perf c2c:
- Add 'function view' in perf c2c report TUI (switched by pressing 'TAB'
in the cacheline view) to organize samples around functions rather than
cachelines in 3-level hierarchy:
Level 1: Read-side function (sorted by estimated Cycles %)
Level 2: Contending writer functions (sorted by Store count)
Level 3: Shared cacheline addresses
Users can navigate the entries and fold/unfold using 'e' key. An example
output would look like below:
Shared Data Functions Table (19 entries, sorted on Cycles %)
Cycles Store
% count Function / Contending function / Cacheline
----------------------------------------------------------------------
+ 35.67% 876 + [k] cpupri_set
+ 24.31% 424 + [k] pull_rt_task
- 16.53% 555 - [k] dequeue_pushable_task
145 - [k] pull_rt_task
145 0xff2d0082809da080
139 - [k] enqueue_pushable_task
70 0xff2d00a2071f9640
69 0xff2d0082809da000
python module support:
- Extend "perf" python module so that it can be fully functional. The goal
is to run scripts directly, not by 'perf script' command. This would give
better performance as well as more control to build standalone programs
with UI.
- Add LiveSession helper (perf_live.py) to enable live event collection
directly from Python using perf.evlist and perf.parse_events.
perf stat:
- Add --hide-zero-events option to suppress zero-count events.
- Reject conflicting --field-separator and --json-output options.
- Fix duplicate event output with --for-each-cgroup.
perf sched latency:
- Add -H/--histogram and --hist-mode (log|linear) options to show scheduler
wait latency histograms.
- Add --time option to filter analysis by time span in 'perf sched latency'.
ARM CoreSight:
- Synthesize callchains for instruction samples from CoreSight trace
using thread stack ('--itrace=g...').
- Support call indentation ('perf script -F +callindent') to display call
depth hierarchy on branch samples.
- Decode ETE (Embedded Trace Extension) exception packets.
Build system:
- Add 'make install-build-deps' target to install required packages.
- Parallelize JSON and metric pre-computation in jevents.py for faster builds.
Vendor event/metric updates:
- Add Intel Nova Lake events and update tables for existing models.
- Update AMD Zen 5 and Zen 6 core events.
- Update Arm64 Tegra410 metrics and PowerPC hcalls.
Internal changes and fixes:
- Harden trace-event and synthetic event parsing against corrupted data.
- Fix unwinding of multi-threaded processes in libdw unwinder.
- Fix memory leaks in various commands and python bindings.
- Speed up 'perf test' shell tests.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Merge tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Namhyung Kim:
"perf c2c:
- Add 'function view' in perf c2c report TUI (switched by pressing
'TAB' in the cacheline view) to organize samples around functions
rather than cachelines in 3-level hierarchy:
Level 1: Read-side function (sorted by estimated Cycles %)
Level 2: Contending writer functions (sorted by Store count)
Level 3: Shared cacheline addresses
Users can navigate the entries and fold/unfold using 'e' key. An
example output would look like below:
Shared Data Functions Table (19 entries, sorted on Cycles %)
Cycles Store
% count Function / Contending function / Cacheline
----------------------------------------------------------------------
+ 35.67% 876 + [k] cpupri_set
+ 24.31% 424 + [k] pull_rt_task
- 16.53% 555 - [k] dequeue_pushable_task
145 - [k] pull_rt_task
145 0xff2d0082809da080
139 - [k] enqueue_pushable_task
70 0xff2d00a2071f9640
69 0xff2d0082809da000
python module support:
- Extend "perf" python module so that it can be fully functional. The
goal is to run scripts directly, not by 'perf script' command. This
would give better performance as well as more control to build
standalone programs with UI.
- Add LiveSession helper (perf_live.py) to enable live event
collection directly from Python using perf.evlist and
perf.parse_events.
perf stat:
- Add --hide-zero-events option to suppress zero-count events
- Reject conflicting --field-separator and --json-output options
- Fix duplicate event output with --for-each-cgroup
perf sched latency:
- Add -H/--histogram and --hist-mode (log|linear) options to show
scheduler wait latency histograms
- Add --time option to filter analysis by time span in 'perf sched
latency'
ARM CoreSight:
- Synthesize callchains for instruction samples from CoreSight trace
using thread stack ('--itrace=g...')
