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13 daysMerge tag 'objtool-urgent-2026-02-01' of ↵Linus Torvalds3-16/+25
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool fixes from Ingo Molnar: - Fix a build error on ia32-x86_64 cross builds - Replace locally open coded ALIGN_UP(), ALIGN_UP_POW2() and MAX(), which, beyond being duplicates, the ALIGN_UP_POW2() is also buggy - Fix objtool klp-diff regression caused by a recent change to the bug table format - Fix klp-build vs CONFIG_MODULE_SRCVERSION_ALL build failure * tag 'objtool-urgent-2026-02-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: livepatch/klp-build: Fix klp-build vs CONFIG_MODULE_SRCVERSION_ALL objtool/klp: Fix bug table handling for __WARN_printf() objtool: Replace custom macros in elf.c with shared ones objtool: Print bfd_vma as unsigned long long on ia32-x86_64 cross build
2026-01-30Merge tag 'rust-fixes-6.19' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull Rust fixes from Miguel Ojeda: "Toolchain and infrastructure: - Trigger rebuilds of the newly added 'proc-macro2' crate (and its dependencies) when the Rust compiler version changes - Fix error in '.rsi' targets (macro expanding single targets) under 'O=' pointing to an external (not subdir) folder - Fix off-by-one line number in 'rustdoc' KUnit tests - Add '-fdiagnostics-show-context' to GCC flags skipped by 'bindgen' - Clean objtool warning by adding one more 'noreturn' function - Clean 'libpin_init_internal.{so,dylib}' in 'mrproper' 'kernel' crate: - Fix build error when using expressions in formatting arguments - Mark 'num::Bounded::__new()' as unsafe and clean documentation accordingly - Always inline functions using 'build_assert' with arguments - Fix 'rusttest' build error providing the right 'isize_atomic_repr' type for the host 'macros' crate: - Fix 'rusttest' build error by ignoring example rust-analyzer: - Remove assertion that was not true for distributions like NixOS - Add missing dependency edges and fix editions for 'quote' and sysroot crates to provide correct IDE support DRM Tyr: - Fix build error by adding missing dependency on 'CONFIG_COMMON_CLK' Plus clean a few typos in docs and comments" * tag 'rust-fixes-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (28 commits) rust: num: bounded: clean __new documentation and comments scripts: generate_rust_analyzer: fix resolution of #[pin_data] macros drm/tyr: depend on `COMMON_CLK` to fix build error rust: sync: atomic: Provide stub for `rusttest` 32-bit hosts kbuild: rust: clean libpin_init_internal in mrproper rust: proc-macro2: rebuild if the version text changes rust: num: bounded: add missing comment for always inlined function rust: sync: refcount: always inline functions using build_assert with arguments rust: bits: always inline functions using build_assert with arguments scripts: generate_rust_analyzer: compile sysroot with correct edition scripts: generate_rust_analyzer: compile quote with correct edition scripts: generate_rust_analyzer: quote: treat `core` and `std` as dependencies scripts: generate_rust_analyzer: syn: treat `std` as a dependency scripts: generate_rust_analyzer: remove sysroot assertion rust: kbuild: give `--config-path` to `rustfmt` in `.rsi` target scripts: generate_rust_analyzer: Add pin_init_internal deps scripts: generate_rust_analyzer: Add pin_init -> compiler_builtins dep scripts: generate_rust_analyzer: Add compiler_builtins -> core dep rust: macros: ignore example with module parameters rust: num: bounded: mark __new as unsafe ...
