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6 daysresolve_btfids: Fix linker flags detectionIhor Solodrai-2/+7
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: 4021848a903e ("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>
2026-02-24resolve_btfids: Fix memory leaks reported by ASANIhor Solodrai-27/+54
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>
2026-02-24selftests/bpf: Pass through build flags to bpftool and resolve_btfidsIhor Solodrai-2/+5
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>
2026-02-04resolve_btfids: Refactor the sort_btf_by_name functionDonglin Peng-7/+11
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
2026-01-20resolve_btfids: Support for KF_IMPLICIT_ARGSIhor Solodrai-0/+382
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>
2026-01-20resolve_btfids: Introduce finalize_btf() stepIhor Solodrai-21/+48
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>
2026-01-13tools/resolve_btfids: Support BTF sorting featureDonglin Peng-0/+64
This introduces a new BTF sorting phase that specifically sorts BTF types by name in ascending order, so that the binary search can be used to look up types. Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260109130003.3313716-4-dolinux.peng@gmail.com
2025-12-31resolve_btfids: Implement --patch_btfidsIhor Solodrai-0/+117
Recent changes in BTF generation [1] rely on ${OBJCOPY} command to update .BTF_ids section data in target ELF files. This exposed a bug in llvm-objcopy --update-section code path, that may lead to corruption of a target ELF file. Specifically, because of the bug st_shndx of some symbols may be (incorrectly) set to 0xffff (SHN_XINDEX) [2][3]. While there is a pending fix for LLVM, it'll take some time before it lands (likely in 22.x). And the kernel build must keep working with older LLVM toolchains in the foreseeable future. Using GNU objcopy for .BTF_ids update would work, but it would require changes to LLVM-based build process, likely breaking existing build environments as discussed in [2]. To work around llvm-objcopy bug, implement --patch_btfids code path in resolve_btfids as a drop-in replacement for: ${OBJCOPY} --update-section .BTF_ids=${btf_ids} ${elf} Which works specifically for .BTF_ids section: ${RESOLVE_BTFIDS} --patch_btfids ${btf_ids} ${elf} This feature in resolve_btfids can be removed at some point in the future, when llvm-objcopy with a relevant bugfix becomes common. [1] https://lore.kernel.org/bpf/20251219181321.1283664-1-ihor.solodrai@linux.dev/ [2] https://lore.kernel.org/bpf/20251224005752.201911-1-ihor.solodrai@linux.dev/ [3] https://github.com/llvm/llvm-project/issues/168060#issuecomment-3533552952 Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Link: https://lore.kernel.org/r/20251231012558.1699758-1-ihor.solodrai@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-19resolve_btfids: Change in-place update with raw binary outputIhor Solodrai-81/+143
Currently resolve_btfids updates .BTF_ids section of an ELF file in-place, based on the contents of provided BTF, usually within the same input file, and optionally a BTF base. Change resolve_btfids behavior to enable BTF transformations as part of its main operation. To achieve this, in-place ELF write in resolve_btfids is replaced with generation of the following binaries: * ${1}.BTF with .BTF section data * ${1}.BTF_ids with .BTF_ids section data if it existed in ${1} * ${1}.BTF.base with .BTF.base section data for out-of-tree modules The execution of resolve_btfids and consumption of its output is orchestrated by scripts/gen-btf.sh introduced in this patch. The motivation for emitting binary data is that it allows simplifying resolve_btfids implementation by delegating ELF update to the $OBJCOPY tool [1], which is already widely used across the codebase. There are two distinct paths for BTF generation and resolve_btfids application in the kernel build: for vmlinux and for kernel modules. For the vmlinux binary a .BTF section is added in a roundabout way to ensure correct linking. The patch doesn't change this approach, only the implementation is a little different. Before this patch it worked as follows: * pahole consumed .tmp_vmlinux1 [2] and added .BTF section with llvm-objcopy [3] to it * then everything except the .BTF section was stripped from .tmp_vmlinux1 into a .tmp_vmlinux1.bpf.o object [2], later