below, instead of parsing the parameter in the parentheses, kernel-doc parses 'DEFINE_DMA_UNMAP_ADDR(' and 'DEFINE_DMA_UNMAP_LEN(' which results in the following warnings: drivers/net/ethernet/intel/idpf/idpf_txrx.h:201: warning: Function parameter or member 'DEFINE_DMA_UNMAP_ADDR(dma' not described in 'idpf_tx_buf' drivers/net/ethernet/intel/idpf/idpf_txrx.h:201: warning: Function parameter or member 'DEFINE_DMA_UNMAP_LEN(len' not described in 'idpf_tx_buf' struct idpf_tx_buf { DEFINE_DMA_UNMAP_ADDR(dma); DEFINE_DMA_UNMAP_LEN(len); }; Fix the warnings by parsing DEFINE_DMA_UNMAP_ADDR() and DEFINE_DMA_UNMAP_LEN(). Cc: Jonathan Corbet <corbet@lwn.net> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230815210417.98749-2-pavan.kumar.linga@intel.com
2023-07-06Merge tag 'docs-6.5-2' of git://git.lwn.net/linuxLinus Torvalds
Pull mode documentation updates from Jonathan Corbet: "A half-dozen late arriving docs patches. They are mostly fixes, but we also have a kernel-doc tweak for enums and the long-overdue removal of the outdated and redundant patch-submission comments at the top of the MAINTAINERS file" * tag 'docs-6.5-2' of git://git.lwn.net/linux: scripts: kernel-doc: support private / public marking for enums Documentation: KVM: SEV: add a missing backtick Documentation: ACPI: fix typo in ssdt-overlays.rst Fix documentation of panic_on_warn docs: remove the tips on how to submit patches from MAINTAINERS docs: fix typo in zh_TW and zh_CN translation
2023-07-04scripts: kernel-doc: support private / public marking for enumsJakub Kicinski
Enums benefit from private markings, too. For netlink attribute name enums always end with a pair of __$n_MAX and $n_MAX members. Documenting them feels a bit tedious. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20230621223525.2722703-1-kuba@kernel.org>
2023-07-01Merge tag 'kbuild-v6.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Remove the deprecated rule to build *.dtbo from *.dts - Refactor section mismatch detection in modpost - Fix bogus ARM section mismatch detections - Fix error of 'make gtags' with O= option - Add Clang's target triple to KBUILD_CPPFLAGS to fix a build error with the latest LLVM version - Rebuild the built-in initrd when KBUILD_BUILD_TIMESTAMP is changed - Ignore more compiler-generated symbols for kallsyms - Fix 'make local*config' to handle the ${CONFIG_FOO} form in Makefiles - Enable more kernel-doc warnings with W=2 - Refactor <linux/export.h> by generating KSYMTAB data by modpost - Deprecate <asm/export.h> and <asm-generic/export.h> - Remove the EXPORT_DATA_SYMBOL macro - Move the check for static EXPORT_SYMBOL back to modpost, which makes the build faster - Re-implement CONFIG_TRIM_UNUSED_KSYMS with one-pass algorithm - Warn missing MODULE_DESCRIPTION when building modules with W=1 - Make 'make clean' robust against too long argument error - Exclude more objects from GCOV to fix CFI failures with GCOV - Allow 'make modules_install' to install modules.builtin and modules.builtin.modinfo even when CONFIG_MODULES is disabled - Include modules.builtin and modules.builtin.modinfo in the linux-image Debian package even when CONFIG_MODULES is disabled - Revive "Entering directory" logging for the latest Make version * tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (72 commits) modpost: define more R_ARM_* for old distributions kbuild: revive "Entering directory" for Make >= 4.4.1 kbuild: set correct abs_srctree and abs_objtree for package builds scripts/mksysmap: Ignore prefixed KCFI symbols kbuild: deb-pkg: remove the CONFIG_MODULES check in buildeb kbuild: builddeb: always make modules_install, to install modules.builtin* modpost: continue even with unknown relocation type modpost: factor out Elf_Sym pointer calculation to section_rel() modpost: factor out inst location calculation to section_rel() kbuild: Disable GCOV for *.mod.o kbuild: Fix CFI failures with GCOV kbuild: make clean rule robust against too long argument error script: modpost: emit a warning when the description is missing kbuild: make modules_install copy modules.builtin(.modinfo) linux/export.h: rename 'sec' argument to 'license' modpost: show offset from symbol for section mismatch warnings modpost: merge two similar section mismatch warnings kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion modpost: use null string instead of NULL pointer for default namespace modpost: squash sym_update_namespace() into sym_add_exported() ...
