The imperative paradigm used to build vmlinux, extract some info from it
or perform some checks on it, and subsequently modify it again goes
against the declarative paradigm that is usually employed for defining
make rules.
In particular, the Makefile.postlink files that consume their input via
an output rule result in some dodgy logic in the decompressor makefiles
for RISC-V and x86, given that the vmlinux.relocs input file needed to
generate the arch-specific relocation tables may not exist or be out of
date, but cannot be constructed using the ordinary Make dependency based
rules, because the info needs to be extracted while vmlinux is in its
ephemeral, non-stripped form.
So instead, for architectures that require the static relocations that
are emitted into vmlinux when passing --emit-relocs to the linker, and
are subsequently stripped out again, introduce an intermediate vmlinux
target called vmlinux.unstripped, and organize the reset of the build
logic accordingly:
- vmlinux.unstripped is created only once, and not updated again
- build rules under arch/*/boot can depend on vmlinux.unstripped without
running the risk of the data disappearing or being out of date
- the final vmlinux generated by the build is not bloated with static
relocations that are never needed again after the build completes.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
In order to introduce an intermediate, non-stripped vmlinux build that
can be used by other build steps as an input, pass the output file name
to link-vmlinux.sh via its command line.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull rust fixes from Miguel Ojeda:
"Toolchain and infrastructure:
- Disallow BTF generation with Rust + LTO
- Improve rust-analyzer support
'kernel' crate:
- 'init' module: remove 'Zeroable' implementation for a couple types
that should not have it
- 'alloc' module: fix macOS failure in host test by satisfying POSIX
alignment requirement
- Add missing '\n's to 'pr_*!()' calls
And a couple other minor cleanups"
* tag 'rust-fixes-6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
scripts: generate_rust_analyzer: add uapi crate
scripts: generate_rust_analyzer: add missing include_dirs
scripts: generate_rust_analyzer: add missing macros deps
rust: Disallow BTF generation with Rust + LTO
rust: task: fix `SAFETY` comment in `Task::wake_up`
rust: workqueue: add missing newline to pr_info! examples
rust: sync: add missing newline in locked_by log example
rust: init: add missing newline to pr_info! calls
rust: error: add missing newline to pr_warn! calls
rust: docs: add missing newline to printing macro examples
rust: alloc: satisfy POSIX alignment requirement
rust: init: fix `Zeroable` implementation for `Option<NonNull<T>>` and `Option<KBox<T>>`
rust: remove leftover mentions of the `alloc` crate
Commit 5cc1247204 ("kbuild: add CONFIG_VMLINUX_MAP expert option")
mentioned that "the .map file can be rather large (several MB), and
that's a waste of space when one isn't interested in these things."
If that is the case, generating map files for the intermediate
tmp_vmlinux* files is also a waste of space. It is unlikely that
anyone would be interested in the .tmp_vmlinux*.map files.
This commit stops passing the -Map= option when linking the .tmp_vmlinux*
intermediates.
I also hard-coded the file name 'vmlinux.map' instead of ${output}.map
because a later commit will introduce vmlinux.unstripped but I want to
keep the current name of the map file.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
The .rodata.(cst|str)* sections are often resized during the final
linking and since these sections do not cover actual symbols there is
no need to include them in the modules.builtin.ranges data.
When these sections were included in processing and resizing occurred,
modules were reported with ranges that extended beyond their true end,
causing subsequent symbols (in address order) to be associated with
the wrong module.
Fixes: 5f5e734432 ("kbuild: generate offset range data for builtin modules")
Cc: stable@vger.kernel.org
Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Reviewed-by: Jack Vogel <jack.vogel@oracle.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Kernel build commands can sometimes be long, particularly when
cross-compiling, making them tedious to type and prone to mistypes.
This commit introduces bash completion support for common variables
and targets in Kbuild.
For installation instructions, please refer to the documentation in
Documentation/kbuild/bash-completion.rst.
The following examples demonstrate how this saves typing.