2026-01-27objtool/klp: Fix bug table handling for __WARN_printf()Josh Poimboeuf1-3/+11
Running objtool klp-diff on a changed function which uses WARN() can fail with: vmlinux.o: error: objtool: md_run+0x866: failed to convert reloc sym '__bug_table' to its proper format The problem is that since commit 5b472b6e5bd9 ("x86_64/bug: Implement __WARN_printf()"), each __WARN_printf() call site now directly references its bug table entry. klp-diff errors out when it can't convert such section-based references to object symbols (because bug table entries don't have symbols). Luckily, klp-diff already has code to create symbols for bug table entries. Move that code earlier, before function diffing. Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files") Fixes: 5b472b6e5bd9 ("x86_64/bug: Implement __WARN_printf()") Reported-by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Link: https://patch.msgid.link/a8e0a714b9da962858842b9aecd63b4900927c88.1769406850.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2026-01-27objtool: Replace custom macros in elf.c with shared onesPetr Pavlu1-7/+6
The source file tools/objtool/elf.c defines the macros ALIGN_UP(), ALIGN_UP_POW2() and MAX(). These macros unnecessarily duplicate functionality already available under tools/include/, specifically ALIGN(), roundup_pow_of_two() and max(). More importantly, the definition of ALIGN_UP_POW2() is incorrect when the input is 1, as it results in a call to __builtin_clz(0), which produces an undefined result. This issue impacts the function elf_alloc_reloc(). When adding the first relocation to a section, the function allocates an undefined number of relocations. Replace the custom macros with the shared functionality to resolve these issues. Fixes: 2c05ca026218 ("objtool: Add elf_create_reloc() and elf_init_reloc()") Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Link: https://patch.msgid.link/20260126151356.3924887-1-petr.pavlu@suse.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2026-01-27objtool: Print bfd_vma as unsigned long long on ia32-x86_64 cross buildDmitry Safonov1-6/+8
When objtool is cross-compiled in ia32 container for x86_64 target it fails with the following errors: > disas.c: In function 'disas_print_addr_sym': > disas.c:173:38: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'bfd_vma' {aka 'long long unsigned int'} [-Werror=format=] > 173 | DINFO_FPRINTF(dinfo, "0x%lx <%s>", addr, symstr); > | ^~~~~~~~~~~~ ~~~~ > | | > | bfd_vma {aka long long unsigned int} Provide a correct printf-fmt depending on sizeof(bfd_vma). Fixes: 5d859dff266f ("objtool: Print symbol during disassembly") Signed-off-by: Dmitry Safonov <dima@arista.com> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Link: https://patch.msgid.link/20260126-objtool-ia32-v1-1-bb6feaf17566@arista.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2026-01-21objtool: Fix libopcodes linking with static librariesSasha Levin1-4/+17
Commit 436326bc525d ("objtool: fix build failure due to missing libopcodes check") tests for libopcodes using an empty main(), which passes even when static libraries lack their dependencies. This causes undefined reference errors (xmalloc, bfd_get_bits, etc.) when linking against static libopcodes without its required libbfd and libiberty. Fix by testing with an actual libopcodes symbol and trying increasingly complete library combinations until one succeeds. Fixes: 436326bc525d ("objtool: fix build failure due to missing libopcodes check") Reported-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Link: https://patch.msgid.link/20260121162532.1596238-1-sashal@kernel.org
2026-01-13objtool: fix build failure due to missing libopcodes checkSasha Levin1-10/+14
Commit 59953303827e ("objtool: Disassemble code with libopcodes instead of running objdump") added support for using libopcodes for disassembly. However, the feature detection checks for libbfd availability but then unconditionally links against libopcodes: ifeq ($(feature-libbfd),1) OBJTOOL_LDFLAGS += -lopcodes endif This causes build failures in environments where libbfd is installed but libopcodes is not, since the test-libbfd.c feature test only links against -lbfd and -ldl, not -lopcodes: /usr/bin/ld: cannot find -lopcodes: No such file or directory collect2: error: ld returned 1 exit status make[4]: *** [Makefile:109: objtool] Error 1 Additionally, the shared feature framework uses $(CC) which is the cross-compiler in cross-compilation builds. Since objtool is a host tool that links with $(HOSTCC) against host libraries, the feature detection can falsely report libopcodes as available when the cross-compiler's sysroot has it but the host system doesn't. Fix this by replacing the feature framework check with a direct inline test that uses $(HOSTCC) to compile and link a test program against libopcodes, similar to how xxhash availability is detected. Fixes: 59953303827e ("objtool: Disassemble code with libopcodes instead of running objdump") Assisted-by: claude-opus-4-5-20251101 Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251223120357.2492008-1-sashal@kernel.org