linked into vmlinux * resolve_btfids was executed later on vmlinux.unstripped [4], updating it in-place After this patch gen-btf.sh implements the following: * pahole consumes .tmp_vmlinux1 and produces a *detached* file with raw BTF data * resolve_btfids consumes .tmp_vmlinux1 and detached BTF to produce (potentially modified) .BTF, and .BTF_ids sections data * a .tmp_vmlinux1.bpf.o object is then produced with objcopy copying BTF output of resolve_btfids * .BTF_ids data gets embedded into vmlinux.unstripped in link-vmlinux.sh by objcopy --update-section For kernel modules, creating a special .bpf.o file is not necessary, and so embedding of sections data produced by resolve_btfids is straightforward with objcopy. With this patch an ELF file becomes effectively read-only within resolve_btfids, which allows deleting elf_update() call and satellite code (like compressed_section_fix [5]). Endianness handling of .BTF_ids data is also changed. Previously the "flags" part of the section was bswapped in sets_patch() [6], and then Elf_Type was modified before elf_update() to signal to libelf that bswap may be necessary. With this patch we explicitly bswap entire data buffer on load and on dump. [1] https://lore.kernel.org/bpf/131b4190-9c49-4f79-a99d-c00fac97fa44@linux.dev/ [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/link-vmlinux.sh?h=v6.18#n110 [3] https://git.kernel.org/pub/scm/devel/pahole/pahole.git/tree/btf_encoder.c?h=v1.31#n1803 [4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/link-vmlinux.sh?h=v6.18#n284 [5] https://lore.kernel.org/bpf/20200819092342.259004-1-jolsa@kernel.org/ [6] https://lore.kernel.org/bpf/cover.1707223196.git.vmalik@redhat.com/ Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20251219181825.1289460-3-ihor.solodrai@linux.dev
2025-12-19resolve_btfids: Always build with -Wall -WerrorIhor Solodrai-1/+2
resolve_btfids builds without compiler warnings currently, so let's enforce this for future changes with '-Wall -Werror' flags [1]. [1] https://lore.kernel.org/bpf/1957a60b-6c45-42a7-b525-a6e335a735ff@linux.dev/ Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/20251219181321.1283664-5-ihor.solodrai@linux.dev
2025-12-19resolve_btfids: Introduce enum btf_id_kindIhor Solodrai-23/+60
Instead of using multiple flags, make struct btf_id tagged with an enum value indicating its kind in the context of resolve_btfids. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20251219181321.1283664-4-ihor.solodrai@linux.dev
2025-12-19resolve_btfids: Factor out load_btf()Ihor Solodrai-13/+34
Increase the lifetime of parsed BTF in resolve_btfids by factoring load_btf() routine out of symbols_resolve() and storing the base_btf and btf pointers in the struct object. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20251219181321.1283664-3-ihor.solodrai@linux.dev
2025-12-19resolve_btfids: Rename object btf field to btf_pathIhor Solodrai-5/+5
Rename the member of `struct object` holding the path to BTF data if provided via --btf arg. `btf_path` is less ambiguous. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20251219181321.1283664-2-ihor.solodrai@linux.dev
2025-06-10tools/resolve_btfids: Fix build when cross compiling kernel with clang.Suleiman Souhlal-1/+1
When cross compiling the kernel with clang, we need to override CLANG_CROSS_FLAGS when preparing the step libraries. Prior to commit d1d096312176 ("tools: fix annoying "mkdir -p ..." logs when building tools in parallel"), MAKEFLAGS would have been set to a value that wouldn't set a value for CLANG_CROSS_FLAGS, hiding the fact that we weren't properly overriding it. Fixes: 56a2df7615fa ("tools/resolve_btfids: Compile resolve_btfids as host program") Signed-off-by: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20250606074538.1608546-1-suleiman@google.com
2025-02-25Merge tag 'perf-tools-fixes-for-v6.14-2-2025-02-25' of ↵Linus Torvalds-2/+0
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools fixes from Arnaldo Carvalho de Melo: - Fix tools/ quiet build Makefile infrastructure that was broken when working on tools/perf/ without testing on other tools/ living utilities. * tag 'perf-tools-fixes-for-v6.14-2-2025-02-25' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: tools: Remove redundant quiet setup tools: Unify top-level quiet infrastructure
2025-02-18tools: Remove redundant quiet setupCharlie Jenkins-2/+0