[Example 1] a long command line for cross-compiling
$ make A<TAB>
-> completes 'A' to 'ARCH='
$ make ARCH=<TAB>
-> displays all supported architectures
$ make ARCH=arm64 CR<TAB>
-> completes 'CR' to 'CROSS_COMPILE='
$ make ARCH=arm64 CROSS_COMPILE=<TAB>
-> displays installed toolchains
$ make ARCH=arm64 CROSS_COMPILE=aa<TAB>
-> completes 'CROSS_COMPILE=aa' to 'CROSS_COMPILE=aarch64-linux-gnu-'
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- def<TAB>
-> completes 'def' to 'defconfig'
[Example 2] a single build target
$ make f<TAB>
-> completes 'f' to 'fs/'
$ make fs/<TAB>
-> displays objects and sub-directories in fs/
$ make fs/xf<TAB>
-> completes 'fs/xf' to 'fs/xfs/'
$ make fs/xfs/l<TAB>
-> completes 'fs/xfs/l' to 'fs/xfs/libxfs/xfs_'
$ make fs/xfs/libxfs/xfs_g<TAB>
-> completes 'fs/xfs/libxfs/xfs_g' to 'fs/xfs/libxfs/xfs_group.o'
This does not aim to provide a complete list of variables and targets,
as there are too many. However, it covers variables and targets used
in common scenarios, and I hope this is useful enough.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Tested-by: Nicolas Schier <n.schier@avm.de>
The script previously assumed --file was always the first argument,
which caused issues when it appeared later. This patch updates the
parsing logic to scan all arguments to find --file, sets the config
file correctly, and resets the argument list with the remaining
commands.
It also fixes --refresh to respect --file by passing KCONFIG_CONFIG=$FN
to make oldconfig.
Signed-off-by: Seyediman Seyedarab <imandevel@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Without this dependency it's really puzzling when we bisect for a "bad"
commit in a series of sorttable change: when "git bisect" switches to
another commit, "make" just does nothing to vmlinux.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Fix follow warning when 'make ARCH=loongarch64 bindeb-pkg':
** ** ** WARNING ** ** **
Your architecture doesn't have its equivalent
Debian userspace architecture defined!
Falling back to the current host architecture (loong64).
Please add support for loongarch64 to ./scripts/package/mkdebian ...
Reported-by: Shiwei Liu <liushiwei@anheng.com.cn>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The -fzero-init-padding-bits=all option is not a warning flag, so
defining it in scripts/Makefile.extrawarn is inconsistent.
Move it to the top-level Makefile for consistency.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
The RPM packaging tools like to make sure that all packaged python
scripts have version-unambiguous shebangs. Be more specific about the
desired python version in a couple of places to avoid having to disable
these checks in make rpm-pkg.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Introduce `rustc-min-version` support function that mimics
`{gcc,clang}-min-version` ones, following commit 88b61e3bff
("Makefile.compiler: replace cc-ifversion with compiler-specific macros").
In addition, use it in the first use case we have in the kernel (which
was done independently to minimize the changes needed for the fix).
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Fiona Behrens <me@Kloenk.dev>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The logic to retrieve the basename appears multiple times.
Factor out the common pattern into a helper function.
I copied kbasename() from include/linux/string.h and renamed it
to get_basename().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
When conf_read_simple() is called with S_DEF_AUTO, it is meant to read
previous symbol values from include/config/auto.conf to determine which
include/config/* files should be touched.
This process should not modify the current symbol status in any way.
However, conf_touch_deps() currently invalidates all symbol values and
recalculates them, which is totally unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Since commit 9564a8cf42 ("Kbuild: fix # escaping in .cmd files for
future Make"), '#' in the build command is replaced with $(pound) rather
than '\#'.
Calling .replace(r'\#', '#') is only necessary when this tool is used
to parse .*.cmd files generated by Linux 4.16 or earlier, which is
unlikely to happen.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Commit f77bf01425 ("kbuild: introduce ccflags-y, asflags-y and
ldflags-y") deprecated these in 2007. The migration should have been
completed by now.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.14-rc6).