- Support call indentation ('perf script -F +callindent') to display
call depth hierarchy on branch samples
- Decode ETE (Embedded Trace Extension) exception packets
Build system:
- Add 'make install-build-deps' target to install required packages
- Parallelize JSON and metric pre-computation in jevents.py for
faster builds
Vendor event/metric updates:
- Add Intel Nova Lake events and update tables for existing models
- Update AMD Zen 5 and Zen 6 core events
- Update Arm64 Tegra410 metrics and PowerPC hcalls
Internal changes and fixes:
- Harden trace-event and synthetic event parsing against corrupted
data
- Fix unwinding of multi-threaded processes in libdw unwinder
- Fix memory leaks in various commands and python bindings
- Speed up 'perf test' shell tests"
* tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (232 commits)
perf vendor events arm64: Fix Tegra410 Olympus event 0x0197
perf vendor events arm64: fix swapped MetricGroup for Tegra410 L1 prefetcher metrics
perf evlist: Warn when 'sleep' workload is used without system-wide (-a) option
perf c2c: document function view in perf-c2c man page
perf c2c: add function view browser UI and cacheline detail
perf c2c: build and finalize the function view hierarchy
perf c2c: add function view hierarchy entry creation
perf c2c: add function view stats merge and memory management
perf c2c: add HPP list parsing for function view columns
perf c2c: add column rendering for function view
perf c2c: add function view model skeleton
perf c2c: extract shared data structures into util/c2c.h
perf test sample-parsing: Validate PERF_FORMAT_GROUP values without LOST
perf dso: Replace assert with runtime check in dso__read_symbol()
perf dso: Guard against cache underflow on short reads in dso_cache__memcpy()
perf dso: Use stored fd error instead of stale errno in file_read() and file_size()
perf dso: Guard close() against invalid fd in dso__decompress_kmodule_path()
perf dso: Guard against errno==0 when dso__get_filename() returns NULL
perf build: install-build-deps: add RHEL family devel package mapping
perf build: Remove leftover feature tests for removed cxx and clang support
...
map_dump() closes the map fd in its error path, and do_dump() then
closes the same fd again after a successful dump. Closing an already
closed fd leaves errno set to EBADF, which poisons later errno checks
such as the batch file read check in do_batch(). Let do_dump() own the
fd and remove the close from map_dump().
The same double-close pattern exists in do_show_subset(): both
show_map_close_json() and show_map_close_plain() already close the fd,
so drop the extra close() there as well.
Also propagate the error when bpf_map_get_info_by_fd() fails on a
subsequent map in do_dump(): set err = -1 before breaking out of the
loop, so a later failure is not silently hidden after an earlier
iteration succeeded.
Fixes: 99f9863a0c ("bpftool: Match maps by name")
Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260810142224.2907373-2-chenyuan_fl@163.com
Enhance bpftool to generate skeletons that properly handle global percpu
variables. The generated skeleton now includes a dedicated structure for
percpu data, allowing users to initialize and access percpu variables more
efficiently.
For global percpu variables, the skeleton now includes a nested
structure, e.g.:
struct test_global_percpu_data {
struct bpf_object_skeleton *skeleton;
struct bpf_object *obj;
struct {
struct bpf_map *percpu;
} maps;
// ...
struct test_global_percpu_data__percpu {
int data;
char run;
struct {
char set;
int i;
int nums[7];
} struct_data;
int nums[7];
} *percpu;
// ...
};
* The "struct test_global_percpu_data__percpu *percpu" points to
initialized data, which is actually "maps.percpu->mmaped".
* Before loading the skeleton, updating the
"struct test_global_percpu_data__percpu *percpu" modifies the initial
value of the corresponding global percpu variables.
* After loading the skeleton, "maps.percpu->mmaped" has been marked as
read-only in libbpf. If users want to update the global percpu
variables, they have to update the "maps.percpu" map instead.
* For lightweight skeleton, "lskel->percpu" will be protected by
"mprotect(p, sz, PROT_READ)".
* For subskeleton, those variables of global percpu data will be
skipped.
Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-7-leon.hwang@linux.dev
Kfunc declarations can identify arena arguments through parameter name
suffixes without repeating KF_ARENA_ARG flags in their BTF ID sets.
resolve_btfids currently misses those arguments when synthesizing the
address_space(1) attributes used by generated vmlinux.h files.