2023-06-10kernel-doc: don't let V=1 change outcomeJohannes Berg
The kernel-doc script currently reports a number of issues only in "verbose" mode, but that's initialized from V=1 (via KBUILD_VERBOSE), so if you use KDOC_WERROR=1 then adding V=1 might actually break the build. This is rather unexpected. Change kernel-doc to not change its behaviour wrt. errors (or warnings) when verbose mode is enabled, but rather add separate warning flags (and -Wall) for it. Allow enabling those flags via environment/make variables in the kernel's build system for easier user use, but to not have to parse them in the script itself. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-06-05docs: scripts: kernel-doc: accept bitwise negation like ~@varMark Rutland
In some cases we'd like to indicate the bitwise negation of a parameter, e.g. ~@var This will be helpful for describing the atomic andnot operations, where we'd like to write comments of the form: Atomically updates @v to (@v & ~@i) Which kernel-doc currently transforms to: Atomically updates **v** to (**v** & ~**i**) Rather than the preferable form: Atomically updates **v** to (**v** & **~i**) This is similar to what we did for '!@var' in commit: ee2aa7590398 ("scripts: kernel-doc: accept negation like !@var") This patch follows the same pattern that commit used to permit a '!' prefix on a param ref, allowing a '~' prefix on a param ref, cuasing kernel-doc to generate the preferred form above. Suggested-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230605070124.3741859-25-mark.rutland@arm.com
2023-02-26Merge tag 'kbuild-v6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Change V=1 option to print both short log and full command log - Allow V=1 and V=2 to be combined as V=12 - Make W=1 detect wrong .gitignore files - Tree-wide cleanups for unused command line arguments passed to Clang - Stop using -Qunused-arguments with Clang - Make scripts/setlocalversion handle only correct release tags instead of any arbitrary annotated tag - Create Debian and RPM source packages without cleaning the source tree - Various cleanups for packaging * tag 'kbuild-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (74 commits) kbuild: rpm-pkg: remove unneeded KERNELRELEASE from modules/headers_install docs: kbuild: remove description of KBUILD_LDS_MODULE .gitattributes: use 'dts' diff driver for *.dtso files kbuild: deb-pkg: improve the usability of source package kbuild: deb-pkg: fix binary-arch and clean in debian/rules kbuild: tar-pkg: use tar rules in scripts/Makefile.package kbuild: make perf-tar*-src-pkg work without relying on git kbuild: deb-pkg: switch over to source format 3.0 (quilt) kbuild: deb-pkg: make .orig tarball a hard link if possible kbuild: deb-pkg: hide KDEB_SOURCENAME from Makefile kbuild: srcrpm-pkg: create source package without cleaning kbuild: rpm-pkg: build binary packages from source rpm kbuild: deb-pkg: create source package without cleaning kbuild: add a tool to list files ignored by git Documentation/llvm: add Chimera Linux, Google and Meta datacenters setlocalversion: use only the correct release tag for git-describe setlocalversion: clean up the construction of version output .gitignore: ignore *.cover and *.mbx kbuild: remove --include-dir MAKEFLAG from top Makefile kbuild: fix trivial typo in comment ...
