Changes in klp-checksum.c

d8d706a27451c015490d23b4f4764de05e553624 - Merge tag 'objtool-core-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

Mon, 15 Jun 2026 11:01:58 +0200

Merge tag 'objtool-core-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tipPull objtool updates from Ingo Molnar: - A large series of KLP fixes and improvements, in preparation of the arm64 port (Josh Poimboeuf) - Fix a number of bugs and issues on specific distro, LTO, FineIBT and kCFI configs (Josh Poimboeuf) - Misc other fixes by Josh Poimboeuf and Joe Lawrence* tag 'objtool-core-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (53 commits) objtool/klp: Cache dont_correlate() result objtool: Improve and simplify prefix symbol detection objtool/klp: Fix kCFI prefix finding/cloning objtool: Grow __cfi_* prefix symbols for all CFI+CALL_PADDING objtool/klp: Fix position-dependent checksums for non-relocated jumps/calls objtool: Add insn_sym() helper objtool/klp: Add correlation debugging output objtool/klp: Rewrite symbol correlation algorithm objtool/klp: Calculate object checksums klp-build: Validate short-circuit prerequisites objtool/klp: Remove "objtool --checksum" klp-build: Use "objtool klp checksum" subcommand objtool/klp: Add "objtool klp checksum" subcommand objtool: Consolidate file decoding into decode_file() objtool/klp: Extricate checksum calculation from validate_branch() objtool: Add is_cold_func() helper objtool: Add is_alias_sym() helper objtool/klp: Handle Clang .data..Lanon anonymous data sections objtool/klp: Create empty checksum sections for function-less object files objtool: Include libsubcmd headers directly from source tree ... List of files: /linux/tools/objtool/klp-checksum.c

cca84cb12908f1cfcecaef80a7692017e2d6a945 - objtool/klp: Fix position-dependent checksums for non-relocated jumps/calls

Fri, 03 Apr 2026 20:57:02 +0200

objtool/klp: Fix position-dependent checksums for non-relocated jumps/callsWhen computing klp checksums, instructions with non-relocated jump/calldestination offsets are problematic because the offset values can changewhen surrounding code has moved, causing the function to be incorrectlymarked as changed.Specifically, that includes jumps from alternatives to the end of thealternative, which from objtool's perspective are jumps to the end ofthe alternative instruction block in the original function.Note that 'jump_dest' jumps don't include sibling calls (those usecall_dest), nor do they include jumps to/from .cold sub functions (thoseare cross-section and need a reloc).Fix it by hashing the opcode bytes (excluding the immediate operand)along with a position-independent representation of the destination.For calls, use the function name, and for jumps, use the destination'soffset within its function.[Note the "9 bit hole" comment was wrong: it has been 8 bits sincecommit 70589843b36f ("objtool: Add option to trace function validation")added the 'trace' field. Adding the 4-bit 'immediate_len' field nowleaves a 4-bit hole.]Fixes: 0d83da43b1e1 ("objtool/klp: Add --checksum option to generate per-function checksums")Acked-by: Song Liu Signed-off-by: Josh Poimboeuf List of files: /linux/tools/objtool/klp-checksum.c

873a2208ea31e822e0a5eea86b8a3fd07208db45 - objtool/klp: Calculate object checksums

Thu, 16 Apr 2026 07:49:53 +0200

objtool/klp: Calculate object checksumsStart checksumming data objects in preparation for revamping thecorrelation algorithm.Acked-by: Song Liu Signed-off-by: Josh Poimboeuf List of files: /linux/tools/objtool/klp-checksum.c

e10764614ad634071d3bc8cfbf8bce43285d458d - objtool/klp: Add "objtool klp checksum" subcommand

Fri, 03 Apr 2026 22:08:32 +0200

objtool/klp: Add "objtool klp checksum" subcommandMove the checksum functionality out of the main objtool command into anew "objtool klp checksum" subcommand.This has the benefit of making the code (and the patch generationprocess itself) more modular.For bisectability, both "objtool --checksum" and "objtool klp checksum"work for now. The former will be removed after klp-build has beenconverted to use the new subcommand.Acked-by: Song Liu Signed-off-by: Josh Poimboeuf List of files: /linux/tools/objtool/klp-checksum.c