Teach the arena prototype rewrite to recognize __arena and
__arena__nullable directly on each parameter. Keep KF_ARENA_ARG1 and
KF_ARENA_ARG2 handling for explicitly flagged kfuncs, while allowing
suffixes on any argument without synthesizing kfunc flags.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://patch.msgid.link/20260812193842.2879226-2-memxor@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
At the moment there are more callsites that want bpf_verbose_insn() to
not print a newline after the instruction, than callsites that want a
newline. Drop '\n' from disasm.c. Non-functional change.
The changes in bpftool are verified by writing a bpf program using a
variety of instructions and comparing `prog dump xlated` output in the
following modes: plain, opcodes, visual, visual opcodes. The output
before and after the changes is identical.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20260807-static-zext-v4-1-b6c270013c77@gmail.com
resolve_btfids now emits the bpf_kfunc and bpf_fastcall BTF decl tags and
the arena address_space(1) type attribute for kfuncs, which were
previously produced by pahole.
Reflect this in the in-tree comments and documentation.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://patch.msgid.link/20260807032029.78092-7-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Emit the bpf_kfunc decl tag for every discovered kfunc, and bpf_fastcall
for kfuncs flagged KF_FASTCALL. These were previously produced by pahole
under --btf_features=decl_tag_kfuncs.
resolve_btfids now discovers kfuncs from the BTF ID sets [1] and
becomes the source of truth for their annotations.
Drop decl_tag_kfuncs pahole feature flag from scripts/Makefile.btf
[1] https://lore.kernel.org/all/20260722233518.778854-1-ihor.solodrai@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/20260807032029.78092-5-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
For kfuncs flagged with KF_ARENA_RET, KF_ARENA_ARG1 or KF_ARENA_ARG2,
the address_space(1) attribute (a type tag with kflag=1) must be
emitted for the corresponding type in BTF. This was previously done by
pahole via the "attributes" BTF feature [1].
Implement the emission of the arena attributes in resolve_btfids: for
flagged kfuncs create a new function prototype with updated BTF types.
The original proto may be shared with sibling FUNCs, so it is not
modified in place.
Emission is unconditional: kbuild controls the pahole flags, so the
input BTF is expected to not have these attributes. Invalid
declarations are reported as errors.
Drop the "attributes" pahole feature from scripts/Makefile.btf
resolve_btfids now emits them for all supported pahole versions.
[1] https://lore.kernel.org/dwarves/20250228194654.1022535-1-ihor.solodrai@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://patch.msgid.link/20260807032029.78092-3-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
btf2btf() adds new types to the BTF: the KF_IMPLICIT_ARGS transform
synthesizes an _impl FUNC together with its FUNC_PROTO and copies of the
kfunc's decl tags. Nothing deduplicates them afterwards. pahole runs
btf__dedup() on its own output, but that happens before resolve_btfids
sees the BTF, so any type the tool itself creates is emitted as-is, even
when a structurally identical type is already present.
Call btf__dedup() at the start of finalize_btf(), so that base
distillation and the by-name sort both operate on the canonical set of
types.
On an x86_64 build with the BPF selftests config this removes 17
duplicate FUNC_PROTOs from vmlinux BTF.
The dedup call increases runtime of resolve_btfids on vmlinux by 30-40%.
The performance hit is an acceptable cost to keep kernel BTF deduped [1].
[1] https://lore.kernel.org/bpf/986e6f4e-4b51-4440-a37c-9624906d7370@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://patch.msgid.link/20260807032029.78092-2-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
A kfunc may be listed in several BTF ID sets, which is expected
because different kfuncs are available to BPF programs depending on
their type.
However kfunc flags across different BTF ID sets must be consistent [1].
The flags should be considered a part of the kfunc declaration,
because they influence its BTF representation and verifier handling.
Enforce the kfunc flag consistency in resolve_btifds by hard failing
on error and blocking kernel (or module) build.
[1] https://lore.kernel.org/bpf/9b2196dd-443b-4632-ae11-030cdbdc59b4@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260722233518.778854-9-ihor.solodrai@linux.dev
collect_kfuncs() currently uses bpf_kfunc decl tags to identify the
list of kfuncs. The decl tags are generated by pahole, which makes
current implementation implicitly rely on those tags being generated.