2023-01-31scripts: kernel-doc: Remove workaround for @param... syntaxJonathan Neuschäfer
Commit 43756e347f21 ("scripts/kernel-doc: Add support for named variable macro arguments") improved how named variable macro arguments are handled, and changed how they are documented in kerneldoc comments from "@param...", to "@param", deprecating the old syntax. All users of the old syntax have since been converted, so this commit finally removes support for it. The output of "make htmldocs" is the same with and without this commit. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20230129150435.1510400-1-j.neuschaefer@gmx.net Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-22kbuild: do not print extra logs for V=2Masahiro Yamada
Some scripts increase the verbose level when V=1, but others when not V=0. I think the former is correct because V=2 is not a log level but a switch to print the reason for rebuilding. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-12-14Merge tag 'hardening-v6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull kernel hardening updates from Kees Cook: - Convert flexible array members, fix -Wstringop-overflow warnings, and fix KCFI function type mismatches that went ignored by maintainers (Gustavo A. R. Silva, Nathan Chancellor, Kees Cook) - Remove the remaining side-effect users of ksize() by converting dma-buf, btrfs, and coredump to using kmalloc_size_roundup(), add more __alloc_size attributes, and introduce full testing of all allocator functions. Finally remove the ksize() side-effect so that each allocation-aware checker can finally behave without exceptions - Introduce oops_limit (default 10,000) and warn_limit (default off) to provide greater granularity of control for panic_on_oops and panic_on_warn (Jann Horn, Kees Cook) - Introduce overflows_type() and castable_to_type() helpers for cleaner overflow checking - Improve code generation for strscpy() and update str*() kern-doc - Convert strscpy and sigphash tests to KUnit, and expand memcpy tests - Always use a non-NULL argument for prepare_kernel_cred() - Disable structleak plugin in FORTIFY KUnit test (Anders Roxell) - Adjust orphan linker section checking to respect CONFIG_WERROR (Xin Li) - Make sure siginfo is cleared for forced SIGKILL (haifeng.xu) - Fix um vs FORTIFY warnings for always-NULL arguments * tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (31 commits) ksmbd: replace one-element arrays with flexible-array members hpet: Replace one-element array with flexible-array member um: virt-pci: Avoid GCC non-NULL warning signal: Initialize the info in ksignal lib: fortify_kunit: build without structleak plugin panic: Expose "warn_count" to sysfs panic: Introduce warn_limit panic: Consolidate open-coded panic_on_warn checks exit: Allow oops_limit to be disabled exit: Expose "oops_count" to sysfs exit: Put an upper limit on how often we can oops panic: Separate sysctl logic from CONFIG_SMP mm/pgtable: Fix multiple -Wstringop-overflow warnings mm: Make ksize() a reporting-only function kunit/fortify: Validate __alloc_size attribute results drm/sti: Fix return type of sti_{dvo,hda,hdmi}_connector_mode_valid() drm/fsl-dcu: Fix return type of fsl_dcu_drm_connector_mode_valid() driver core: Add __alloc_size hint to devm allocators overflow: Introduce overflows_type() and castable_to_type() coredump: Proactively round up to kmalloc bucket size ...
2022-12-14Merge tag 'for-linus-iommufd' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd Pull iommufd implementation from Jason Gunthorpe: "iommufd is the user API to control the IOMMU subsystem as it relates to managing IO page tables that point at user space memory. It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO container) which is the VFIO specific interface for a similar idea. We see a broad need for extended features, some being highly IOMMU device specific: - Binding iommu_domain's to PASID/SSID - Userspace IO page tables, for ARM, x86 and S390 - Kernel bypassed invalidation of user page tables - Re-use of the KVM page table in the IOMMU - Dirty page tracking in the IOMMU - Runtime Increase/Decrease of IOPTE size - PRI support with faults resolved in userspace Many of these HW features exist to support VM use cases - for instance the combination of PASID, PRI and Userspace IO Page Tables allows an implementation of DMA Shared Virtual Addressing (vSVA) within a guest. Dirty tracking enables VM live migration with SRIOV devices and PASID support allow creating "scalable IOV" devices, among other things. As these features are fundamental to a VM platform they need to be uniformly exposed to all the driver families that do DMA into VMs, which is currently VFIO and VDPA" For more background, see the extended explanations in Jason's pull request: https://lore.kernel.org/lkml/Y5dzTU8dlmXTbzoJ@nvidia.com/ * tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (62 commits) iommufd: Change the order of MSI setup iommufd: Improve a few unclear bits of code iommufd: Fix comment typos vfio: Move vfio group specific code into group.c vfio: Refactor dma APIs for emulated devices vfio: Wrap vfio group module init/clean code into helpers vfio: Refactor vfio_device open and close vfio: Make vfio_device_open() truly device specific vfio: Swap order of vfio_device_container_register() and open_device() vfio: Set device->group in helper function vfio: Create wrappers for group register/unregister vfio: Move the sanity check of the group to vfio_create_group() vfio: Simplify vfio_create_group() iommufd: Allow iommufd to supply /dev/vfio/vfio vfio: Make vfio_container optionally compiled vfio: Move container related MODULE_ALIAS statements into container.c vfio-iommufd: Support iommufd for emulated VFIO devices vfio-iommufd: Support iommufd for physical VFIO devices vfio-iommufd: Allow iommufd to be used in place of a container fd vfio: Use IOMMU_CAP_ENFORCE_CACHE_COHERENCY for vfio_file_enforced_coherent() ...
