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2025-10-15perf print-events: Remove print_symbol_eventsIan Rogers
Now legacy hardware events are in json there's no need for a specific printing routine that previously served for both hardware and software events. The associated event_symbols_hw is also removed. To support the previous filtered version use an event glob of "legacy hardware" which matches the topic of the json events. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf print-events: Remove print_hwcache_eventsIan Rogers
Now legacy cache events are in json there's no need for a specific printing routine. To support the previous filtered version use an event glob of "legacy cache" which matches the topic of the json events. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf jevents: Add legacy-hardware and legacy-cache jsonIan Rogers
The legacy-hardware.json is added containing hardware events similarly to the software.json file. A difference is that for the software PMU the name is known and matches sysfs. In the legacy-hardware.json no Unit/PMU is specified for the events meaning default_core is used and the events will appear for all core PMUs. There are potentially 1216 legacy cache events, rather than list them in a json file add a make_legacy_cache.py helper to generate them. By using json for legacy hardware and cache events: descriptions of the events can be added; events can be marked as deprecated, such as those misleadingly named l2 (deprecated is also used to mark all events that weren't previously displayed in perf list); and the name lookup becomes case insensitive. The C string encoding all the perf events and metrics is increased in size by 123,499 bytes which will increase the perf binary size. Later changes will remove hard coded event parsing for legacy hardware and cache events, turning parsing overhead into a binary search during event lookup. That event descriptions are based off of those in perf_event_open man page, credit to Vince Weaver <vincent.weaver@maine.edu>. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf pmu: Add and use legacy_terms in alias informationIan Rogers
Add support to finding/adding events from the default_core event table. If an event already exists from sysfs/json then the default_core configuration is saved in the legacy_terms string. Lazily use the legacy_terms string to set a legacy hardware or cache event as deprecated if the core PMU doesn't support it. Use the legacy terms string to set the alternate_hw_config, avoiding the value needing to be passed from the parse_events parser. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf jevents: Add legacy json terms and default_core event table helperIan Rogers
Add json LegacyConfigCode and LegacyCacheCode values that translate to legacy-hardware-config and legacy-cache-config event terms respectively. Add perf_pmu__default_core_events_table as a means to find a default_core event table that will later contain legacy events. In situations like hypervisors it is more likely that tables will be NULL. Rather than testing in the calling PMU code, early exit in the pmu-event.c routines. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf parse-events: Add terms for legacy hardware and cache config valuesIan Rogers
Add the PMU terms legacy-hardware-config and legacy-cache-config. These terms are similar to the config term in that their values are assigned to the perf_event_attr config value. They differ in that the PMU type is switched to be either PERF_TYPE_HARDWARE or PERF_TYPE_HW_CACHE, and the PMU type is moved into the extended type information of the config value. This will allow later patches to add legacy events to json. An example use of the terms is in the following: ``` $ perf stat -vv -e 'cpu/legacy-hardware-config=1/,cpu/legacy-cache-config=0x10001/' true Using CPUID GenuineIntel-6-8D-1 Attempt to add: cpu/legacy-hardware-config=0x1/ ..after resolving event: cpu/legacy-hardware-config=0x1/ Attempt to add: cpu/legacy-cache-config=0x10001/ ..after resolving event: cpu/legacy-cache-config=0x10001/ Control descriptor is not initialized ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) size 136 config 0x1 (PERF_COUNT_HW_INSTRUCTIONS) sample_type IDENTIFIER read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING disabled 1 inherit 1 enable_on_exec 1 ------------------------------------------------------------ sys_perf_event_open: pid 994937 cpu -1 group_fd -1 flags 0x8 = 3 ------------------------------------------------------------ perf_event_attr: type 3 (PERF_TYPE_HW_CACHE) size 136 config 0x10001 (PERF_COUNT_HW_CACHE_RESULT_MISS | PERF_COUNT_HW_CACHE_OP_READ | PERF_COUNT_HW_CACHE_L1I) sample_type IDENTIFIER read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING disabled 1 inherit 1 enable_on_exec 1 ------------------------------------------------------------ sys_perf_event_open: pid 994937 cpu -1 group_fd -1 flags 0x8 = 4 cpu/legacy-hardware-config=1/: -1: 1364046 414756 414756 cpu/legacy-cache-config=0x10001/: -1: 57453 414756 414756 cpu/legacy-hardware-config=1/: 1364046 414756 414756 cpu/legacy-cache-config=0x10001/: 57453 414756 414756 Performance counter stats for 'true': 1,364,046 cpu/legacy-hardware-config=1/ 57,453 cpu/legacy-cache-config=0x10001/ 0.001988593 seconds time elapsed 0.002194000 seconds user 0.000000000 seconds sys ``` Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf pmu: Factor term parsing into a perf_event_attr into a helperIan Rogers