The authoritative source, used by the the BPF verifier for kfunc
registration, of functions being BPF kfuncs are
BTF_KFUNCS_START()/END() declarations. These are BTF_ID_SET8 under the
hood. Currently resolve_btfids reads kfunc flags from these sets, and
populates them with BTF IDs.
Implement kfunc discovery from BTF_ID_SET8 symbols in resolve_btfids,
removing the dependency on pahole's emmission of decl tags.
Walk BTF_ID_KIND_SET8 sets, and use the address-to-symbol index to
look up set entry's BTF_ID symbol name (before .BTF_ids is patched),
recording the paired flags directly. This makes find_kfunc_flags()
helper unnecessary, so it's removed.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260722233518.778854-8-ihor.solodrai@linux.dev
process_kfunc_with_implicit_args() skips generating <name>_impl
function when one already exists for backwards compatibility.
It uses btf__find_by_name_kind(), which searches the base BTF before
the split BTF. When resolve_btfids processes a module, a same-named
_impl in vmlinux would be found and the module's own counterpart would
not be created.
Fix by using btf__find_by_name_kind_own() for the lookup.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260722233518.778854-6-ihor.solodrai@linux.dev
Keep an address-sorted index of parsed .BTF_ids symbols so that the
original BTF_ID symbol name can be recovered from an entry address.
Use the index in find_kfunc_flags() to scan BTF_SET8_KFUNCS entries
directly and match each entry back to the requested kfunc.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260722233518.778854-3-ihor.solodrai@linux.dev
push_*() helpers in resolve_btfids contain copy-pasted array growth
logic. Factor it out into ensure_mem() - a simplified variant of
libbpf_ensure_mem(), and use it in the helpers.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260722233518.778854-2-ihor.solodrai@linux.dev
Try to remove some, but not all duplicate toolchain definitions. In
these instances, their makefiles already include
tools/scripts/Makefile.include which defines these in a consistent way.
STRIP is the only one that was set with an '=', but I don't think it
was significant so that difference can be dropped.
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Looking up a prog or map by name walks the whole id space. There is a
window between bpf_prog_get_next_id()/bpf_map_get_next_id() and getting
an fd for that id in which an unrelated object can be freed, and the
lookup then fails with ENOENT and aborts the whole command.
Skip such ids and keep walking, the same way do_show() already does.
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://lore.kernel.org/bpf/20260720071520.396363-1-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
bpftool_prog_sign() signed only the loader instructions. The metadata
blob the loader installs was left to an in-loader hash check, which
the kernel now performs at load time over insns || metadata.
Sign that same concatenation: pass the metadata blob (gen_loader_opts
data) through to bpftool_prog_sign() and feed insns || metadata to
CMS_final(). The excl_prog_hash stays a digest of the instructions
alone; it binds the metadata map to the loader and is matched against
prog->digest by the verifier, independent of what the signature covers.
The signed artifact is now plain data: both bytes the signature
covers are embedded verbatim in the generated skeleton, so signing
and verifying an lskel is an ordinary CMS operation that a signer or
auditor can perform (or reproduce) offline, without analyzing loader
bytecode to establish what the signature actually attests to.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260708075343.358712-6-daniel@iogearbox.net
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
bpftool_prog_sign() ignores the return value of EVP_Digest(). If the
digest computation fails (context allocation failure, or a digest
fetch failure under OpenSSL), EVP_Digest() returns 0 and leaves the
output buffer untouched, but the function still reports success.
Fixes: 40863f4d6e ("bpftool: Add support for signing BPF programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260708075343.358712-5-daniel@iogearbox.net
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Currently each build with resolve_btfids enabled unnecessarily prints
the line 'INSTALL libsubcmd_headers' from libsubcmd.
Use the libcmd headers from source tree instead, without installation.
The same was done for objtool in commit ac99992677 ("objtool: Include
libsubcmd headers directly from source tree"), albeit for a different
reason.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Tested-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://patch.msgid.link/20260702-libsubcmd-spam-v1-1-300ec142a62f@linutronix.de
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
The btf_vlen(), btf_kind() and btf_kflag() inline helpers defined in
tools/lib/bpf/btf.h are thin wrappers around the BTF_INFO_VLEN(),
BTF_INFO_KIND() and BTF_INFO_KFLAG() UAPI macros - each one simply
returns the corresponding macro applied to t->info.
bpftool already uses these helpers in most places, but 13 call sites
in btf.c and btf_dumper.c still open-code the raw macros. Use the
helpers consistently, matching the rest of bpftool as well as libbpf.