2022-11-29scripts/kernel-doc: support EXPORT_SYMBOL_NS_GPL() with -exportJason Gunthorpe
Parse EXPORT_SYMBOL_NS_GPL() in addition to EXPORT_SYMBOL_GPL() for use with the -export flag. Link: https://lore.kernel.org/r/4-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-10-28string: Rewrite and add more kern-doc for the str*() functionsKees Cook
While there were varying degrees of kern-doc for various str*()-family functions, many needed updating and clarification, or to just be entirely written. Update (and relocate) existing kern-doc and add missing functions, sadly shaking my head at how many times I have written "Do not use this function". Include the results in the core kernel API doc. Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Andy Shevchenko <andy@kernel.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-hardening@vger.kernel.org Tested-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/lkml/9b0cf584-01b3-3013-b800-1ef59fe82476@gmail.com Signed-off-by: Kees Cook <keescook@chromium.org>
2022-10-18docs: improve the HTML formatting of kerneldoc commentsJonathan Corbet
Make a few changes to cause functions documented by kerneldoc to stand out better in the rendered documentation. Specifically, change kernel-doc to put the description section into a ".. container::" section, then add a bit of CSS to indent that section relative to the function prototype (or struct or enum definition). Tweak a few other CSS parameters while in the neighborhood to improve the formatting. Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-06-13scripts: kernel-doc: Always increment warnings counterNiklas Söderlund
Some warnings do not increment the warnings counter making the behavior of running kernel-doc with -Werror unlogical as some warnings will be generated but not treated as errors. Fix this by creating a helper function that always incrementing the warnings counter every time a warning is emitted. There is one location in get_sphinx_version() where a warning is not touched as it concerns the execution environment of the kernel-doc and not the documentation being processed. Incrementing the counter only have effect when running kernel-doc in either verbose mode (-v or environment variable KBUILD_VERBOSE) or when treating warnings as errors (-Werror or environment variable KDOC_WERROR). In both cases the number of warnings printed is printed to stderr and for the later the exit code of kernel-doc is non-zero if warnings where encountered. Simple test case to demo one of the warnings, $ cat test.c /** * foo() - Description */ int bar(); # Without this change $ ./scripts/kernel-doc -Werror -none test.c test.c:4: warning: expecting prototype for foo(). Prototype was for bar() instead # With this change $ ./scripts/kernel-doc -Werror -none test.c test.c:4: warning: expecting prototype for foo(). Prototype was for bar() instead 1 warnings as Errors Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com> Link: https://lore.kernel.org/r/20220613090510.3088294-1-niklas.soderlund@corigine.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-28scripts/kernel-doc: change the line number meta infoMauro Carvalho Chehab
In order to make it more standard and ReST compatible, change the meta-tag used with --enable-lineno from: #define LINENO to .. LINENO In practice, no functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org> Link: https://lore.kernel.org/r/40725032b5a4a33db740bf1de397523af958ff8a.1648290305.git.mchehab@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24docs: scripts/kernel-doc: Detect absence of FILE argAkira Yokosawa
Currently, when there is no FILE argument following a switch such as -man, -rst, or -none, kernel-doc exits with a warning from perl (long msg folded): Use of uninitialized value $ARGV[0] in pattern match (m//) at ./scripts/kernel-doc line 438. , which is unhelpful. Improve the behavior by adding a check at the bottom of parsing loop. If the argument is absent, display help text and exit with the code of 1 (via usage()). Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/7b136049-a3ba-0eb5-8717-364d773ff914@gmail.com [jc: reworked to fix conflict with pod patches] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Refresh the copyright linesTomasz Warniełło
I wanted to clean up these lines, but in the end decided not to touch the old ones and just add my own about POD. I'll leave the cleanup for lawyers. Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-12-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Drop obsolete commentsTomasz Warniełło
What for? To improve the script maintainability. 1. License As stated by Jonathan Corbet in the reply to my version 1, the SPDX line is enough. 2. The to-do list comment As suggested by Jonathan Corbet in reply to my version 3, this section doesn't need to be transitioned. And so it is removed for clarity. 3. The historical changelog comments As suggested by Jonathan Corbet in a reply to v3, this section can go. I wanted to keep it, but since it doesn't contain copyright notices, let's just have it clean and simple. 4. The "format of comments" comment block As suggested by Jani Nikula in a reply to my first version of this transformation, Documentation/doc-guide/kernel-doc.rst can serve as the information hub for comment formatting. The section DESCRIPTION already points there, so the original comment block can just be removed. Suggested-by: Jonathan Corbet <corbet@lwn.net> Suggested-by: Jani Nikula <jani.nikula@linux.intel.com> Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-11-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Replace the usage functionTomasz Warniełło
