Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
For self-hosted knots, clone URLs may differ based on your setup.
Pull Kbuild fixes from Masahiro Yamada:
- Fix RPM package build error caused by an incorrect locale setup
- Mark modules.weakdep as ghost in RPM package
- Fix the odd combination of -S and -c in stack protector scripts,
which is an error with the latest Clang
* tag 'kbuild-fixes-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: Fix '-S -c' in x86 stack protector scripts
kbuild: rpm-pkg: ghost modules.weakdep file
kbuild: rpm-pkg: Fix C locale setup
This simplifies the min_t() and max_t() macros by no longer making them
work in the context of a C constant expression.
That means that you can no longer use them for static initializers or
for array sizes in type definitions, but there were only a couple of
such uses, and all of them were converted (famous last words) to use
MIN_T/MAX_T instead.
Cc: David Laight <David.Laight@aculab.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After a recent change in clang to stop consuming all instances of '-S'
and '-c' [1], the stack protector scripts break due to the kernel's use
of -Werror=unused-command-line-argument to catch cases where flags are
not being properly consumed by the compiler driver:
$ echo | clang -o - -x c - -S -c -Werror=unused-command-line-argument
clang: error: argument unused during compilation: '-c' [-Werror,-Wunused-command-line-argument]
This results in CONFIG_STACKPROTECTOR getting disabled because
CONFIG_CC_HAS_SANE_STACKPROTECTOR is no longer set.
'-c' and '-S' both instruct the compiler to stop at different stages of
the pipeline ('-S' after compiling, '-c' after assembling), so having
them present together in the same command makes little sense. In this
case, the test wants to stop before assembling because it is looking at
the textual assembly output of the compiler for either '%fs' or '%gs',
so remove '-c' from the list of arguments to resolve the error.
All versions of GCC continue to work after this change, along with
versions of clang that do or do not contain the change mentioned above.
Cc: stable@vger.kernel.org
Fixes: 4f7fd4d7a791 ("[PATCH] Add the -fstack-protector option to the CFLAGS")
Fixes: 60a5317ff0f4 ("x86: implement x86_32 stack protector")
Link: https://github.com/llvm/llvm-project/commit/6461e537815f7fa68cef06842505353cf5600e9c [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Commit 3a7e02c040b1 ("minmax: avoid overly complicated constant
expressions in VM code") added the simpler MIN_T/MAX_T macros in order
to avoid some excessive expansion from the rather complicated regular
min/max macros.
The complexity of those macros stems from two issues:
(a) trying to use them in situations that require a C constant
expression (in static initializers and for array sizes)
(b) the type sanity checking
and MIN_T/MAX_T avoids both of these issues.
Now, in the whole (long) discussion about all this, it was pointed out
that the whole type sanity checking is entirely unnecessary for
min_t/max_t which get a fixed type that the comparison is done in.
But that still leaves min_t/max_t unnecessarily complicated due to
worries about the C constant expression case.
However, it turns out that there really aren't very many cases that use
min_t/max_t for this, and we can just force-convert those.
This does exactly that.
Which in turn will then allow for much simpler implementations of
min_t()/max_t(). All the usual "macros in all upper case will evaluate
the arguments multiple times" rules apply.
We should do all the same things for the regular min/max() vs MIN/MAX()
cases, but that has the added complexity of various drivers defining
their own local versions of MIN/MAX, so that needs another level of
fixes first.
Link: https://lore.kernel.org/all/b47fad1d0cf8449886ad148f8c013dae@AcuMS.aculab.com/
Cc: David Laight <David.Laight@aculab.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the same way as for other similar files, mark as ghost the new file
generated by depmod for configured weak dependencies for modules,
modules.weakdep, so that although it is not included in the package,
claim the ownership on it.
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull UBI and UBIFS updates from Richard Weinberger:
- Many fixes for power-cut issues by Zhihao Cheng
- Another ubiblock error path fix
- ubiblock section mismatch fix
- Misc fixes all over the place
* tag 'ubifs-for-linus-6.11-rc1-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubi: Fix ubi_init() ubiblock_exit() section mismatch
ubifs: add check for crypto_shash_tfm_digest
ubifs: Fix inconsistent inode size when powercut happens during appendant writing
ubi: block: fix null-pointer-dereference in ubiblock_create()
ubifs: fix kernel-doc warnings
ubifs: correct UBIFS_DFS_DIR_LEN macro definition and improve code clarity
mtd: ubi: Restore missing cleanup on ubi_init() failure path
ubifs: dbg_orphan_check: Fix missed key type checking
ubifs: Fix unattached inode when powercut happens in creating
ubifs: Fix space leak when powercut happens in linking tmpfile
ubifs: Move ui->data initialization after initializing security
ubifs: Fix adding orphan entry twice for the same inode
ubifs: Remove insert_dead_orphan from replaying orphan process
Revert "ubifs: ubifs_symlink: Fix memleak of inode->i_link in error path"
ubifs: Don't add xattr inode into orphan area
ubifs: Fix unattached xattr inode if powercut happens after deleting
mtd: ubi: avoid expensive do_div() on 32-bit machines
mtd: ubi: make ubi_class constant
ubi: eba: properly rollback inside self_check_eba
semicolon separation in LC_ALL is wrong. Either variable needs to be
exported before as a separate commit or set as part of the commit in the
beginning. Used second variant.