No functional change.
Signed-off-by: Liang Luo <luoliang@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260702012311.2265001-1-luoliang@kylinos.cn
struct_ops frees the global btf_vmlinux object.
In batch mode, a later struct_ops command can reuse stale state.
Reset the BTF pointer and cached map info state.
Fixes: 65c9362859 ("bpftool: Add struct_ops support")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/9F9017160ABE125F+20260624025055.1574875-3-chenyichong@uniontech.com
get_map_kv_btf() caches the vmlinux BTF object when a map uses
btf_vmlinux_value_type_id. map dump released that object when the
command completed, but left the global pointer stale.
The same cached object can also be returned to print_key_value(), which
freed it directly. That leaves btf_vmlinux dangling before the command
cleanup path runs.
Use free_map_kv_btf() for per-entry cleanup, and reset the cached
btf_vmlinux pointer when the map command releases the object. This keeps
batch mode from reusing a freed BTF object.
Fixes: 4e1ea33292 ("bpftool: Support dumping a map with btf_vmlinux_value_type_id")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/9072F43B3F74DF91+20260624025055.1574875-2-chenyichong@uniontech.com
Commit 9080b97689 ("bpftool: Pass host flags to bootstrap libbpf")
started building the bootstrap libbpf with HOST_CFLAGS, stripping the
warning options that are unsuitable for that build by filtering out
-W -Wall -Wextra -Wformat -Wformat-signedness.
HOST_CFLAGS inherits EXTRA_WARNINGS, which includes -Wformat-security
and -Wformat-y2k. The filter drops -Wall and -Wformat (the latter being
what actually enables -Wformat), but leaves those two -Wformat-* children
in LIBBPF_BOOTSTRAP_CFLAGS. Building the bootstrap libbpf with it then
warns:
cc1: warning: '-Wformat-y2k' ignored without '-Wformat'
cc1: warning: '-Wformat-security' ignored without '-Wformat'
The warning is easy to miss in an in-tree build: tools/lib/bpf/Makefile
re-adds -Wall via "override CFLAGS += -Wall", which re-enables -Wformat
for the libbpf objects, so only libbpf's feature-detection probe (which
uses the passed CFLAGS verbatim) leaks the two warnings. The standalone
libbpf Makefile (github.com/libbpf/libbpf, used by the bpftool mirror)
instead uses "CFLAGS ?= ... -Wall", which the passed-in CFLAGS overrides,
so -Wall is never re-added and every bootstrap object warns.
Use a -Wformat% wildcard in the filter-out so the orphaned children are
removed together with the parent.
Fixes: 9080b97689 ("bpftool: Pass host flags to bootstrap libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260630205418.3483969-1-andrii@kernel.org
bpftool cgroup show and tree call libbpf_find_kernel_btf() to
resolve attach_btf names, but never release the returned BTF object.
For cgroup tree, do_show_tree_fn() is called once for each cgroup
visited by nftw(). When more than one cgroup has attached programs,
each callback overwrites btf_vmlinux with a new object and loses the
previous allocation.
Load vmlinux BTF only once during a tree walk and release it when
cgroup show or tree completes. Reset btf_vmlinux_id at the same time
so batch mode starts with clean state.
Fixes: 596f5fb2ea ("bpftool: implement cgroup tree for BPF_LSM_CGROUP")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/24357C69B4405079+20260617090117.280222-1-chenyichong@uniontech.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Prepare for future changes where EXTRA_CFLAGS may include flags not
applicable to the host compiler.
Move the HOST_CFLAGS assignment before appending EXTRA_CFLAGS to
CFLAGS so that HOST_CFLAGS does not inherit flags from EXTRA_CFLAGS.
Acked-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-2-c76e5250ea1c@arm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpftool builds a bootstrap libbpf with HOSTCC, but the libbpf submake can
still inherit target build flags through CFLAGS. This can break cross
builds when host objects are compiled with target-only options.