Q is exported from Makefile.include so it is not necessary to manually set it. Reviewed-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Benjamin Tissoires <bentiss@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Lukasz Luba <lukasz.luba@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Mykola Lysenko <mykolal@fb.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Zhang Rui <rui.zhang@intel.com> Link: https://lore.kernel.org/r/20250213-quiet_tools-v3-2-07de4482a581@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-12-10tools/resolve_btfids: Add --fatal_warnings optionThomas Weißschuh-2/+10
Currently warnings emitted by resolve_btfids are buried in the build log and are slipping into mainline frequently. Add an option to elevate warnings to hard errors so the CI bots can catch any new warnings. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20241204-resolve_btfids-v3-1-e6a279a74cfd@weissschuh.net
2024-10-23resolve_btfids: Fix compiler warningsEder Zulian-2/+2
Initialize 'set' and 'set8' pointers to NULL in sets_patch to prevent possible compiler warnings which are issued for various optimization levels, but do not happen when compiling with current default compilation options. For example, when compiling resolve_btfids with $ make "HOSTCFLAGS=-O2 -Wall" -C tools/bpf/resolve_btfids/ clean all Clang version 17.0.6 and GCC 13.3.1 issue following -Wmaybe-uninitialized warnings for variables 'set8' and 'set': In function ‘sets_patch’, inlined from ‘symbols_patch’ at main.c:748:6, inlined from ‘main’ at main.c:823:6: main.c:163:9: warning: ‘set8’ may be used uninitialized [-Wmaybe-uninitialized] 163 | eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:729:17: note: in expansion of macro ‘pr_debug’ 729 | pr_debug("sorting addr %5lu: cnt %6d [%s]\n", | ^~~~~~~~ main.c: In function ‘main’: main.c:682:37: note: ‘set8’ was declared here 682 | struct btf_id_set8 *set8; | ^~~~ In function ‘sets_patch’, inlined from ‘symbols_patch’ at main.c:748:6, inlined from ‘main’ at main.c:823:6: main.c:163:9: warning: ‘set’ may be used uninitialized [-Wmaybe-uninitialized] 163 | eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:729:17: note: in expansion of macro ‘pr_debug’ 729 | pr_debug("sorting addr %5lu: cnt %6d [%s]\n", | ^~~~~~~~ main.c: In function ‘main’: main.c:683:36: note: ‘set’ was declared here 683 | struct btf_id_set *set; | ^~~ Signed-off-by: Eder Zulian <ezulian@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20241022172329.3871958-2-ezulian@redhat.com
2024-07-22tools/resolve_btfids: Fix comparison of distinct pointer types warning in ↵Liwei Song-1/+1
resolve_btfids Add a type cast for set8->pairs to fix below compile warning: main.c: In function 'sets_patch': main.c:699:50: warning: comparison of distinct pointer types lacks a cast 699 | BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id); | ^~ Fixes: 9707ac4fe2f5 ("tools/resolve_btfids: Refactor set sorting with types from btf_ids.h") Signed-off-by: Liwei Song <liwei.song.lsong@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240722083305.4009723-1-liwei.song.lsong@gmail.com
2024-06-17resolve_btfids: Handle presence of .BTF.base sectionAlan Maguire-0/+8
Now that btf_parse_elf() handles .BTF.base section presence, we need to ensure that resolve_btfids uses .BTF.base when present rather than the vmlinux base BTF passed in via the -B option. Detect .BTF.base section presence and unset the base BTF path to ensure that BTF ELF parsing will do the right thing. Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240613095014.357981-7-alan.maguire@oracle.com
2024-05-24bpf: Fix potential integer overflow in resolve_btfidsFriedrich Vock-1/+1
err is a 32-bit integer, but elf_update returns an off_t, which is 64-bit at least on 64-bit platforms. If symbols_patch is called on a binary between 2-4GB in size, the result will be negative when cast to a 32-bit integer, which the code assumes means an error occurred. This can wrongly trigger build failures when building very large kernel images. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Signed-off-by: Friedrich Vock <friedrich.vock@gmx.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240514070931.199694-1-friedrich.vock@gmx.de
2024-02-07tools/resolve_btfids: Fix cross-compilation to non-host endiannessViktor Malik-0/+35