Aim: unified POD, user more satisfied, script better structured You can see the results with: $ scripts/kernel-doc -help Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-10-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the "Other parameters" subsection of OPTIONSTomasz Warniełło
Aim: unified POD, user more satisfied, script better structured Notes: - The -help token is added. - The entries are sorted alphbetically. Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-9-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the "Output selection modifiers" subsection ↵Tomasz Warniełło
of OPTIONS Aim: unified POD, user more satisfied, script better structured A subsection "reStructuredText only" is added for -enable-lineno. Other notes: - paragraphing correction Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-8-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the "Output selection" subsection of OPTIONSTomasz Warniełło
Aim: unified POD, user more satisfied, script better structured The plurals in -function and -nosymbol are corrected to singulars. That's how the script works now. I think this describes the syntax better. The plurar suggests multiple FILE arguments might be possible. So this seems more coherent. Other notes: - paragraphing correction - article correction Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-7-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the "Output format selection modifier" ↵Tomasz Warniełło
subsection of OPTIONS Aim: unified POD, user more happy This section is renamed to "Output format modifiers" to make it simple. To make it even more simple, a subsection is added: "reStructuredText only". Other notes: - paragraphing correction - article correction Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-6-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the "Output format selection" subsection of ↵Tomasz Warniełło
OPTIONS Another step in the direction of a uniform POD documentation, which will make users happier. Options land at the end of the script, not to clutter the file top. The default output format is corrected to rst. That's what it is now. A POD delimiting comment is added to the script head, which improves the script logical structure. Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-5-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Translate the DESCRIPTION sectionTomasz Warniełło
Transition the description section into POD. This is one of the standard documentation sections. This adjustment makes the section available for POD and makes it look better. Notes: - an article addition - paragraphing correction Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-4-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Relink argument parsing error handling to pod2usageTomasz Warniełło
The former usage function is substituted, although not as the -h and -help parameter handler yet. Purpose: Use Pod::Usage to handle documentation printing in an integrated way. Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-3-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24scripts: kernel-doc: Add the basic POD sectionsTomasz Warniełło
The NAME section provides the doc title, while SYNOPSIS contains the basic syntax and usage description, which will be printed in the help document and in the error output produced on wrong script usage. The rationale is to give users simple and succinct enlightment, at the same time structuring the script internally for the maintainers. In the synopsis, Rst-only options are grouped around rst, and the rest is arranged as in the OPTIONS subsections (yet to be translated into POD, check at the end of the series). The third of the basic sections, DESCRIPTION, is added separately. Signed-off-by: Tomasz Warniełło <tomasz.warniello@gmail.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Disliked-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/20220218181628.1411551-2-tomasz.warniello@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-02Merge tag 'docs-5.16' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This is a relatively unexciting cycle for documentation. - Some small scripts/kerneldoc fixes - More Chinese translation work, but at a much reduced rate. - The tip-tree maintainer's handbook ...plus the usual array of build fixes, typo fixes, etc" * tag 'docs-5.16' of git://git.lwn.net/linux: (53 commits) kernel-doc: support DECLARE_PHY_INTERFACE_MASK() docs/zh_CN: add core-api xarray translation docs/zh_CN: add core-api assoc_array translation speakup: Fix typo in documentation "boo" -> "boot" docs: submitting-patches: make section about the Link: tag more explicit docs: deprecated.rst: Clarify open-coded arithmetic with literals scripts: documentation-file-ref-check: fix bpf selftests path scripts: documentation-file-ref-check: ignore hidden files coding-style.rst: trivial: fix location of driver model macros docs: f2fs: fix text alignment docs/zh_CN add PCI pci.rst translation docs/zh_CN add PCI index.rst translation docs: translations: zh_CN: memory-hotplug.rst: fix a typo docs: translations: zn_CN: irq-affinity.rst: add a missing extension block: add documentation for inflight scripts: kernel-doc: Ignore __alloc_size() attribute docs: pdfdocs: Adjust \headheight for fancyhdr docs: UML: user_mode_linux_howto_v2 edits docs: use the lore redirector everywhere docs: proc.rst: mountinfo: align columns ...