This fixes broken build on user's locale setup which makes 'date' binary
to produce invalid characters in rpm changelog (e.g. cs_CZ.UTF-8 'čec'):
$ make binrpm-pkg
GEN rpmbuild/SPECS/kernel.spec
rpmbuild -bb rpmbuild/SPECS/kernel.spec --define='_topdirlinux/rpmbuild' \
--target x86_64-linux --build-in-place --noprep --define='_smp_mflags \
%{nil}' $(rpm -q rpm >/dev/null 2>&1 || echo --nodeps)
Building target platforms: x86_64-linux
Building for target x86_64-linux
error: bad date in %changelog: St čec 24 2024 user <user@somehost>
make[2]: *** [scripts/Makefile.package:71: binrpm-pkg] Error 1
make[1]: *** [linux/Makefile:1546: binrpm-pkg] Error 2
make: *** [Makefile:224: __sub-make] Error 2
Fixes: 301c10908e42 ("kbuild: rpm-pkg: introduce a simple changelog section for kernel.spec")
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull turbostat updates from Len Brown:
- Enable turbostat extensions to add both perf and PMT (Intel
Platform Monitoring Technology) counters via the cmdline
- Demonstrate PMT access with built-in support for Meteor Lake's
Die C6 counter
* tag 'v6.11-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: version 2024.07.26
tools/power turbostat: Include umask=%x in perf counter's config
tools/power turbostat: Document PMT in turbostat.8
tools/power turbostat: Add MTL's PMT DC6 builtin counter
tools/power turbostat: Add early support for PMT counters
tools/power turbostat: Add selftests for added perf counters
tools/power turbostat: Add selftests for SMI, APERF and MPERF counters
tools/power turbostat: Move verbose counter messages to level 2
tools/power turbostat: Move debug prints from stdout to stderr
tools/power turbostat: Fix typo in turbostat.8
tools/power turbostat: Add perf added counter example to turbostat.8
tools/power turbostat: Fix formatting in turbostat.8
tools/power turbostat: Extend --add option with perf counters
tools/power turbostat: Group SMI counter with APERF and MPERF
tools/power turbostat: Add ZERO_ARRAY for zero initializing builtin array
tools/power turbostat: Replace enum rapl_source and cstate_source with counter_source
tools/power turbostat: Remove anonymous union from rapl_counter_info_t
tools/power/turbostat: Switch to new Intel CPU model defines
Since ubiblock_exit() is now called from an init function,
the __exit section no longer makes sense.
Cc: Ben Hutchings <bwh@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202407131403.wZJpd8n2-lkp@intel.com/
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Pull f2fs updates from Jaegeuk Kim:
"A pretty small update including mostly minor bug fixes in zoned
storage along with the large section support.
Enhancements:
- add support for FS_IOC_GETFSSYSFSPATH
- enable atgc dynamically if conditions are met
- use new ioprio Macro to get ckpt thread ioprio level
- remove unreachable lazytime mount option parsing
Bug fixes:
- fix null reference error when checking end of zone
- fix start segno of large section
- fix to cover read extent cache access with lock
- don't dirty inode for readonly filesystem
- allocate a new section if curseg is not the first seg in its zone
- only fragment segment in the same section
- truncate preallocated blocks in f2fs_file_open()
- fix to avoid use SSR allocate when do defragment
- fix to force buffered IO on inline_data inode
And some minor code clean-ups and sanity checks"
* tag 'f2fs-for-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (26 commits)
f2fs: clean up addrs_per_{inode,block}()
f2fs: clean up F2FS_I()
f2fs: use meta inode for GC of COW file
f2fs: use meta inode for GC of atomic file
f2fs: only fragment segment in the same section
f2fs: fix to update user block counts in block_operations()
f2fs: remove unreachable lazytime mount option parsing
f2fs: fix null reference error when checking end of zone
f2fs: fix start segno of large section
f2fs: remove redundant sanity check in sanity_check_inode()
f2fs: assign CURSEG_ALL_DATA_ATGC if blkaddr is valid
f2fs: fix to use mnt_{want,drop}_write_file replace file_{start,end}_wrtie
f2fs: clean up set REQ_RAHEAD given rac
f2fs: enable atgc dynamically if conditions are met
f2fs: fix to truncate preallocated blocks in f2fs_file_open()
f2fs: fix to cover read extent cache access with lock
f2fs: fix return value of f2fs_convert_inline_inode()
f2fs: use new ioprio Macro to get ckpt thread ioprio level
f2fs: fix to don't dirty inode for readonly filesystem
f2fs: fix to avoid use SSR allocate when do defragment
...