The .BTF_ids section is pre-filled with zeroed BTF ID entries during the build and afterwards patched by resolve_btfids with correct values. Since resolve_btfids always writes in host-native endianness, it relies on libelf to do the translation when the target ELF is cross-compiled to a different endianness (this was introduced in commit 61e8aeda9398 ("bpf: Fix libelf endian handling in resolv_btfids")). Unfortunately, the translation will corrupt the flags fields of SET8 entries because these were written during vmlinux compilation and are in the correct endianness already. This will lead to numerous selftests failures such as: $ sudo ./test_verifier 502 502 #502/p sleepable fentry accept FAIL Failed to load prog 'Invalid argument'! bpf_fentry_test1 is not sleepable verification time 34 usec stack depth 0 processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 Summary: 0 PASSED, 0 SKIPPED, 1 FAILED Since it's not possible to instruct libelf to translate just certain values, let's manually bswap the flags (both global and entry flags) in resolve_btfids when needed, so that libelf then translates everything correctly. Fixes: ef2c6f370a63 ("tools/resolve_btfids: Add support for 8-byte BTF sets") Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/7b6bff690919555574ce0f13d2a5996cacf7bf69.1707223196.git.vmalik@redhat.com
2024-02-07tools/resolve_btfids: Refactor set sorting with types from btf_ids.hViktor Malik-14/+21
Instead of using magic offsets to access BTF ID set data, leverage types from btf_ids.h (btf_id_set and btf_id_set8) which define the actual layout of the data. Thanks to this change, set sorting should also continue working if the layout changes. This requires to sync the definition of 'struct btf_id_set8' from include/linux/btf_ids.h to tools/include/linux/btf_ids.h. We don't sync the rest of the file at the moment, b/c that would require to also sync multiple dependent headers and we don't need any other defs from btf_ids.h. Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Daniel Xu <dxu@dxuuu.xyz> Link: https://lore.kernel.org/bpf/ff7f062ddf6a00815fda3087957c4ce667f50532.1707223196.git.vmalik@redhat.com
2023-06-05tools/resolve_btfids: Fix setting HOSTCFLAGSViktor Malik-2/+2
Building BPF selftests with custom HOSTCFLAGS yields an error: # make HOSTCFLAGS="-O2" [...] HOSTCC ./tools/testing/selftests/bpf/tools/build/resolve_btfids/main.o main.c:73:10: fatal error: linux/rbtree.h: No such file or directory 73 | #include <linux/rbtree.h> | ^~~~~~~~~~~~~~~~ The reason is that tools/bpf/resolve_btfids/Makefile passes header include paths by extending HOSTCFLAGS which is overridden by setting HOSTCFLAGS in the make command (because of Makefile rules [1]). This patch fixes the above problem by passing the include paths via `HOSTCFLAGS_resolve_btfids` which is used by tools/build/Build.include and can be combined with overridding HOSTCFLAGS. [1] https://www.gnu.org/software/make/manual/html_node/Overriding.html Fixes: 56a2df7615fa ("tools/resolve_btfids: Compile resolve_btfids as host program") Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20230530123352.1308488-1-vmalik@redhat.com
2023-04-27Merge tag 'mm-nonmm-stable-2023-04-27-16-01' of ↵Linus Torvalds-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Mainly singleton patches all over the place. Series of note are: - updates to scripts/gdb from Glenn Washburn - kexec cleanups from Bjorn Helgaas" * tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits) mailmap: add entries for Paul Mackerras libgcc: add forward declarations for generic library routines mailmap: add entry for Oleksandr ocfs2: reduce ioctl stack usage fs/proc: add Kthread flag to /proc/$pid/status ia64: fix an addr to taddr in huge_pte_offset() checkpatch: introduce proper bindings license check epoll: rename global epmutex scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry() scripts/gdb: create linux/vfs.py for VFS related GDB helpers uapi/linux/const.h: prefer ISO-friendly __typeof__ delayacct: track delays from IRQ/SOFTIRQ scripts/gdb: timerlist: convert int chunks to str scripts/gdb: print interrupts scripts/gdb: raise error with reduced debugging information scripts/gdb: add a Radix Tree Parser lib/rbtree: use '+' instead of '|' for setting color. proc/stat: remove arch_idle_time() checkpatch: check for misuse of the link tags checkpatch: allow Closes tags with links ...