2021-11-01kernel-doc: support DECLARE_PHY_INTERFACE_MASK()Randy Dunlap
Support the DECLARE_PHY_INTERFACE_MASK() macro that is used to declare a bitmap by converting the macro to DECLARE_BITMAP(), as has been done for the __ETHTOOL_DECLARE_LINK_MODE_MASK() macro. This fixes a 'make htmldocs' warning: include/linux/phylink.h:82: warning: Function parameter or member 'DECLARE_PHY_INTERFACE_MASK(supported_interfaces' not described in 'phylink_config' that was introduced by commit 38c310eb46f5 ("net: phylink: add MAC phy_interface_t bitmap") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Russell King (Oracle) <linux@armlinux.org.uk> Link: https://lore.kernel.org/r/45934225-7942-4326-f883-a15378939db9@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-10-18stddef: Introduce DECLARE_FLEX_ARRAY() helperKees Cook
There are many places where kernel code wants to have several different typed trailing flexible arrays. This would normally be done with multiple flexible arrays in a union, but since GCC and Clang don't (on the surface) allow this, there have been many open-coded workarounds, usually involving neighboring 0-element arrays at the end of a structure. For example, instead of something like this: struct thing { ... union { struct type1 foo[]; struct type2 bar[]; }; }; code works around the compiler with: struct thing { ... struct type1 foo[0]; struct type2 bar[]; }; Another case is when a flexible array is wanted as the single member within a struct (which itself is usually in a union). For example, this would be worked around as: union many { ... struct { struct type3 baz[0]; }; }; These kinds of work-arounds cause problems with size checks against such zero-element arrays (for example when building with -Warray-bounds and -Wzero-length-bounds, and with the coming FORTIFY_SOURCE improvements), so they must all be converted to "real" flexible arrays, avoiding warnings like this: fs/hpfs/anode.c: In function 'hpfs_add_sector_to_btree': fs/hpfs/anode.c:209:27: warning: array subscript 0 is outside the bounds of an interior zero-length array 'struct bplus_internal_node[0]' [-Wzero-length-bounds] 209 | anode->btree.u.internal[0].down = cpu_to_le32(a); | ~~~~~~~~~~~~~~~~~~~~~~~^~~ In file included from fs/hpfs/hpfs_fn.h:26, from fs/hpfs/anode.c:10: fs/hpfs/hpfs.h:412:32: note: while referencing 'internal' 412 | struct bplus_internal_node internal[0]; /* (internal) 2-word entries giving | ^~~~~~~~ drivers/net/can/usb/etas_es58x/es58x_fd.c: In function 'es58x_fd_tx_can_msg': drivers/net/can/usb/etas_es58x/es58x_fd.c:360:35: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[]'} [-Wzero-length-bounds] 360 | tx_can_msg = (typeof(tx_can_msg))&es58x_fd_urb_cmd->raw_msg[msg_len]; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from drivers/net/can/usb/etas_es58x/es58x_core.h:22, from drivers/net/can/usb/etas_es58x/es58x_fd.c:17: drivers/net/can/usb/etas_es58x/es58x_fd.h:231:6: note: while referencing 'raw_msg' 231 | u8 raw_msg[0]; | ^~~~~~~ However, it _is_ entirely possible to have one or more flexible arrays in a struct or union: it just has to be in another struct. And since it cannot be alone in a struct, such a struct must have at least 1 other named member -- but that member can be zero sized. Wrap all this nonsense into the new DECLARE_FLEX_ARRAY() in support of having flexible arrays in unions (or alone in a struct). As with struct_group(), since this is needed in UAPI headers as well, implement the core there, with a non-UAPI wrapper. Additionally update kernel-doc to understand its existence. https://github.com/KSPP/linux/issues/137 Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2021-10-12scripts: kernel-doc: Ignore __alloc_size() attributeKees Cook
Fixes "Compiler Attributes: add __alloc_size() for better bounds checking" so that the __alloc_size() macro is ignored for function prototypes when generating kerndoc. Avoids warnings like: ./include/linux/slab.h:662: warning: Function parameter or member '1' not described in '__alloc_size' ./include/linux/slab.h:662: warning: Function parameter or member '2' not described in '__alloc_size' ./include/linux/slab.h:662: warning: expecting prototype for kcalloc(). Prototype was for __alloc_size() instead Suggested-by: Matthew Wilcox <willy@infradead.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20211011180650.3603988-1-keescook@chromium.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-25stddef: Introduce struct_group() helper macroKees Cook