2026-01-13objtool: fix compilation failure with the x32 toolchainMikulas Patocka1-2/+2
When using the x32 toolchain, compilation fails because the printf specifier "%lx" (long), doesn't match the type of the "checksum" variable (long long). Fix this by changing the printf specifier to "%llx" and casting "checksum" to unsigned long long. Fixes: a3493b33384a ("objtool/klp: Add --debug-checksum=<funcs> to show per-instruction checksums") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/a1158c99-fe0e-a218-4b5b-ffac212489f6@redhat.com
2026-01-04objtool/rust: add one more `noreturn` Rust functionFUJITA Tomonori1-1/+2
Fix the following warning: rust/kernel.o: warning: objtool: _RNvXNtNtCs1ewLyjEZ7Le_6kernel3str9parse_intaNtNtB2_7private12FromStrRadix14from_str_radix() falls through to next function _RNvXNtNtCs1ewLyjEZ7Le_6kernel3str9parse_intaNtNtB2_7private12FromStrRadix16from_u64_negated() The commit 51d9ee90ea90 ("rust: str: add radix prefixed integer parsing functions") introduces u64::from_str_radix(), whose implementation contains a panic path for out-of-range radix values. The panic helper is core::num::from_ascii_radix_panic(). Note that radix is derived from strip_radix() here and is always within the valid range, so kernel never panics. Fixes: 51d9ee90ea90 ("rust: str: add radix prefixed integer parsing functions") Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Link: https://patch.msgid.link/20251223113538.1016078-1-fujita.tomonori@gmail.com [ Reworded typo. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-12-03objtool: Add more robust signal error handling, detect and warn about stack ↵Josh Poimboeuf4-1/+141
overflows When the kernel build fails due to an objtool segfault, the error message is a bit obtuse and confusing: make[5]: *** [scripts/Makefile.build:503: drivers/scsi/qla2xxx/qla2xxx.o] Error 139 ^^^^^^^^^ make[5]: *** Deleting file 'drivers/scsi/qla2xxx/qla2xxx.o' make[4]: *** [scripts/Makefile.build:556: drivers/scsi/qla2xxx] Error 2 make[3]: *** [scripts/Makefile.build:556: drivers/scsi] Error 2 make[2]: *** [scripts/Makefile.build:556: drivers] Error 2 make[1]: *** [/home/jpoimboe/git/linux/Makefile:2013: .] Error 2 make: *** [Makefile:248: __sub-make] Error 2 Add a signal handler to objtool which prints an error message like if the local stack has overflown (for which there's a chance as objtool makes heavy use of recursion): drivers/scsi/qla2xxx/qla2xxx.o: error: SIGSEGV: objtool stack overflow! or: drivers/scsi/qla2xxx/qla2xxx.o: error: SIGSEGV: objtool crash! Also, re-raise the signal so the core dump still gets triggered. [ mingo: Applied a build fix, added more comments and prettified the code. ] Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: David Laight <david.laight.linux@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://patch.msgid.link/mi4tihk4dbncn7belrhp6ooudhpw4vdggerktu5333w3gqf3uf@vqlhc3y667mg
2025-12-02objtool: Fix stack overflow in validate_branch()Josh Poimboeuf1-14/+13
On an allmodconfig kernel compiled with Clang, objtool is segfaulting in drivers/scsi/qla2xxx/qla2xxx.o due to a stack overflow in validate_branch(). Due in part to KASAN being enabled, the qla2xxx code has a large number of conditional jumps, causing objtool to go quite deep in its recursion. By far the biggest offender of stack usage is the recently added 'prev_state' stack variable in validate_insn(), coming in at 328 bytes. Move that variable (and its tracing usage) to handle_insn_ops() and make handle_insn_ops() noinline to keep its stack frame outside the recursive call chain. Reported-by: Nathan Chancellor <nathan@kernel.org> Fixes: fcb268b47a2f ("objtool: Trace instruction state changes during function validation") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/21bb161c23ca0d8c942a960505c0d327ca2dc7dc.1764691895.git.jpoimboe@kernel.org Closes: https://lore.kernel.org/20251201202329.GA3225984@ax162
2025-12-01objtool: Fix segfault on unknown alternativesIngo Molnar1-0/+3