Conflicts:
tools/testing/selftests/drivers/net/ping.py
75cc19c8ff ("selftests: drv-net: add xdp cases for ping.py")
de94e86974 ("selftests: drv-net: store addresses in dict indexed by ipver")
https://lore.kernel.org/netdev/20250311115758.17a1d414@canb.auug.org.au/
net/core/devmem.c
a70f891e0f ("net: devmem: do not WARN conditionally after netdev_rx_queue_restart()")
1d22d3060b ("net: drop rtnl_lock for queue_mgmt operations")
https://lore.kernel.org/netdev/20250313114929.43744df1@canb.auug.org.au/
Adjacent changes:
tools/testing/selftests/net/Makefile
6f50175cca ("selftests: Add IPv6 link-local address generation tests for GRE devices.")
2e5584e0f9 ("selftests/net: expand cmsg_ipv6.sh with ipv4")
drivers/net/ethernet/broadcom/bnxt/bnxt.c
661958552e ("eth: bnxt: do not use BNXT_VNIC_NTUPLE unconditionally in queue restart logic")
fe96d717d3 ("bnxt_en: Extend queue stop/start for TX rings")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Both get_feat.pl and list-arch.sh use uname -m to get the machine hardware
name to figure out the current architecture if no architecture is specified
with a command line option.
This doesn't work for s390, since for 64 bit kernels the hardware name is
s390x, while the architecture name within the kernel, as well as in all
feature files is s390.
Therefore substitute s390x with s390 similar to what is already done for
x86_64 and i386.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250312155219.3597768-1-hca@linux.ibm.com
Commit 8c4555ccc5 ("scripts: add `generate_rust_analyzer.py`")
specified OBJTREE for the bindings crate, and `source.include_dirs` for
the kernel crate, likely in an attempt to support out-of-source builds
for those crates where the generated files reside in `objtree` rather
than `srctree`. This was insufficient because both bits of configuration
are required for each crate; the result is that rust-analyzer is unable
to resolve generated files for either crate in an out-of-source build.
[ Originally we were not using `OBJTREE` in the `kernel` crate, but
we did pass the variable anyway, so conceptually it could have been
there since then.
Regarding `include_dirs`, it started in `kernel` before being in
mainline because we included the bindings directly there (i.e.
there was no `bindings` crate). However, when that crate got
created, we moved the `OBJTREE` there but not the `include_dirs`.
Nowadays, though, we happen to need the `include_dirs` also in
the `kernel` crate for `generated_arch_static_branch_asm.rs` which
was not there back then -- Tamir confirms it is indeed required
for that reason. - Miguel ]
Add the missing bits to improve the developer experience.
Fixes: 8c4555ccc5 ("scripts: add `generate_rust_analyzer.py`")
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250210-rust-analyzer-bindings-include-v2-1-23dff845edc3@gmail.com
[ Slightly reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The macros crate has depended on std and proc_macro since its
introduction in commit 1fbde52bde ("rust: add `macros` crate"). These
dependencies were omitted from commit 8c4555ccc5 ("scripts: add
`generate_rust_analyzer.py`") resulting in missing go-to-definition and
autocomplete, and false-positive warnings emitted from rust-analyzer
such as:
[{
"resource": "/Users/tamird/src/linux/rust/macros/module.rs",
"owner": "_generated_diagnostic_collection_name_#1",
"code": {
"value": "non_snake_case",
"target": {
"$mid": 1,
"path": "/rustc/",
"scheme": "https",
"authority": "doc.rust-lang.org",
"query": "search=non_snake_case"
}
},
"severity": 4,
"message": "Variable `None` should have snake_case name, e.g. `none`",
"source": "rust-analyzer",
"startLineNumber": 123,
"startColumn": 17,
"endLineNumber": 123,
"endColumn": 21
}]
Add the missing dependencies to improve the developer experience.
[ Fiona had a different approach (thanks!) at:
https://lore.kernel.org/rust-for-linux/20241205115438.234221-1-me@kloenk.dev/
But Tamir and Fiona agreed to this one. - Miguel ]
Fixes: 8c4555ccc5 ("scripts: add `generate_rust_analyzer.py`")
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Diagnosed-by: Chayim Refael Friedman <chayimfr@gmail.com>
Link: https://github.com/rust-lang/rust-analyzer/issues/17759#issuecomment-2646328275
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250210-rust-analyzer-macros-core-dep-v3-1-45eb4836f218@gmail.com
[ Removed `return`. Changed tag name. Added Link. Slightly
reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add a "template" crc-clmul-template.h that can generate RISC-V Zbc
optimized CRC functions. Each generated CRC function is parameterized
by CRC length and bit order, and it accepts a pointer to the constants
struct required for the specific CRC polynomial desired. Update
gen-crc-consts.py to support generating the needed constants structs.