2023-04-08ELF: fix all "Elf" typosAlexey Dobriyan-1/+1
ELF is acronym and therefore should be spelled in all caps. I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like being written in the first person. Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-06tools/resolve_btfids: Add /libsubcmd to .gitignoreRong Tao-0/+1
Add libsubcmd to .gitignore, otherwise after compiling the kernel it would result in the following: # bpf-next...bpf-next/master ?? tools/bpf/resolve_btfids/libsubcmd/ Signed-off-by: Rong Tao <rongtao@cestc.cn> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/tencent_F13D670D5D7AA9C4BD868D3220921AAC090A@qq.com
2023-02-09tools/resolve_btfids: Pass HOSTCFLAGS as EXTRA_CFLAGS to prepare targetsJiri Olsa-1/+1
Thorsten reported build issue with command line that defined extra HOSTCFLAGS that were not passed into 'prepare' targets, but were used to build resolve_btfids objects. This results in build fail when these objects are linked together: /usr/bin/ld: /build.../tools/bpf/resolve_btfids//libbpf/libbpf.a(libbpf-in.o): relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a PIE \ object; recompile with -fPIE Fixing this by passing HOSTCFLAGS in EXTRA_CFLAGS as part of HOST_OVERRIDES variable for prepare targets. [1] https://lore.kernel.org/bpf/f7922132-6645-6316-5675-0ece4197bfff@leemhuis.info/ Fixes: 56a2df7615fa ("tools/resolve_btfids: Compile resolve_btfids as host program") Reported-by: Thorsten Leemhuis <linux@leemhuis.info> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Thorsten Leemhuis <linux@leemhuis.info> Acked-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/bpf/20230209143735.4112845-1-jolsa@kernel.org
2023-02-07tools/resolve_btfids: Tidy HOST_OVERRIDESIan Rogers-2/+2
Don't set EXTRA_CFLAGS to HOSTCFLAGS, ensure CROSS_COMPILE isn't passed through. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20230202224253.40283-1-irogers@google.com
2023-02-07tools/resolve_btfids: Compile resolve_btfids as host programJiri Olsa-4/+9
Making resolve_btfids to be compiled as host program so we can avoid cross compile issues as reported by Nathan. Also we no longer need HOST_OVERRIDES for BINARY target, just for 'prepare' targets. Fixes: 13e07691a16f ("tools/resolve_btfids: Alter how HOSTCC is forced") Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/bpf/20230202112839.1131892-1-jolsa@kernel.org
2023-01-25tools/resolve_btfids: Alter how HOSTCC is forcedIan Rogers-10/+7
HOSTCC is always wanted when building. Setting CC to HOSTCC happens after tools/scripts/Makefile.include is included, meaning flags are set assuming say CC is gcc, but then it can be later set to HOSTCC which may be clang. tools/scripts/Makefile.include is needed for host set up and common macros in objtool's Makefile. Rather than override CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd builds and the linkage step. This means the Makefiles don't see things like CC changing and tool flag determination, and similar, work properly. Also, clear the passed subdir as otherwise an outer build may break by inadvertently passing an inappropriate value. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20230124064324.672022-2-irogers@google.com
2023-01-25tools/resolve_btfids: Install subcmd headersIan Rogers-6/+15
Previously tools/lib/subcmd was added to the include path, switch to installing the headers and then including from that directory. This avoids dependencies on headers internal to tools/lib/subcmd. Add the missing subcmd directory to the affected #include. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20230124064324.672022-1-irogers@google.com
2022-12-15tools/resolve_btfids: Use pkg-config to locate libelfShen Jiamin-2/+6
When libelf was not installed in the standard location, it cannot be located by the current building config. Use pkg-config to help locate libelf in such cases. Signed-off-by: Shen Jiamin <shen_jiamin@comp.nus.edu.sg> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20221215044703.400139-1-shen_jiamin@comp.nus.edu.sg
2022-07-21tools/resolve_btfids: Add support for 8-byte BTF setsKumar Kartikeya Dwivedi-6/+34
A flag is a 4-byte symbol that may follow a BTF ID in a set8. This is used in the kernel to tag kfuncs in BTF sets with certain flags. Add support to adjust the sorting code so that it passes size as 8 bytes for 8-byte BTF sets. Cc: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20220721134245.2450-3-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-02-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski-1/+5
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-03tools/resolve_btfids: Do not print any commands when building silentlyNathan Chancellor-1/+5