So 'objtool --link -d vmlinux.o' gets surprised by this endbr64+endbr64 pattern in ___bpf_prog_run(): ___bpf_prog_run: 1e7680: ___bpf_prog_run+0x0 push %r12 1e7682: ___bpf_prog_run+0x2 mov %rdi,%r12 1e7685: ___bpf_prog_run+0x5 push %rbp 1e7686: ___bpf_prog_run+0x6 xor %ebp,%ebp 1e7688: ___bpf_prog_run+0x8 push %rbx 1e7689: ___bpf_prog_run+0x9 mov %rsi,%rbx 1e768c: ___bpf_prog_run+0xc movzbl (%rbx),%esi 1e768f: ___bpf_prog_run+0xf movzbl %sil,%edx 1e7693: ___bpf_prog_run+0x13 mov %esi,%eax 1e7695: ___bpf_prog_run+0x15 mov 0x0(,%rdx,8),%rdx 1e769d: ___bpf_prog_run+0x1d jmp 0x1e76a2 <__x86_indirect_thunk_rdx> 1e76a2: ___bpf_prog_run+0x22 endbr64 1e76a6: ___bpf_prog_run+0x26 endbr64 1e76aa: ___bpf_prog_run+0x2a mov 0x4(%rbx),%edx And crashes due to blindly dereferencing alt->insn->alt_group. Bail out on NULL ->alt_group, which produces this warning and continues with the disassembly, instead of a segfault: .git/O/vmlinux.o: warning: objtool: <alternative.1e769d>: failed to disassemble alternative Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-11-27objtool: Build with disassembly can fail when including bdf.hAlexandre Chartre1-1/+1
Building objtool with disassembly support can fail when including the bdf.h file: In file included from tools/objtool/include/objtool/arch.h:108, from check.c:14: /usr/include/bfd.h:35:2: error: #error config.h must be included before this header 35 | #error config.h must be included before this header | ^~~~~ This check is present in the bfd.h file generated from the binutils source code, but it is not necessarily present in the bfd.h file provided in a binutil package (for example, it is not present in the binutil RPM). The solution to this issue is to define the PACKAGE macro before including bfd.h. This is the solution suggested by the binutil developer in bug 14243, and it is used by other kernel tools which also use bfd.h (perf and bpf). Fixes: 59953303827ec ("objtool: Disassemble code with libopcodes instead of running objdump") Closes: https://lore.kernel.org/all/3fa261fd-3b46-4cbe-b48d-7503aabc96cb@oracle.com/ Reported-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://sourceware.org/bugzilla/show_bug.cgi?id=14243 Link: https://patch.msgid.link/20251126134519.1760889-1-alexandre.chartre@oracle.com
2025-11-24objtool: Trim trailing NOPs in alternativeAlexandre Chartre1-5/+73
When disassembling alternatives replace trailing NOPs with a single indication of the number of bytes covered with NOPs. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-31-alexandre.chartre@oracle.com
2025-11-24objtool: Add wide output for disassemblyAlexandre Chartre3-1/+96
Add the --wide option to provide a wide output when disassembling. With this option, the disassembly of alternatives is displayed side-by-side instead of one above the other. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-30-alexandre.chartre@oracle.com
2025-11-24objtool: Compact output for alternatives with one instructionAlexandre Chartre1-0/+22
When disassembling, if an instruction has alternatives which are all made of a single instruction then print each alternative on a single line (instruction + description) so that the output is more compact. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-29-alexandre.chartre@oracle.com
2025-11-24objtool: Improve naming of group alternativesAlexandre Chartre1-6/+52
Improve the naming of group alternatives by showing the feature name and flags used by the alternative. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-28-alexandre.chartre@oracle.com
2025-11-24objtool: Add Function to get the name of a CPU featureAlexandre Chartre7-1/+36
Add a function to get the name of a CPU feature. The function is architecture dependent and currently only implemented for x86. The feature names are automatically generated from the cpufeatures.h include file. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-27-alexandre.chartre@oracle.com
2025-11-21objtool: Provide access to feature and flags of group alternativesAlexandre Chartre4-1/+6
Each alternative of a group alternative depends on a specific feature and flags. Provide access to the feature/flags for each alternative as an attribute (feature) in struct alt_group. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-26-alexandre.chartre@oracle.com
2025-11-21objtool: Fix address references in alternativesAlexandre Chartre1-4/+66