Factor existing functionality in perf_pmu__name_from_config into a helper that will be used in later patches. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf pmu: Use fd rather than FILE from new_aliasIan Rogers
The FILE argument was necessary for the scanner but now that functionality is not being used we can switch to just using io__getline which should cut down on stdio buffer usage. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf parse-events: Remove unused FILE input argument to scannerIan Rogers
Now the events file isn't directly parsed from a FILE but stored in a string prior to parsing, remove the FILE argument to the associated scanner functions as they only ever pass NULL. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf pmu: Don't eagerly parse event termsIan Rogers
When an event/alias is created for a PMU the terms are eagerly parsed using parse_events_terms. For a command like perf stat or perf record, the particular event/alias will be found, the terms parsed, the terms cloned for use in the event parsing, and then the terms used to configure the perf_event_attr. Events/aliases may be eagerly loaded, such as from sysfs or in perf list, in which case the aliases terms will be little or never used. To avoid redundant work, to avoid cloning, and to reduce memory overhead, hold the terms for an event as a string until they need handling as a term list. This may introduce duplicate parsing if an event is repeated in a list, but this situation is expected to be uncommon. Measuring the number of instructions before and after with a sysfs event and perf stat, there is a minor reduction in the number of instructions executed by 0.3%. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf jevents: Support copying the source json files to OUTPUTIan Rogers
The jevents command expects all json files to be organized under a single directory. When generating json files from scripts (to reduce laborious copy and paste in the json) we don't want to generate the json into the source directory if there is an OUTPUT directory specified. This change adds a GEN_JSON for this case where the GEN_JSON copies the JSON files to OUTPUT, only when OUTPUT is specified. The Makefile.perf clean code is updated to clean up this directory when present. This patch is part of: https://lore.kernel.org/lkml/20240926173554.404411-12-irogers@google.com/ which was similarly adding support for generating json in scripts for the consumption of jevents.py. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf record: Skip don't fail for events that don't openIan Rogers
Whilst for many tools it is an expected behavior that failure to open a perf event is a failure, ARM decided to name PMU events the same as legacy events and then failed to rename such events on a server uncore SLC PMU. As perf's default behavior when no PMU is specified is to open the event on all PMUs that advertise/"have" the event, this yielded failures when trying to make the priority of legacy and sysfs/json events uniform - something requested by RISC-V and ARM. A legacy event user on ARM hardware may find their event opened on an uncore PMU which for perf record will fail. Arnaldo suggested skipping such events which this patch implements. Rather than have the skipping conditional on running on ARM, the skipping is done on all architectures as such a fundamental behavioral difference could lead to problems with tools built/depending on perf. An example of perf record failing to open events on x86 is: ``` $ perf record -e data_read,cycles,LLC-prefetch-read -a sleep 0.1 Error: Failure to open event 'data_read' on PMU 'uncore_imc_free_running_0' which will be removed. The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (data_read). "dmesg | grep -i perf" may provide additional information. Error: Failure to open event 'data_read' on PMU 'uncore_imc_free_running_1' which will be removed. The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (data_read). "dmesg | grep -i perf" may provide additional information. Error: Failure to open event 'LLC-prefetch-read' on PMU 'cpu' which will be removed. The LLC-prefetch-read event is not