Since HOST_CFLAGS contains warning options that are not suitable for
building libbpf, use LIBBPF_BOOTSTRAP_CFLAGS with the warning options
removed to build the bootstrap libbpf. Clear EXTRA_CFLAGS so target
extra flags are not mixed into the host bootstrap libbpf build.
Signed-off-by: Leo Yan <leo.yan@arm.com>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-1-c76e5250ea1c@arm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When the perf build executes 'make -C ../bpf/bpftool bootstrap', bpftool's
Makefile unconditionally evaluated feature checks for llvm, libcap, libbfd,
and disassembler libraries because the bootstrap target was not exempted.
Since the bootstrap bpftool strictly compiles minimal AST parsing and C
code generation logic without linking LLVM or disassembler libraries, these
feature check sub-makes are completely redundant.
Exempt the bootstrap target from non-essential feature tests to eliminate
unneeded sub-make fork overhead during Kbuild startup.
Tested-by: James Clark <james.clark@linaro.org>
Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20260531010750.525160-1-irogers@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_prog_query() returns a negative errno on failure.
query_flow_dissector() currently closes the namespace fd and then reads
errno to decide whether -EINVAL means that the running kernel does not
support flow dissector queries.
That errno check controls behavior, not just diagnostics: -EINVAL is
handled as a non-fatal old-kernel case, while any other error makes bpftool
net fail.
The namespace fd is opened read-only, so close() is not expected to
commonly fail in normal use. Still, the BPF_PROG_QUERY error is already
available in err, and reading errno after an intervening close() is
fragile. If close() does change errno, the compatibility branch may be
based on close()'s error instead of the BPF_PROG_QUERY result.
This was reproduced with an LD_PRELOAD fault injector that forced
BPF_PROG_QUERY for BPF_FLOW_DISSECTOR to fail with EINVAL and then
forced close() on the netns fd to fail with EIO. The unpatched bpftool
reported "can't query prog: Input/output error". With this change, the
same injected failure is handled as the intended non-fatal EINVAL
compatibility case.
Use the libbpf-returned error code instead. Keep the existing errno reset
in the non-fatal path to preserve batch mode behavior. The success path
is unchanged.
Fixes: 7f0c57fec8 ("bpftool: show flow_dissector attachment status")
Signed-off-by: Woojin Ji <random6.xyz@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Leon Hwang <leon.hwang@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260603003339.33791-1-random6.xyz@gmail.com
Assisted-by: ChatGPT:gpt-5.5
When generating light skeletons for BPF programs containing struct_ops
maps, bpftool incorrectly outputs a stray literal 't' instead of a tab
character for the map file descriptor member in the links structure.
This causes a compilation error when the generated light skeleton is
used.
Correct the format string by replacing 't' with '\t'.
Fixes: 08ac454e25 ("libbpf: Auto-attach struct_ops BPF maps in BPF skeleton")
Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260520-struct_ops_gen_typo_fix-v1-1-4dee3771da46@google.com
Add the fsession attach type to the usage of bpftool in do_help().
Meanwhile, add it to the bash-completion and bpftool-prog.rst too.
Acked-by: Leon Hwang <leon.hwang@linux.dev>
Acked-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20260412060346.142007-4-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The following kfuncs currently accept void *meta__ign argument:
* bpf_obj_new_impl
* bpf_obj_drop_impl
* bpf_percpu_obj_new_impl
* bpf_percpu_obj_drop_impl
* bpf_refcount_acquire_impl
* bpf_list_push_back_impl
* bpf_list_push_front_impl
* bpf_rbtree_add_impl
The __ign suffix is an indicator for the verifier to skip the argument
in check_kfunc_args(). Then, in fixup_kfunc_call() the verifier may
set the value of this argument to struct btf_struct_meta *
kptr_struct_meta from insn_aux_data.
BPF programs must pass a dummy NULL value when calling these kfuncs.
Additionally, the list and rbtree _impl kfuncs also accept an implicit
u64 argument, which doesn't require __ign suffix because it's a
scalar, and BPF programs explicitly pass 0.
Add new kfuncs with KF_IMPLICIT_ARGS [1], that correspond to each
_impl kfunc accepting meta__ign. The existing _impl kfuncs remain
unchanged for backwards compatibility.
To support this, add "btf_struct_meta" to the list of recognized
implicit argument types in resolve_btfids.
Implement is_kfunc_arg_implicit() in the verifier, that determines
implicit args by inspecting both a non-_impl BTF prototype of the
kfunc.