When using the --disas option, alternatives are disassembled but address references in non-default alternatives can be incorrect. The problem is that alternatives are shown as if they were replacing the original code of the alternative. So if an alternative is referencing an address inside the alternative then the reference has to be adjusted to the location of the original code. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-25-alexandre.chartre@oracle.com
2025-11-21objtool: Disassemble jump table alternativesAlexandre Chartre1-6/+32
When using the --disas option, also disassemble jump tables. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-24-alexandre.chartre@oracle.com
2025-11-21objtool: Disassemble exception table alternativesAlexandre Chartre1-1/+25
When using the --disas option, also disassemble exception tables (EX_TABLE). Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-23-alexandre.chartre@oracle.com
2025-11-21objtool: Print addresses with alternative instructionsAlexandre Chartre1-12/+23
All alternatives are disassemble side-by-side when using the --disas option. However the address of each instruction is not printed because instructions from different alternatives are not necessarily aligned. Change this behavior to print the address of each instruction. Spaces will appear between instructions from the same alternative when instructions from different alternatives do not have the same alignment. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-22-alexandre.chartre@oracle.com
2025-11-21objtool: Disassemble group alternativesAlexandre Chartre1-17/+149
When using the --disas option, disassemble all group alternatives. Jump tables and exception tables (which are handled as alternatives) are not disassembled at the moment. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-21-alexandre.chartre@oracle.com
2025-11-21objtool: Print headers for alternativesAlexandre Chartre1-6/+182
When using the --disas option, objtool doesn't currently disassemble any alternative. Print an header for each alternative. This identifies places where alternatives are present but alternative code is still not disassembled at the moment. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-20-alexandre.chartre@oracle.com
2025-11-21objtool: Preserve alternatives orderAlexandre Chartre1-2/+14
Preserve the order in which alternatives are defined. Currently objtool stores alternatives in a list in reverse order. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-19-alexandre.chartre@oracle.com
2025-11-21objtool: Add the --disas=<function-pattern> actionAlexandre Chartre5-17/+53
Add the --disas=<function-pattern> actions to disassemble the specified functions. The function pattern can be a single function name (e.g. --disas foo to disassemble the function with the name "foo"), or a shell wildcard pattern (e.g. --disas foo* to disassemble all functions with a name starting with "foo"). Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-18-alexandre.chartre@oracle.com
2025-11-21objtool: Do not validate IBT for .return_sites and .call_sitesAlexandre Chartre1-0/+2
The .return_sites and .call_sites sections reference text addresses, but not with the intent to indirect branch to them, so they don't need to be validated for IBT. This is useful when running objtool on object files which already have .return_sites or .call_sites sections, for example to re-run objtool after it has reported an error or a warning. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-17-alexandre.chartre@oracle.com
2025-11-21objtool: Improve tracing of alternative instructionsAlexandre Chartre3-13/+125
When tracing function validation, improve the reporting of alternative instruction by more clearly showing the different alternatives beginning and end. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-16-alexandre.chartre@oracle.com
2025-11-21objtool: Add functions to better name alternativesAlexandre Chartre2-0/+84
Add the disas_alt_name() and disas_alt_type_name() to provide a name and a type name for an alternative. This will be used to better name alternatives when tracing their execution. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-15-alexandre.chartre@oracle.com
2025-11-21objtool: Identify the different types of alternativesAlexandre Chartre2-5/+20
Alternative code, including jump table and exception table, is represented with the same struct alternative structure. But there is no obvious way to identify whether the struct represents alternative instructions, a jump table or an exception table. So add a type to struct alternative to clearly identify the type of alternative. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-14-alexandre.chartre@oracle.com
2025-11-21objtool: Improve register reporting during function validationAlexandre Chartre5-0/+40