supported. [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 2.188 MB perf.data (87 samples) ] $ perf report --stats Aggregated stats: TOTAL events: 17255 MMAP events: 284 ( 1.6%) COMM events: 1961 (11.4%) EXIT events: 1 ( 0.0%) FORK events: 1960 (11.4%) SAMPLE events: 87 ( 0.5%) MMAP2 events: 12836 (74.4%) KSYMBOL events: 83 ( 0.5%) BPF_EVENT events: 36 ( 0.2%) FINISHED_ROUND events: 2 ( 0.0%) ID_INDEX events: 1 ( 0.0%) THREAD_MAP events: 1 ( 0.0%) CPU_MAP events: 1 ( 0.0%) TIME_CONV events: 1 ( 0.0%) FINISHED_INIT events: 1 ( 0.0%) cycles stats: SAMPLE events: 87 ``` If all events fail to open then the perf record will fail: ``` $ perf record -e LLC-prefetch-read true Error: Failure to open event 'LLC-prefetch-read' on PMU 'cpu' which will be removed. The LLC-prefetch-read event is not supported. Error: Failure to open any events for recording ``` As an evlist may have dummy events that open when all command line events fail we ignore dummy events when detecting if at least some events open. This still permits the dummy event on its own to be used as a permission check: ``` $ perf record -e dummy true [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.046 MB perf.data ] ``` but allows failure when a dummy event is implicilty inserted or when there are insufficient permissions to open it: ``` $ perf record -e LLC-prefetch-read -a true Error: Failure to open event 'LLC-prefetch-read' on PMU 'cpu' which will be removed. The LLC-prefetch-read event is not supported. Error: Failure to open any events for recording ``` As the first parsed event in an evlist is marked as tracking, removing this event can remove tracking from the evlist, removing mmap events and breaking symbolization. To avoid this, if a tracking event is removed then the next event has tracking added. The issue with legacy events is that on RISC-V they want the driver to not have mappings from legacy to non-legacy config encodings for each vendor/model due to size, complexity and difficulty to update. It was reported that on ARM Apple-M? CPUs the legacy mapping in the driver was broken and the sysfs/json events should always take precedent, however, it isn't clear this is still the case. It is the case that without working around this issue a legacy event like cycles without a PMU can encode differently than when specified with a PMU - the non-PMU version favoring legacy encodings, the PMU one avoiding legacy encodings. Legacy events are also case sensitive while sysfs/json events are not. The patch removes events and then adjusts the idx value for each evsel. This is done so that the dense xyarrays used for file descriptors, etc. don't contain broken entries. On ARM it could be common following this change to see a lot of warnings for the cycles event due to many ARM PMUs advertising the cycles event (ARM inconsistently have events bus_cycles and then cycles implying CPU cycles, they also sometimes have a cpu_cycles event). As cycles is a popular event, avoid potentially spamming users with error messages on ARM when there are multiple cycles events in the evlist, the error is still shown when verbose is enabled. Prior versions without adding the tracking data and not warning for cycles on ARM was: Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: James Clark <james.clark@linaro.org> Tested-by: Leo Yan <leo.yan@arm.com> Tested-by: Atish Patra <atishp@rivosinc.com> Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf stat: Avoid wildcarding PMUs for default eventsIan Rogers
Without a PMU perf matches an event against any PMU with the event. Unfortunately some PMU drivers advertise a "cycles" event which is typically just a core event. To make perf's behavior consistent, just look up default events with their designated PMU types. Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf perf_api_probe: Avoid scanning all PMUs, try software PMU firstIan Rogers
Scan the software PMU first rather than last as it is the least likely to fail the probe. Specifying the software PMU by name was enabled by commit 9957d8c801fe ("perf jevents: Add common software event json"). For hardware events, add core PMU names when getting events to probe so that not all PMUs are scanned. For example, when legacy events support wildcards and for the event "cycles:u" on x86, we want to only scan the "cpu" PMU and not all uncore PMUs for the event too. Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15perf parse-events: Fix legacy cache events if event is duplicated in a PMUIan Rogers
The term list when adding an event to a PMU is expected to have the event name for the alias lookup. Also, set found_supported so that -EINVAL isn't returned. Fixes: 62593394f66a ("perf parse-events: Legacy cache names on all PMUs and lower priority") Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-15selftests: livepatch: use canonical ftrace pathFushuai Wang