Kernel code has a regular need to describe groups of members within a structure usually when they need to be copied or initialized separately from the rest of the surrounding structure. The generally accepted design pattern in C is to use a named sub-struct: struct foo { int one; struct { int two; int three, four; } thing; int five; }; This would allow for traditional references and sizing: memcpy(&dst.thing, &src.thing, sizeof(dst.thing)); However, doing this would mean that referencing struct members enclosed by such named structs would always require including the sub-struct name in identifiers: do_something(dst.thing.three); This has tended to be quite inflexible, especially when such groupings need to be added to established code which causes huge naming churn. Three workarounds exist in the kernel for this problem, and each have other negative properties. To avoid the naming churn, there is a design pattern of adding macro aliases for the named struct: #define f_three thing.three This ends up polluting the global namespace, and makes it difficult to search for identifiers. Another common work-around in kernel code avoids the pollution by avoiding the named struct entirely, instead identifying the group's boundaries using either a pair of empty anonymous structs of a pair of zero-element arrays: struct foo { int one; struct { } start; int two; int three, four; struct { } finish; int five; }; struct foo { int one; int start[0]; int two; int three, four; int finish[0]; int five; }; This allows code to avoid needing to use a sub-struct named for member references within the surrounding structure, but loses the benefits of being able to actually use such a struct, making it rather fragile. Using these requires open-coded calculation of sizes and offsets. The efforts made to avoid common mistakes include lots of comments, or adding various BUILD_BUG_ON()s. Such code is left with no way for the compiler to reason about the boundaries (e.g. the "start" object looks like it's 0 bytes in length), making bounds checking depend on open-coded calculations: if (length > offsetof(struct foo, finish) - offsetof(struct foo, start)) return -EINVAL; memcpy(&dst.start, &src.start, offsetof(struct foo, finish) - offsetof(struct foo, start)); However, the vast majority of places in the kernel that operate on groups of members do so without any identification of the grouping, relying either on comments or implicit knowledge of the struct contents, which is even harder for the compiler to reason about, and results in even more fragile manual sizing, usually depending on member locations outside of the region (e.g. to copy "two" and "three", use the start of "four" to find the size): BUILD_BUG_ON((offsetof(struct foo, four) < offsetof(struct foo, two)) || (offsetof(struct foo, four) < offsetof(struct foo, three)); if (length > offsetof(struct foo, four) - offsetof(struct foo, two)) return -EINVAL; memcpy(&dst.two, &src.two, length); In order to have a regular programmatic way to describe a struct region that can be used for references and sizing, can be examined for bounds checking, avoids forcing the use of intermediate identifiers, and avoids polluting the global namespace, introduce the struct_group() macro. This macro wraps the member declarations to create an anonymous union of an anonymous struct (no intermediate name) and a named struct (for references and sizing): struct foo { int one; struct_group(thing, int two; int three, four; ); int five; }; if (length > sizeof(src.thing)) return -EINVAL; memcpy(&dst.thing, &src.thing, length); do_something(dst.three); There are some rare cases where the resulting struct_group() needs attributes added, so struct_group_attr() is also introduced to allow for specifying struct attributes (e.g. __align(x) or __packed). Additionally, there are places where such declarations would like to have the struct be tagged, so struct_group_tagged() is added. Given there is a need for a handful of UAPI uses too, the underlying __struct_group() macro has been defined in UAPI so it can be used there too. To avoid confusing scripts/kernel-doc, hide the macro from its struct parsing. Co-developed-by: Keith Packard <keithp@keithp.com> Signed-off-by: Keith Packard <keithp@keithp.com> Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://lore.kernel.org/lkml/20210728023217.GC35706@embeddedor Enhanced-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/lkml/41183a98-bdb9-4ad6-7eab-5a7292a6df84@rasmusvillemoes.dk Enhanced-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/lkml/1d9a2e6df2a9a35b2cdd50a9a68cac5991e7e5f0.camel@intel.com Enhanced-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://lore.kernel.org/lkml/YQKa76A6XuFqgM03@phenom.ffwll.local Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2021-08-12scripts/kernel-doc: Override -Werror from KCFLAGS with KDOC_WERRORLaurent Pinchart
Since commit 2c12c8103d8f ("scripts/kernel-doc: optionally treat warnings as errors"), the kernel-doc script will treat warnings as errors when one of the following conditions is true: - The KDOC_WERROR environment variable is non-zero - The KCFLAGS environment variable contains -Werror - The -Werror parameter is passed to kernel-doc Checking KCFLAGS for -Werror allows piggy-backing on the C compiler error handling. However, unlike the C compiler, kernel-doc has no provision for -Wno-error. This makes compiling the kernel with -Werror (to catch regressions) and W=1 (to enable more checks) always fail, without the same possibility as offered by the C compiler to treating some selected warnings as warnings despite the global -Werror setting. To fix this, evaluate KDOC_WERROR after KCFLAGS, which allows disabling the warnings-as-errors behaviour of kernel-doc selectively by setting KDOC_WERROR=0. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Link: https://lore.kernel.org/r/20210730225401.4401-1-laurent.pinchart+renesas@ideasonboard.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-17scripts: kernel-doc: reduce repeated regex expressions into variablesAditya Srivastava