When tracing function validation, instruction state changes can report changes involving registers. These registers are reported with the name "r<num>" (e.g. "r3"). Print the CPU specific register name instead of a generic name (e.g. print "rbx" instead of "r3" on x86). Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-13-alexandre.chartre@oracle.com
2025-11-21objtool: Trace instruction state changes during function validationAlexandre Chartre3-1/+149
During function validation, objtool maintains a per-instruction state, in particular to track call frame information. When tracing validation, print any instruction state changes. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-12-alexandre.chartre@oracle.com
2025-11-21objtool: Add option to trace function validationAlexandre Chartre10-18/+299
Add an option to trace and have information during the validation of specified functions. Functions are specified with the --trace option which can be a single function name (e.g. --trace foo to trace the function with the name "foo"), or a shell wildcard pattern (e.g. --trace foo* to trace all functions with a name starting with "foo"). Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-11-alexandre.chartre@oracle.com
2025-11-21objtool: Record symbol name max lengthAlexandre Chartre1-0/+7
Keep track of the maximum length of symbol names. This will help formatting the code flow between different functions. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-10-alexandre.chartre@oracle.com
2025-11-21objtool: Extract code to validate instruction from the validate branch loopAlexandre Chartre1-181/+205
The code to validate a branch loops through all instructions of the branch and validate each instruction. Move the code to validate an instruction to a separated function. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-9-alexandre.chartre@oracle.com
2025-11-21objtool: Disassemble instruction on warning or backtraceAlexandre Chartre5-14/+58
When an instruction warning (WARN_INSN) or backtrace (BT_INSN) is issued, disassemble the instruction to provide more context. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-8-alexandre.chartre@oracle.com
2025-11-21objtool: Store instruction disassembly resultAlexandre Chartre1-6/+71
When disassembling an instruction store the result instead of directly printing it. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-7-alexandre.chartre@oracle.com
2025-11-21objtool: Print symbol during disassemblyAlexandre Chartre3-9/+143
Print symbols referenced during disassembly instead of just printing raw addresses. Also handle address relocation. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-6-alexandre.chartre@oracle.com
2025-11-21objtool: Disassemble code with libopcodes instead of running objdumpAlexandre Chartre11-72/+238
objtool executes the objdump command to disassemble code. Use libopcodes instead to have more control about the disassembly scope and output. If libopcodes is not present then objtool is built without disassembly support. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-4-alexandre.chartre@oracle.com
2025-11-21objtool: Create disassembly contextAlexandre Chartre4-5/+49
Create a structure to store information for disassembling functions. For now, it is just a wrapper around an objtool file. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-3-alexandre.chartre@oracle.com
2025-11-21objtool: Move disassembly functions to a separated fileAlexandre Chartre4-81/+93
objtool disassembles functions which have warnings. Move the code to do that to a dedicated file. The code is just moved, it is not changed. Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://patch.msgid.link/20251121095340.464045-2-alexandre.chartre@oracle.com
2025-11-21Revert "objtool: Warn on functions with ambiguous -ffunction-sections ↵Josh Poimboeuf2-40/+0
section names" This reverts commit 9c7dc1dd897a1cdcade9566ea4664b03fbabf4a4. The check-function-names.sh script now provides the function name checking functionality for all architectures, making the objtool check redundant. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/c7d549d4de8bd1490d106b99630eea5efc69a4dd.1763669451.git.jpoimboe@kernel.org
2025-11-21objtool: Remove second pass of .cold function correlationJosh Poimboeuf2-23/+3