This makes it possible to easily wire up a Zbc optimized implementation
of almost any CRC.
The design generally follows what I did for x86, but it is simplified by
using RISC-V's scalar carryless multiplication Zbc, which has no
equivalent on x86. RISC-V's clmulr instruction is also helpful. A
potential switch to Zvbc (or support for Zvbc alongside Zbc) is left for
future work. For long messages Zvbc should be fastest, but it would
need to be shown to be worthwhile over just using Zbc which is
significantly more convenient to use, especially in the kernel context.
Compared to the existing Zbc-optimized CRC32 code and the earlier
proposed Zbc-optimized CRC-T10DIF code
(https://lore.kernel.org/r/20250211071101.181652-1-zhihang.shao.iscas@gmail.com),
this submission deduplicates the code among CRC variants and is
significantly more optimized. It uses "folding" to take better
advantage of instruction-level parallelism (to a more limited extent
than x86 for now, but it could be extended to more), it reworks the
Barrett reduction to eliminate unnecessary instructions, and it
documents all the math used and makes all the constants reproducible.
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250216225530.306980-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Improve two error messages in the script by mentioning the doctest file
path from which the doctest was generated from.
This will allow, in case the conversion fails, to get directly the file
name triggering the issue, making the bug fixing process faster.
Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com>
Link: https://lore.kernel.org/r/20250228170530.950268-2-guillaume1.gomez@gmail.com
[ Reworded and removed an unneeded added parameter comma. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Limit integer wrap-around mitigation to only the "size_t" type (for
now). Notably this covers all special functions/builtins that return
"size_t", like sizeof(). This remains an experimental feature and is
likely to be replaced with type annotations.
Reviewed-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20250307041914.937329-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
To make integer wrap-around mitigation actually useful, the associated
sanitizers must not instrument cases where the wrap-around is explicitly
defined (e.g. "-2UL"), being tested for (e.g. "if (a + b < a)"), or
where it has no impact on code flow (e.g. "while (var--)"). Enable
pattern exclusions for the integer wrap sanitizers.
Reviewed-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20250307041914.937329-2-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Since we're going to approach integer overflow mitigation a type at a
time, we need to enable all of the associated sanitizers, and then opt
into types one at a time.
Rename the existing "signed wrap" sanitizer to just the entire topic area:
"integer wrap". Enable the implicit integer truncation sanitizers, with
required callbacks and tests.
Notably, this requires features (currently) only available in Clang,
so we can depend on the cc-option tests to determine availability
instead of doing version tests.
Link: https://lore.kernel.org/r/20250307041914.937329-1-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Subshell evaluations are not exempt from errexit, so if a command is
not available, `which` will fail and exit the script as a whole.
This causes the helpful error messages to not be printed if they are
tacked on using a `$?` comparison.
Resolve the issue by using chains of logical operators, which are not
subject to the effects of errexit.
Fixes: e37c1877ba ("scripts/selinux: modernize mdp")
Signed-off-by: Tim Schumacher <tim.schumacher1@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Since commit 5f73e7d038 ("kbuild: refactor cross-compiling
linux-headers package"), the linux-headers pacman package fails
to build when "O=" is set. The build system complains:
/mnt/chroot/linux/scripts/Makefile.build:41: mnt/chroots/linux-mainline/pacman/linux-upstream/pkg/linux-upstream-headers/usr//lib/modules/6.14.0-rc3-00350-g771dba31fffc/build/scripts/Makefile: No such file or directory
This is because the "srcroot" variable is set to "." and the
"build" variable is set to the absolute path. This makes the
"src" variables point to wrong directory.
Change the "build" variable to a relative path to "." to
fix build.