Since v4.1 kernel, a new interface for ftrace called "tracefs" was introduced, which is usually mounted in /sys/kernel/tracing. Therefore, tracing files can now be accessed via either the legacy path /sys/kernel/debug/tracing or the newer path /sys/kernel/tracing. Signed-off-by: Fushuai Wang <wangfushuai@baidu.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-10-14selftests/bpf: make arg_parsing.c more robust to crashesAndrii Nakryiko
We started getting a crash in BPF CI, which seems to originate from test_parse_test_list_file() test and is happening at this line: ASSERT_OK(strcmp("test_with_spaces", set.tests[0].name), "test 0 name"); One way we can crash there is if set.cnt zero, which is checked for with ASSERT_EQ() above, but we proceed after this regardless of the outcome. Instead of crashing, we should bail out with test failure early. Similarly, if parse_test_list_file() fails, we shouldn't be even looking at set, so bail even earlier if ASSERT_OK() fails. Fixes: 64276f01dce8 ("selftests/bpf: Test_progs can read test lists from file") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Ihor Solodrai <ihor.solodrai@linux.dev> Link: https://lore.kernel.org/r/20251014202037.72922-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-10-14livepatch/klp-build: Introduce klp-build script for generating livepatch modulesJosh Poimboeuf
Add a klp-build script which automates the generation of a livepatch module from a source .patch file by performing the following steps: - Builds an original kernel with -function-sections and -fdata-sections, plus objtool function checksumming. - Applies the .patch file and rebuilds the kernel using the same options. - Runs 'objtool klp diff' to detect changed functions and generate intermediate binary diff objects. - Builds a kernel module which links the diff objects with some livepatch module init code (scripts/livepatch/init.c). - Finalizes the livepatch module (aka work around linker wreckage) using 'objtool klp post-link'. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add base objtool support for livepatch modulesJosh Poimboeuf
In preparation for klp-build, enable "classic" objtool to work on livepatch modules: - Avoid duplicate symbol/section warnings for prefix symbols and the .static_call_sites and __mcount_loc sections which may have already been extracted by klp diff. - Add __klp_funcs to the IBT function pointer section whitelist. - Prevent KLP symbols from getting incorrectly classified as cold subfunctions. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Refactor prefix symbol creation codeJosh Poimboeuf
The prefix symbol creation code currently ignores all errors, presumably because some functions don't have the leading NOPs. Shuffle the code around a bit, improve the error handling and document why some errors are ignored. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool/klp: Add post-link subcommand to finalize livepatch modulesJosh Poimboeuf
Livepatch needs some ELF magic which linkers don't like: - Two relocation sections (.rela*, .klp.rela*) for the same text section. - Use of SHN_LIVEPATCH to mark livepatch symbols. Unfortunately linkers tend to mangle such things. To work around that, klp diff generates a linker-compliant intermediate binary which encodes the relevant KLP section/reloc/symbol metadata. After module linking, the .ko then needs to be converted to an actual livepatch module. Introduce a new klp post-link subcommand to do so. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool/klp: Add --debug option to show cloning decisionsJosh Poimboeuf
Add a --debug option to klp diff which prints cloning decisions and an indented dependency tree for all cloned symbols and relocations. This helps visualize which symbols and relocations were included and why. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool/klp: Introduce klp diff subcommand for diffing object filesJosh Poimboeuf
Add a new klp diff subcommand which performs a binary diff between two object files and extracts changed functions into a new object which can then be linked into a livepatch module. This builds on concepts from the longstanding out-of-tree kpatch [1] project which began in 2012 and has been used for many years to generate livepatch modules for production kernels. However, this is a complete rewrite which incorporates hard-earned lessons from 12+ years of maintaining kpatch. Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script (coming in a later patch) which injects #line directives into the source .patch to preserve the original line numbers at compile time. Note the end result of this subcommand is not yet functionally complete. Livepatch needs some ELF magic which linkers don't like: - Two relocation sections (.rela*, .klp.rela*) for the same text section. - Use of SHN_LIVEPATCH to mark livepatch symbols. Unfortunately linkers tend to mangle such things. To work around that, klp diff generates a linker-compliant intermediate binary which encodes the relevant KLP section/reloc/symbol metadata. After module linking, a klp post-link step (coming soon) will clean up the mess and convert the linked .ko into a fully compliant livepatch module. Note this subcommand requires the diffed binaries to have been compiled with -ffunction-sections and -fdata-sections, and processed with 'objtool --checksum'. Those constraints will be handled by a klp-build script introduced in a later patch. Without '-ffunction-sections -fdata-sections', reliable object diffing would be infeasible due to toolchain limitations: - For intra-file+intra-section references, the compiler might occasionally generated hard-coded instruction offsets instead of relocations. - Section-symbol-based references can be ambiguous: - Overlapping or zero-length symbols create ambiguity as to which symbol is being referenced. - A reference to the end of a symbol (e.g., checking array bounds) can be misinterpreted as a reference to the next symbol, or vice versa. A potential future alternative to '-ffunction-sections -fdata-sections' would be to introduce a toolchain option that forces symbol-based (non-section) relocations. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool/klp: Add --debug-checksum=<funcs> to show per-instruction checksumsJosh Poimboeuf
Add a --debug-checksum=<funcs> option to the check subcommand to print the calculated checksum of each instruction in the given functions. This is useful for determining where two versions of a function begin to diverge. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool/klp: Add --checksum option to generate per-function checksumsJosh Poimboeuf
In preparation for the objtool klp diff subcommand, add a command-line option to generate a unique checksum for each function. This will enable detection of functions which have changed between two versions of an object file. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add ANNOTATE_DATA_SPECIALJosh Poimboeuf
In preparation for the objtool klp diff subcommand, add an ANNOTATE_DATA_SPECIAL macro which annotates special section entries so that objtool can determine their size and location and extract them when needed. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add annotype() helperJosh Poimboeuf
... for reading annotation types. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add elf_create_file()Josh Poimboeuf
Add interface to enable the creation of a new ELF file. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add elf_create_reloc() and elf_init_reloc()Josh Poimboeuf
elf_create_rela_section() is quite limited in that it requires the caller to know how many relocations need to be allocated up front. In preparation for the objtool klp diff subcommand, allow an arbitrary number of relocations to be created and initialized on demand after section creation. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add elf_create_data()Josh Poimboeuf
In preparation for the objtool klp diff subcommand, refactor elf_add_string() by adding a new elf_add_data() helper which allows the adding of arbitrary data to a section. Make both interfaces global so they can be used by the upcoming klp diff code. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Generalize elf_create_section()Josh Poimboeuf
In preparation for the objtool klp diff subcommand, broaden the elf_create_section() interface to give callers more control and reduce duplication of some subtle setup logic. While at it, make elf_create_rela_section() global so sections can be created by the upcoming klp diff code. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Generalize elf_create_symbol()Josh Poimboeuf
In preparation for the objtool klp diff subcommand, broaden the elf_create_symbol() interface to give callers more control and reduce duplication of some subtle setup logic. While at it, make elf_create_symbol() and elf_create_section_symbol() global so sections can be created by the upcoming klp diff code. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Simplify special symbol handling in elf_update_symbol()Josh Poimboeuf
!sym->sec isn't actually a thing: even STT_UNDEF and other special symbol types belong to NULL section 0. Simplify the initialization of 'shndx' accordingly. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Refactor add_jump_destinations()Josh Poimboeuf
The add_jump_destinations() logic is a bit weird and convoluted after being incrementally tweaked over the years. Refactor it to hopefully be more logical and straightforward. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Reindent check_options[]Josh Poimboeuf