Pull CXL updates from Dave Jiang:
"Core:
- A CXL maturity map has been added to the documentation to detail
the current state of CXL enabling.
It provides the status of the current state of various CXL features
to inform current and future contributors of where things are and
which areas need contribution.
- A notifier handler has been added in order for a newly created CXL
memory region to trigger the abstract distance metrics calculation.
This should bring parity for CXL memory to the same level vs
hotplugged DRAM for NUMA abstract distance calculation. The
abstract distance reflects relative performance used for memory
tiering handling.
- An addition for XOR math has been added to address the CXL DPA to
SPA translation.
CXL address translation did not support address interleave math
with XOR prior to this change.
Fixes:
- Fix to address race condition in the CXL memory hotplug notifier
- Add missing MODULE_DESCRIPTION() for CXL modules
- Fix incorrect vendor debug UUID define
Misc:
- A warning has been added to inform users of an unsupported
configuration when mixing CXL VH and RCH/RCD hierarchies
- The ENXIO error code has been replaced with EBUSY for inject poison
limit reached via debugfs and cxl-test support
- Moving the PCI config read in cxl_dvsec_rr_decode() to avoid
unnecessary PCI config reads
- A refactor to a common struct for DRAM and general media CXL
events"
* tag 'cxl-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/core/pci: Move reading of control register to immediately before usage
cxl: Remove defunct code calculating host bridge target positions
cxl/region: Verify target positions using the ordered target list
cxl: Restore XOR'd position bits during address translation
cxl/core: Fold cxl_trace_hpa() into cxl_dpa_to_hpa()
cxl/test: Replace ENXIO with EBUSY for inject poison limit reached
cxl/memdev: Replace ENXIO with EBUSY for inject poison limit reached
cxl/acpi: Warn on mixed CXL VH and RCH/RCD Hierarchy
cxl/core: Fix incorrect vendor debug UUID define
Documentation: CXL Maturity Map
cxl/region: Simplify cxl_region_nid()
cxl/region: Support to calculate memory tier abstract distance
cxl/region: Fix a race condition in memory hotplug notifier
cxl: add missing MODULE_DESCRIPTION() macros
cxl/events: Use a common struct for DRAM and General Media events
Release 2024.07.26:
Enable turbostat extensions to add both perf and PMT
(Intel Platform Monitoring Technology) counters from the cmdline.
Demonstrate PMT access with built-in support for Meteor Lake's Die%c6 counter.
This commit:
Clean up white-space nits introduced since version 2024.05.10
Signed-off-by: Len Brown <len.brown@intel.com>
Add check for the return value of crypto_shash_tfm_digest() and return
the error if it fails in order to catch the error.
Fixes: 817aa094842d ("ubifs: support offline signed images")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull jfs updates from David Kleikamp:
"Folio conversion from Matthew Wilcox and a few various fixes"
* tag 'jfs-6.11' of github.com:kleikamp/linux-shaggy:
jfs: don't walk off the end of ealist
jfs: Fix shift-out-of-bounds in dbDiscardAG
jfs: Fix array-index-out-of-bounds in diFree
jfs: fix null ptr deref in dtInsertEntry
jfs: Remove use of folio error flag
fs: Remove i_blocks_per_page
jfs: Change metapage->page to metapage->folio
jfs: Convert force_metapage to use a folio
jfs: Convert inc_io to take a folio
jfs: Convert page_to_mp to folio_to_mp
jfs; Convert __invalidate_metapages to use a folio
jfs: Convert dec_io to take a folio
jfs: Convert drop_metapage and remove_metapage to take a folio
jfs; Convert release_metapage to use a folio
jfs: Convert insert_metapage() to take a folio
jfs: Convert __get_metapage to use a folio
jfs: Convert metapage_writepage to metapage_write_folio
jfs: Convert metapage_read_folio to use folio APIs
Introduce a new help addrs_per_page() to wrap common code
from addrs_per_inode() and addrs_per_block() for cleanup.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>