The .cold function parent/child correlation logic has two passes: one in read_symbols() and one in add_jump_destinations(). The second pass was added with commit cd77849a69cf ("objtool: Fix GCC 8 cold subfunction detection for aliased functions") to ensure that if the parent symbol had aliases then the canonical symbol was chosen as the parent. That solution was rather clunky, not to mention incomplete due to the existence of alternatives and switch tables. Now that we have sym->alias, the canonical alias fix can be done much simpler in the first pass, making the second pass obsolete. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/bdab245a38000a5407f663a031f39e14c67a43d4.1763671318.git.jpoimboe@kernel.org
2025-11-21objtool: Skip non-canonical aliased symbols in add_jump_table_alts()Josh Poimboeuf1-1/+1
If a symbol has aliases, make add_jump_table_alts() skip the non-canonical ones to avoid any surprises. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/169aa17564b9aadb74897945ea74ac2eb70c5b13.1763671318.git.jpoimboe@kernel.org
2025-11-21objtool: Return canonical symbol when aliases exist in symbol finding helpersJosh Poimboeuf1-13/+13
When symbol alias ambiguity exists in the symbol finding helper functions, return the canonical sym->alias, as that's the one which gets used by validate_branch() and elsewhere. This doesn't fix any known issues, just makes the symbol alias behavior more robust. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/450470a4897706af77453ad333e18af5ebab653c.1763671318.git.jpoimboe@kernel.org
2025-11-21objtool: Don't alias undefined symbolsJosh Poimboeuf1-2/+2
Objtool is mistakenly aliasing all undefined symbols. That's obviously wrong, though it has no consequence since objtool happens to only use sym->alias for defined symbols. Fix it regardless. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/bc401173a7717757eee672fc1ca5a20451d77b86.1763671318.git.jpoimboe@kernel.org
2025-11-21objtool: Fix .cold function detection for duplicate symbolsJosh Poimboeuf2-3/+27
The objtool .cold child/parent correlation is done in two phases: first in elf_add_symbol() and later in add_jump_destinations(). The first phase is rather crude and can pick the wrong parent if there are duplicates with the same name. The second phase usually fixes that, but only if the parent has a direct jump to the child. It does *not* work if the only branch from the parent to the child is an alternative or jump table entry. Make the first phase more robust by looking for the parent in the same STT_FILE as the child. Fixes the following objtool warnings in an AutoFDO build with a large CLANG_AUTOFDO_PROFILE profile: vmlinux.o: warning: objtool: rdev_add_key() falls through to next function rdev_add_key.cold() vmlinux.o: warning: objtool: rdev_set_default_key() falls through to next function rdev_set_default_key.cold() Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/82c7b52e40efa75dd10e1c550cc75c1ce10ac2c9.1763671318.git.jpoimboe@kernel.org
2025-11-21objtool: Support Clang AUTOFDO .cold functionsJosh Poimboeuf1-1/+9
AutoFDO enables -fsplit-machine-functions which can move the cold parts of a function to a <func>.cold symbol in a .text.split.<func> section. Unlike GCC, the Clang <func>.cold symbols are not marked STT_FUNC. This confuses objtool in several ways, resulting in warnings like the following: vmlinux.o: warning: objtool: apply_retpolines.cold+0xfc: unsupported instruction in callable function vmlinux.o: warning: objtool: machine_check_poll.cold+0x2e: unsupported instruction in callable function vmlinux.o: warning: objtool: free_deferred_objects.cold+0x1f: relocation to !ENDBR: free_deferred_objects.cold+0x26 vmlinux.o: warning: objtool: rpm_idle.cold+0xe0: relocation to !ENDBR: rpm_idle.cold+0xe7 vmlinux.o: warning: objtool: tcp_rcv_state_process.cold+0x1c: relocation to !ENDBR: tcp_rcv_state_process.cold+0x23 Fix it by marking the .cold symbols as STT_FUNC. Fixes: 2fd65f7afd5a ("AutoFDO: Enable machine function split optimization for AutoFDO") Closes: https://lore.kernel.org/20251103215244.2080638-2-xur@google.com Reported-by: Rong Xu <xur@google.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: xur@google.com Tested-by: xur@google.com Link: https://patch.msgid.link/20a67326f04b2a361c031b56d58e8a803b3c5893.1763671318.git.jpoimboe@kernel.org
2025-11-18objtool: Set minimum xxhash version to 0.8Josh Poimboeuf2-2/+2
XXH3 is only supported starting with xxhash 0.8. Enforce that. Fixes: 0d83da43b1e1 ("objtool/klp: Add --checksum option to generate per-function checksums") Closes: https://lore.kernel.org/SN6PR02MB41579B83CD295C9FEE40EED6D4FCA@SN6PR02MB4157.namprd02.prod.outlook.com Reported-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/7227c94692a3a51840278744c7af31b4797c6b96.1762990139.git.jpoimboe@kernel.org