Bring the cmdline check_options[] array back into vertical alignment for better readability. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Resurrect --backup optionJosh Poimboeuf
The --backup option was removed with the following commit: aa8b3e64fd39 ("objtool: Create backup on error and print args") ... which tied the backup functionality to --verbose, and only for warnings/errors. It's a bit inelegant and out of scope to tie that to --verbose. Bring back the old --backup option, but with the new behavior: only on warnings/errors, and print the args to make it easier to recreate. Suggested-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Rename --Werror to --werrorJosh Poimboeuf
The objtool --Werror option name is stylistically inconsistent: halfway between GCC's single-dash capitalized -Werror and objtool's double-dash --lowercase convention, making it unnecessarily hard to remember. Make the 'W' lower case (--werror) for consistency with objtool's other options. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Avoid emptying lists for duplicate sectionsJosh Poimboeuf
When a to-be-created section already exists, there's no point in emptying the various lists if their respective sections already exist. In fact it's better to leave them intact as they might get used later. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Simplify reloc offset calculation in unwind_read_hints()Josh Poimboeuf
Simplify the relocation offset calculation in unwind_read_hints(), similar to other conversions which have already been done. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Mark prefix functionsJosh Poimboeuf
In preparation for the objtool klp diff subcommand, introduce a flag to identify __pfx_*() and __cfi_*() functions in advance so they don't need to be manually identified every time a check is needed. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Fix weak symbol hole detection for .cold functionsJosh Poimboeuf
When ignore_unreachable_insn() looks for weak function holes which jump to their .cold functions, it assumes the parent function comes before the corresponding .cold function in the symbol table. That's not necessarily the case with -ffunction-sections. Mark all the holes beforehand (including .cold functions) so the ordering of the discovery doesn't matter. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Mark .cold subfunctionsJosh Poimboeuf
Introduce a flag to identify .cold subfunctions so they can be detected easier and faster. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Add section/symbol type helpersJosh Poimboeuf
Add some helper macros to improve readability. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Convert elf iterator macros to use 'struct elf'Josh Poimboeuf
'struct objtool_file' is specific to the check code and doesn't belong in the elf code which is supposed to be objtool_file-agnostic. Convert the elf iterator macros to use 'struct elf' instead. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Remove .parainstructions referenceJosh Poimboeuf
The .parainstructions section no longer exists since the following commit: 60bc276b129e ("x86/paravirt: Switch mixed paravirt/alternative calls to alternatives"). Remove the reference to it. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Clean up compiler flag usageJosh Poimboeuf
KBUILD_HOSTCFLAGS and KBUILD_HOSTLDFLAGS aren't defined when objtool is built standalone. Also, the EXTRA_WARNINGS flags are rather arbitrary. Make things simpler and more consistent by specifying compiler flags explicitly and tweaking the warnings. Also make a few code tweaks to make the new warnings happy. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Const string cleanupJosh Poimboeuf
Use 'const char *' where applicable. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Check for missing annotation entries in read_annotate()Josh Poimboeuf
Add a sanity check to make sure none of the relocations for the .discard.annotate_insn section have gone missing. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Fix "unexpected end of section" warning for alternativesJosh Poimboeuf
Due to the short circuiting logic in next_insn_to_validate(), control flow may silently transition from .altinstr_replacement to .text without a corresponding nested call to validate_branch(). As a result the validate_branch() 'sec' variable doesn't get reinitialized, which can trigger a confusing "unexpected end of section" warning which blames .altinstr_replacement rather than the offending fallthrough function. Fix that by not caching the section. There's no point in doing that anyway. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14objtool: Fix __pa_symbol() relocation handlingJosh Poimboeuf
__pa_symbol() generates a relocation which refers to a physical address. Convert it to back its virtual form before calculating the addend. Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>