Update the special_kfunc_list in the verifier and relevant checks to
support both the old _impl and the new KF_IMPLICIT_ARGS variants of
btf_struct_meta users.
[1] https://lore.kernel.org/bpf/20260120222638.3976562-1-ihor.solodrai@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20260327203241.3365046-1-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Introduce SKIP_LLVM, SKIP_LIBBFD, and SKIP_CRYPTO build flags that let
users build bpftool without these optional dependencies.
SKIP_LLVM=1 skips LLVM even when detected. SKIP_LIBBFD=1 prevents the
libbfd JIT disassembly fallback when LLVM is absent. Together, they
produce a bpftool with no disassembly support.
SKIP_CRYPTO=1 excludes sign.c and removes the -lcrypto link dependency.
Inline stubs in main.h return errors with a clear message if signing
functions are called at runtime.
Use BPFTOOL_WITHOUT_CRYPTO (not HAVE_LIBCRYPTO_SUPPORT) as the C
define, following the BPFTOOL_WITHOUT_SKELETONS naming convention for
bpftool-internal build config, leaving HAVE_LIBCRYPTO_SUPPORT free for
proper feature detection in the future.
All three flags are propagated through the selftests Makefile to bpftool
sub-builds.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260312-b4-bpftool_build-v2-1-4c9d57133644@meta.com
The "|| echo -lzstd" default makes zstd an unconditional link
dependency of resolve_btfids. On systems where libzstd-dev is not
installed and pkg-config fails, the linker fails:
ld: cannot find -lzstd: No such file or directory
libzstd is a transitive dependency of libelf, so the -lzstd flag is
strictly necessary only for static builds [1].
Remove ZSTD_LIBS variable, and instead set LIBELF_LIBS depending on
whether the build is static or not. Use $(HOSTPKG_CONFIG) as primary
source of the flags list.
Also add a default value for HOSTPKG_CONFIG in case it's not built via
the toplevel Makefile. Pass it from selftests/bpf too.
[1] https://lore.kernel.org/bpf/4ff82800-2daa-4b9f-95a9-6f512859ee70@linux.dev/
Reported-by: BPF CI Bot (Claude Opus 4.6) <bot+bpf-ci@kernel.org>
Reported-by: Vitaly Chikunov <vt@altlinux.org>
Closes: https://lore.kernel.org/bpf/aaWqMcK-2AQw5dx8@altlinux.org/
Fixes: 4021848a90 ("selftests/bpf: Pass through build flags to bpftool and resolve_btfids")
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Reviewed-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/20260305014730.3123382-1-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add support for specifying multiple file sources in 'bpftool btf dump'
to generate a single C header containing types from vmlinux plus
multiple kernel modules:
bpftool btf dump file /sys/kernel/btf/mod1 file /sys/kernel/btf/mod2 format c
This is useful for BPF programs that need to access types defined in
kernel modules. Previously this required a separate bpftool invocation
for each module, producing separate headers that could not be combined
due to overlapping vmlinux type definitions.
The implementation collects all file paths, then for the multi-file
case creates an empty split BTF on the vmlinux base and iteratively
merges each module's types into it via btf__add_btf(). The single-file
code path is preserved exactly to avoid any regression risk.
Auto-detection of vmlinux as the base BTF from sysfs paths works as
before. If vmlinux itself appears in the file list it is skipped with
a warning since its types are already provided by the base.
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/b19c2760ffe48cec546dd3810d237f8cad20d606.1772657690.git.josef@toxicpanda.com
Running resolve_btfids with ASAN reveals memory leaks in btf_id
handling.
- Change get_id() to use a local buffer
- Make btf_id__add() strdup the name internally
- Add btf_id__free_all() that frees all nodese of a tree
- Call the cleanup function on exit for every tree
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260223190736.649171-8-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
EXTRA_* and SAN_* build flags were not correctly propagated to bpftool
and resolve_btids when building selftests/bpf. This led to various
build errors on attempt to build with SAN_CFLAGS="-fsanitize=address",
for example.