When building with 'make -s', there is some output from resolve_btfids: $ make -sj"$(nproc)" oldconfig prepare MKDIR .../tools/bpf/resolve_btfids/libbpf/ MKDIR .../tools/bpf/resolve_btfids//libsubcmd LINK resolve_btfids Silent mode means that no information should be emitted about what is currently being done. Use the $(silent) variable from Makefile.include to avoid defining the msg macro so that there is no information printed. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220201212503.731732-1-nathan@kernel.org
2022-01-14tools/resolve_btfids: Build with host flagsConnor O'Brien-2/+4
resolve_btfids is built using $(HOSTCC) and $(HOSTLD) but does not pick up the corresponding flags. As a result, host-specific settings (such as a sysroot specified via HOSTCFLAGS=--sysroot=..., or a linker specified via HOSTLDFLAGS=-fuse-ld=...) will not be respected. Fix this by setting CFLAGS to KBUILD_HOSTCFLAGS and LDFLAGS to KBUILD_HOSTLDFLAGS. Also pass the cflags through to libbpf via EXTRA_CFLAGS to ensure that the host libbpf is built with flags consistent with resolve_btfids. Signed-off-by: Connor O'Brien <connoro@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220112002503.115968-1-connoro@google.com
2021-12-16tools/resolve_btfids: Support cross-building the kernel with clangJean-Philippe Brucker-0/+1
The CROSS_COMPILE variable may be present during resolve_btfids build if the kernel is being cross-built. Since resolve_btfids is always executed on the host, we set CC to HOSTCC in order to use the host toolchain when cross-building with GCC. But instead of a toolchain prefix, cross-build with clang uses a "-target" parameter, which Makefile.include deduces from the CROSS_COMPILE variable. In order to avoid cross-building libbpf, clear CROSS_COMPILE before building resolve_btfids. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20211216163842.829836-3-jean-philippe@linaro.org
2021-12-10Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski-2/+3
Andrii Nakryiko says: ==================== bpf-next 2021-12-10 v2 We've added 115 non-merge commits during the last 26 day(s) which contain a total of 182 files changed, 5747 insertions(+), 2564 deletions(-). The main changes are: 1) Various samples fixes, from Alexander Lobakin. 2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov. 3) A batch of new unified APIs for libbpf, logging improvements, version querying, etc. Also a batch of old deprecations for old APIs and various bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko. 4) BPF documentation reorganization and improvements, from Christoph Hellwig and Dave Tucker. 5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in libbpf, from Hengqi Chen. 6) Verifier log fixes, from Hou Tao. 7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong. 8) Extend branch record capturing to all platforms that support it, from Kajol Jain. 9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi. 10) bpftool doc-generating script improvements, from Quentin Monnet. 11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet. 12) Deprecation warning fix for perf/bpf_counter, from Song Liu. 13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf, from Tiezhu Yang. 14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song. 15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun, and others. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits) libbpf: Add "bool skipped" to struct bpf_map libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition bpftool: Switch bpf_object__load_xattr() to bpf_object__load() selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr() selftests/bpf: Add test for libbpf's custom log_buf behavior selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load() libbpf: Deprecate bpf_object__load_xattr() libbpf: Add per-program log buffer setter and getter libbpf: Preserve kernel error code and remove kprobe prog type guessing libbpf: Improve logging around BPF program loading libbpf: Allow passing user log setting through bpf_object_open_opts libbpf: Allow passing preallocated log_buf when loading BTF into kernel libbpf: Add OPTS-based bpf_btf_load() API libbpf: Fix bpf_prog_load() log_buf logic for log_level 0 samples/bpf: Remove unneeded variable bpf: Remove redundant assignment to pointer t selftests/bpf: Fix a compilation warning perf/bpf_counter: Use bpf_map_create instead of bpf_create_map samples: bpf: Fix 'unknown warning group' build warning on Clang samples: bpf: Fix xdp_sample_user.o linking with Clang ... ==================== Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02tools/resolve_btfids: Skip unresolved symbol warning for empty BTF setsKumar Kartikeya Dwivedi-3/+5