Fixes: 5f73e7d038 ("kbuild: refactor cross-compiling linux-headers package")
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The UM builds distinguish i386 from x86_64 via SUBARCH, but we don't
support building i386 directly with Clang. To make SUBARCH work for
i386 UM, we need to explicitly test for it.
This lets me run i386 KUnit tests with Clang:
$ ./tools/testing/kunit/kunit.py run \
--make_options LLVM=1 \
--make_options SUBARCH=i386
...
Fixes: c7500c1b53 ("um: Allow builds with Clang")
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250304162124.it.785-kees@kernel.org
Tested-by: David Gow <davidgow@google.com>
Signed-off-by: Kees Cook <kees@kernel.org>
ARM 64 uses -fpatchable-function-entry=4,2 which adds padding before the
function and the addresses in the mcount_loc point there instead of the
function entry that is returned by nm. In order to find a function from nm
to make sure it's not an unused weak function, the entries in the
mcount_loc section needs to match the entries from nm. Since it can be an
instruction before the entry, add a before_func variable that ARM 64 can
set to 8, and if the mcount_loc entry is within 8 bytes of the nm function
entry, then it will be considered a match.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: "Arnd Bergmann" <arnd@arndb.de>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/20250225182054.815536219@goodmis.org
Fixes: ef378c3b82 ("scripts/sorttable: Zero out weak functions in mcount_loc table")
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In a similar vein as to this pending commit in the x86/asm tree:
a3e8fe814a ("x86/build: Raise the minimum GCC version to 8.1")
... bump the minimum supported version of LLVM for building x86 kernels
to 15.0.0, as that is the first version that has support for
'-mstack-protector-guard-symbol', which is used unconditionally after:
80d47defdd ("x86/stackprotector/64: Convert to normal per-CPU variable"):
Older Clang versions will fail the build with:
clang-14: error: unknown argument: '-mstack-protector-guard-symbol=__ref_stack_chk_guard'
Fixes: 80d47defdd ("x86/stackprotector/64: Convert to normal per-CPU variable")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Brian Gerst <brgerst@gmail.com>
Link: https://lore.kernel.org/r/20250220-x86-bump-min-llvm-for-stackp-v1-1-ecb3c906e790@kernel.org
When a function is annotated as "weak" and is overridden, the code is not
removed. If it is traced, the fentry/mcount location in the weak function
will be referenced by the "__mcount_loc" section. This will then be added
to the available_filter_functions list. Since only the address of the
functions are listed, to find the name to show, a search of kallsyms is
used.
Since kallsyms will return the function by simply finding the function
that the address is after but before the next function, an address of a
weak function will show up as the function before it. This is because
kallsyms does not save names of weak functions. This has caused issues in
the past, as now the traced weak function will be listed in
available_filter_functions with the name of the function before it.
At best, this will cause the previous function's name to be listed twice.
At worse, if the previous function was marked notrace, it will now show up
as a function that can be traced. Note that it only shows up that it can
be traced but will not be if enabled, which causes confusion.
https://lore.kernel.org/all/20220412094923.0abe90955e5db486b7bca279@kernel.org/
The commit b39181f7c6 ("ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid
adding weak function") was a workaround to this by checking the function
address before printing its name. If the address was too far from the
function given by the name then instead of printing the name it would
print: __ftrace_invalid_address___<invalid-offset>
The real issue is that these invalid addresses are listed in the ftrace
table look up which available_filter_functions is derived from. A place
holder must be listed in that file because set_ftrace_filter may take a
series of indexes into that file instead of names to be able to do O(1)
lookups to enable filtering (many tools use this method).
Even if kallsyms saved the size of the function, it does not remove the
need of having these place holders. The real solution is to not add a weak
function into the ftrace table in the first place.
To solve this, the sorttable.c code that sorts the mcount regions during
the build is modified to take a "nm -S vmlinux" input, sort it, and any
function listed in the mcount_loc section that is not within a boundary of
the function list given by nm is considered a weak function and is zeroed
out.
Note, this does not mean they will remain zero when booting as KASLR
will still shift those addresses. To handle this, the entries in the
mcount_loc section will be ignored if they are zero or match the
kaslr_offset() value.
Before:
~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l
551
After:
~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l
0
Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250218200022.883095980@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