Fix the makefiles to address this:
- Pass SAN_CFLAGS/SAN_LDFLAGS to bpftool and resolve_btfids build
- Propagate EXTRA_LDFLAGS to resolve_btfids link command
- Use pkg-config to detect zlib and zstd for resolve_btfids, similar
libelf handling
Also check for ASAN flag in selftests/bpf/Makefile for convenience.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260223190736.649171-7-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Netlink requires that the recv buffer used during dumps is at least
min(PAGE_SIZE, 8k) (see the man page). Otherwise the messages will
get truncated. Make sure bpftool follows this requirement, avoid
missing information on systems with large pages.
Acked-by: Quentin Monnet <qmo@kernel.org>
Fixes: 7084566a23 ("tools/bpftool: Remove libbpf_internal.h usage in bpftool")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20260217194150.734701-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Preserve original relative order of anonymous or same-named
types to improve the consistency.
No functional changes.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260202120114.3707141-1-dolinux.peng@gmail.com
When building selftests/bpf with EXTRA_LDFLAGS=-static the follwoing
error happens:
LINK /ws/linux/tools/testing/selftests/bpf/tools/build/bpftool/bootstrap/bpftool
/usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-dso_dlfcn.o): in function `dlfcn_globallookup':
[...]
/usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-c_zlib.o): in function `zlib_oneshot_expand_block':
(.text+0xc64): undefined reference to `uncompress'
/usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-c_zlib.o): in function `zlib_oneshot_compress_block':
(.text+0xce4): undefined reference to `compress'
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:252: /ws/linux/tools/testing/selftests/bpf/tools/build/bpftool/bootstrap/bpftool] Error 1
make: *** [Makefile:327: /ws/linux/tools/testing/selftests/bpf/tools/sbin/bpftool] Error 2
make: *** Waiting for unfinished jobs....
This is caused by wrong order of dependencies in the Makefile. Fix it.
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260128211255.376933-1-ihor.solodrai@linux.dev
Implement BTF modifications in resolve_btfids to support BPF kernel
functions with implicit arguments.
For a kfunc marked with KF_IMPLICIT_ARGS flag, a new function
prototype is added to BTF that does not have implicit arguments. The
kfunc's prototype is then updated to a new one in BTF. This prototype
is the intended interface for the BPF programs.
A <func_name>_impl function is added to BTF to make the original kfunc
prototype searchable for the BPF verifier. If a <func_name>_impl
function already exists in BTF, its interpreted as a legacy case, and
this step is skipped.
Whether an argument is implicit is determined by its type:
currently only `struct bpf_prog_aux *` is supported.
As a result, the BTF associated with kfunc is changed from
__bpf_kfunc bpf_foo(int arg1, struct bpf_prog_aux *aux);
into
bpf_foo_impl(int arg1, struct bpf_prog_aux *aux);
__bpf_kfunc bpf_foo(int arg1);
For more context see previous discussions and patches [1][2].
[1] https://lore.kernel.org/dwarves/ba1650aa-fafd-49a8-bea4-bdddee7c38c9@linux.dev/
[2] https://lore.kernel.org/bpf/20251029190113.3323406-1-ihor.solodrai@linux.dev/
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260120222638.3976562-6-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since recently [1][2] resolve_btfids executes final adjustments to the
kernel/module BTF before it's embedded into the target binary.
To keep the implementation simple, a clear and stable "pipeline" of
how BTF data flows through resolve_btfids would be helpful. Some BTF
modifications may change the ids of the types, so it is important to
maintain correct order of operations with respect to .BTF_ids
resolution too.
This patch refactors the BTF handling to establish the following
sequence:
- load target ELF sections
- load .BTF_ids symbols
- this will be a dependency of btf2btf transformations in
subsequent patches
- load BTF and its base as is
- (*) btf2btf transformations will happen here
- finalize_btf(), introduced in this patch
- does distill base and sort BTF
- resolve and patch .BTF_ids
This approach helps to avoid fixups in .BTF_ids data in case the ids
change at any point of BTF processing, because symbol resolution
happens on the finalized, ready to dump, BTF data.
This also gives flexibility in BTF transformations, because they will
happen on BTF that is not distilled and/or sorted yet, allowing to
freely add, remove and modify BTF types.
[1] https://lore.kernel.org/bpf/20251219181321.1283664-1-ihor.solodrai@linux.dev/
[2] https://lore.kernel.org/bpf/20260109130003.3313716-1-dolinux.peng@gmail.com/
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260120222638.3976562-5-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