resolve_btfids prints a warning when it finds an unresolved symbol, (id == 0) in id_patch. This can be the case for BTF sets that are empty (due to disabled config options), hence printing warnings for certain builds, most recently seen in [0]. The reason behind this is because id->cnt aliases id->id in btf_id struct, leading to empty set showing up as ID 0 when we get to id_patch, which triggers the warning. Since sets are an exception here, accomodate by reusing hole in btf_id for bool is_set member, setting it to true for BTF set when setting id->cnt, and use that to skip extraneous warning. [0]: https://lore.kernel.org/all/1b99ae14-abb4-d18f-cc6a-d7e523b25542@gmail.com Before: ; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko adding symbol tcp_cubic_kfunc_ids WARN: resolve_btfids: unresolved symbol tcp_cubic_kfunc_ids patching addr 0: ID 0 [tcp_cubic_kfunc_ids] sorting addr 4: cnt 0 [tcp_cubic_kfunc_ids] update ok for net/ipv4/tcp_cubic.ko After: ; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko adding symbol tcp_cubic_kfunc_ids patching addr 0: ID 0 [tcp_cubic_kfunc_ids] sorting addr 4: cnt 0 [tcp_cubic_kfunc_ids] update ok for net/ipv4/tcp_cubic.ko Fixes: 0e32dfc80bae ("bpf: Enable TCP congestion control kfunc from modules") Reported-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20211122144742.477787-4-memxor@gmail.com
2021-11-26tools/resolve_btf_ids: Close ELF file on errorAndrii Nakryiko-2/+3
Fix one case where we don't do explicit clean up. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20211124002325.1737739-2-andrii@kernel.org
2021-10-22tools/resolve_btfids: Switch to new btf__type_cnt APIHengqi Chen-2/+2
Replace the call to btf__get_nr_types with new API btf__type_cnt. The old API will be deprecated in libbpf v0.7+. No functionality change. Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211022130623.1548429-4-hengqi.chen@gmail.com
2021-10-08tools/resolve_btfids: Install libbpf headers when buildingQuentin Monnet-7/+13
API headers from libbpf should not be accessed directly from the library's source directory. Instead, they should be exported with "make install_headers". Let's make sure that resolve_btfids installs the headers properly when building. When descending from a parent Makefile, the specific output directories for building the library and exporting the headers are configurable with LIBBPF_OUT and LIBBPF_DESTDIR, respectively. This is in addition to OUTPUT, on top of which those variables are constructed by default. Also adjust the Makefile for the BPF selftests in order to point to the (target) libbpf shared with other tools, instead of building a version specific to resolve_btfids. Remove libbpf's order-only dependencies on the include directories (they are created by libbpf and don't need to exist beforehand). Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211007194438.34443-5-quentin@isovalent.com
2021-10-05tools: Allow specifying base BTF file in resolve_btfidsKumar Kartikeya Dwivedi-9/+19
This commit allows specifying the base BTF for resolving btf id lists/sets during link time in the resolve_btfids tool. The base BTF is set to NULL if no path is passed. This allows resolving BTF ids for module kernel objects. Also, drop the --no-fail option, as it is only used in case .BTF_ids section is not present, instead make no-fail the default mode. The long option name is same as that of pahole. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-5-memxor@gmail.com
2021-09-13libbpf: Make libbpf_version.h non-auto-generatedAndrii Nakryiko-1/+0
Turn previously auto-generated libbpf_version.h header into a normal header file. This prevents various tricky Makefile integration issues, simplifies the overall build process, but also allows to further extend it with some more versioning-related APIs in the future. To prevent accidental out-of-sync versions as defined by libbpf.map and libbpf_version.h, Makefile checks their consistency at build time. Simultaneously with this change bump libbpf.map to v0.6. Also undo adding libbpf's output directory into include path for kernel/bpf/preload, bpftool, and resolve_btfids, which is not necessary because libbpf_version.h is just a normal header like any other. Fixes: 0b46b7550560 ("libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210913222309.3220849-1-andrii@kernel.org
2021-09-09libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecationsQuentin Monnet-2/+4