There are some regex expressions in the kernel-doc script, which are used repeatedly in the script. Reduce such expressions into variables, which can be used everywhere. A quick manual check found that no errors and warnings were added/removed in this process. Suggested-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Aditya Srivastava <yashsri421@gmail.com> Link: https://lore.kernel.org/r/20210514144244.25341-1-yashsri421@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-27kernel-doc: Add support for __deprecatedMatthew Wilcox
The current linux-next tree has a new error: ./Documentation/gpu/drm-mm:445: ./drivers/gpu/drm/drm_prime.c:994: WARNING: Error in declarator or parameters Invalid C declaration: Expecting "(" in parameters. [error at 17] int __deprecated drm_prime_sg_to_page_array (struct sg_table *sgt, struct page **pages, int max_entries) -----------------^ While we might consider that documenting a deprecated interface is not necessarily best practice, removing the error is easy. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20210427114828.GY235567@casper.infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-15scripts: kernel-doc: improve parsing for kernel-doc comments syntaxAditya Srivastava
Currently kernel-doc does not identify some cases of probable kernel doc comments, for e.g. pointer used as declaration type for identifier, space separated identifier, etc. Some example of these cases in files can be: i)" * journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure" in fs/jbd2/journal.c ii) "* dget, dget_dlock - get a reference to a dentry" in include/linux/dcache.h iii) " * DEFINE_SEQLOCK(sl) - Define a statically allocated seqlock_t" in include/linux/seqlock.h Also improve identification for non-kerneldoc comments. For e.g., i) " * The following functions allow us to read data using a swap map" in kernel/power/swap.c does follow the kernel-doc like syntax, but the content inside does not adheres to the expected format. Improve parsing by adding support for these probable attempts to write kernel-doc comment. Suggested-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/lkml/87mtujktl2.fsf@meer.lwn.net Signed-off-by: Aditya Srivastava <yashsri421@gmail.com> Link: https://lore.kernel.org/r/20210414192529.9080-1-yashsri421@gmail.com [ jc: fixed some line-length issues ] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-29scripts: kernel-doc: add warning for comment not following kernel-doc syntaxAditya Srivastava
Currently, kernel-doc start parsing the comment as a kernel-doc comment if it starts with '/**', but does not take into account if the content inside the comment too, adheres with the expected format. This results in unexpected and unclear warnings for the user. E.g., running scripts/kernel-doc -none mm/memcontrol.c emits: "mm/memcontrol.c:961: warning: expecting prototype for do not fallback to current(). Prototype was for get_mem_cgroup_from_current() instead" Here kernel-doc parses the corresponding comment as a kernel-doc comment and expects prototype for it in the next lines, and as a result causing this warning. Provide a clearer warning message to the users regarding the same, if the content inside the comment does not follow the kernel-doc expected format. Signed-off-by: Aditya Srivastava <yashsri421@gmail.com> Link: https://lore.kernel.org/r/20210329092945.13152-1-yashsri421@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-26docs: kernel-doc: properly recognize parameter lines with colonsJonathan Corbet
The previous attempt to properly handle literal blocks broke parsing of parameter lines containing colons; fix it by tweaking the regex to specifically exclude the "::" pattern while accepting lines containing colons in general. Add a little documentation to the regex while in the neighborhood. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Fixes: 8d295fbad687 ("kernel-doc: better handle '::' sequences") Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-25kernel-doc: better handle '::' sequencesMauro Carvalho Chehab
Right now, if one of the following headers end with a '::', the kernel-doc script will do the wrong thing: description|context|returns?|notes?|examples? The real issue is with examples, as people could try to write something like: example:: /* Some C code */ and this won't be properly evaluated. So, improve the regex to not catch '\w+::' regex for the above identifiers. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/2cf44cf1fa42588632735d4fbc8e84304bdc235f.1616696051.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>