Introduce a macro LIBBPF_DEPRECATED_SINCE(major, minor, message) to prepare the deprecation of two API functions. This macro marks functions as deprecated when libbpf's version reaches the values passed as an argument. As part of this change libbpf_version.h header is added with recorded major (LIBBPF_MAJOR_VERSION) and minor (LIBBPF_MINOR_VERSION) libbpf version macros. They are now part of libbpf public API and can be relied upon by user code. libbpf_version.h is installed system-wide along other libbpf public headers. Due to this new build-time auto-generated header, in-kernel applications relying on libbpf (resolve_btfids, bpftool, bpf_preload) are updated to include libbpf's output directory as part of a list of include search paths. Better fix would be to use libbpf's make_install target to install public API headers, but that clean up is left out as a future improvement. The build changes were tested by building kernel (with KBUILD_OUTPUT and O= specified explicitly), bpftool, libbpf, selftests/bpf, and resolve_btfids builds. No problems were detected. Note that because of the constraints of the C preprocessor we have to write a few lines of macro magic for each version used to prepare deprecation (0.6 for now). Also, use LIBBPF_DEPRECATED_SINCE() to schedule deprecation of btf__get_from_id() and btf__load(), which are replaced by btf__load_from_kernel_by_id() and btf__load_into_kernel(), respectively, starting from future libbpf v0.6. This is part of libbpf 1.0 effort ([0]). [0] Closes: https://github.com/libbpf/libbpf/issues/278 Co-developed-by: Quentin Monnet <quentin@isovalent.com> Co-developed-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210908213226.1871016-1-andrii@kernel.org
2021-07-29tools/resolve_btfids: Emit warnings and patch zero id for missing symbolsHengqi Chen-6/+7
Kernel functions referenced by .BTF_ids may be changed from global to static and get inlined or get renamed/removed, and thus disappears from BTF. This causes kernel build failure when resolve_btfids do id patch for symbols in .BTF_ids in vmlinux. Update resolve_btfids to emit warning messages and patch zero id for missing symbols instead of aborting kernel build process. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210727132532.2473636-2-hengqi.chen@gmail.com
2021-06-18bpf: Fix libelf endian handling in resolv_btfidsTony Ambardar-0/+3
The vmlinux ".BTF_ids" ELF section is declared in btf_ids.h to hold a list of zero-filled BTF IDs, which is then patched at link-time with correct values by resolv_btfids. The section is flagged as "allocable" to preclude compression, but notably the section contents (BTF IDs) are untyped. When patching the BTF IDs, resolve_btfids writes in host-native endianness and relies on libelf for any required translation on reading and updating vmlinux. However, since the type of the .BTF_ids section content defaults to ELF_T_BYTE (i.e. unsigned char), no translation occurs. This results in incorrect patched values when cross-compiling to non-native endianness, and can manifest as kernel Oops and test failures which are difficult to troubleshoot [1]. Explicitly set the type of patched data to ELF_T_WORD, the architecture- neutral ELF type corresponding to the u32 BTF IDs. This enables libelf to transparently perform any needed endian conversions. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Frank Eigler <fche@redhat.com> Cc: Mark Wielaard <mark@klomp.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/CAPGftE_eY-Zdi3wBcgDfkz_iOr1KF10n=9mJHm1_a_PykcsoeA@mail.gmail.com [1] Link: https://lore.kernel.org/bpf/20210618061404.818569-1-Tony.Ambardar@gmail.com
2021-03-31tools/resolve_btfids: Fix warningsStanislav Fomichev-6/+5
* make eprintf static, used only in main.c * initialize ret in eprintf * remove unused *tmp v3: * remove another err (Song Liu) v2: * remove unused 'int err = -1' Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20210329223143.3659983-1-sdf@google.com
2021-02-24tools/resolve_btfids: Fix build error with older host toolchainsKun-Chuan Hsieh-0/+5
Older libelf.h and glibc elf.h might not yet define the ELF compression types. Checking and defining SHF_COMPRESSED fix the build error when compiling with older toolchains. Also, the tool resolve_btfids is compiled with host toolchain. The host toolchain is more likely to be older than the cross compile toolchain. Fixes: 51f6463aacfb ("tools/resolve_btfids: Fix sections with wrong alignment") Signed-off-by: Kun-Chuan Hsieh <jetswayss@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@redhat.com> Link: https://lore.kernel.org/bpf/20210224052752.5284-1-jetswayss@gmail.com