Changes in Build

ec496f77b4c11036cc835d6f045fb5e5ef1e6530 - Merge branch 'for-6.20/sony' into for-linus

Mon, 09 Feb 2026 17:33:26 +0100

Merge branch 'for-6.20/sony' into for-linus- Support for Rock band 4 PS4 and PS5 guitars (Rosalie Wanders) List of files: /linux/tools/objtool/Build

cc4adab164b772a34b3340d644b7c4728498581e - Merge tag 'v6.19-rc1' into msm-next

Tue, 20 Jan 2026 23:06:55 +0100

Merge tag 'v6.19-rc1' into msm-nextMerge Linux 6.19-rc1 in order to catch up with other changes (e.g. UBWCconfig database defining UBWC_6).Signed-off-by: Dmitry Baryshkov List of files: /linux/tools/objtool/Build

5add3c3c280a35f7e258e9cef7607db5a2e56fdc - Merge drm/drm-next into drm-xe-next

Fri, 19 Dec 2025 11:51:22 +0100

Merge drm/drm-next into drm-xe-nextBackmerging to bring in 6.19-rc1. An important upstream bugfix andto help unblock PTL CI.Signed-off-by: Thomas Hellström List of files: /linux/tools/objtool/Build

ec439c38013550420aecc15988ae6acb670838c1 - Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after 6.19-rc1

Wed, 17 Dec 2025 06:29:38 +0100

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after 6.19-rc1Cross-merge BPF and other fixes after downstream PR.Signed-off-by: Alexei Starovoitov List of files: /linux/tools/objtool/Build

b8304863a3990d0f18c38e5b94191830a63ee1af - Merge drm/drm-next into drm-intel-next

Mon, 15 Dec 2025 14:24:02 +0100

Merge drm/drm-next into drm-intel-nextSync-up some display code needed for Async flips refactor.Signed-off-by: Rodrigo Vivi List of files: /linux/tools/objtool/Build

7f790dd21a931c61167f7bdc327aecf2cebad327 - Merge drm/drm-next into drm-misc-next

Mon, 15 Dec 2025 09:27:39 +0100

Merge drm/drm-next into drm-misc-nextLet's kickstart the v6.20 (7.0?) release cycle.Signed-off-by: Maxime Ripard List of files: /linux/tools/objtool/Build

24f171c7e145f43b9f187578e89b0982ce87e54c - Merge tag 'asoc-fix-v6.19-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

Sun, 21 Dec 2025 11:11:11 +0100

Merge tag 'asoc-fix-v6.19-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linusASoC: Fixes for v6.19We've been quite busy with fixes since the merge window, though not inany particularly exciting ways - the standout thing is the fix for _SXcontrols which were broken by a change to how we do clamping, otherwiseit's all fairly run of the mill fixes and quirks. List of files: /linux/tools/objtool/Build

84318277d6334c6981ab326d4acc87c6a6ddc9b8 - Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Mon, 15 Dec 2025 12:53:27 +0100

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixesPull in rc1 to include all changes since the merge window closed,and grab all fixes and changes from drm/drm-next.Signed-off-by: Maarten Lankhorst List of files: /linux/tools/objtool/Build

08b8ddac1f4339fbf950df45590a032578ec35f7 - Merge tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Sat, 06 Dec 2025 20:56:51 +0100

Merge tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipPull objtool fixes from Ingo Molnar: "Address various objtool scalability bugs/inefficiencies exposed by allmodconfig builds, plus improve the quality of alternatives instructions generated code and disassembly"* tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Simplify .annotate_insn code generation output some more objtool: Add more robust signal error handling, detect and warn about stack overflows objtool: Remove newlines and tabs from annotation macros objtool: Consolidate annotation macros x86/asm: Remove ANNOTATE_DATA_SPECIAL usage x86/alternative: Remove ANNOTATE_DATA_SPECIAL usage objtool: Fix stack overflow in validate_branch() List of files: /linux/tools/objtool/Build

799647ddb4c0ce1d7084fcf5b524e9a0c7728325 - objtool: Add more robust signal error handling, detect and warn about stack overflows

Wed, 03 Dec 2025 00:01:17 +0100

objtool: Add more robust signal error handling, detect and warn about stack overflowsWhen the kernel build fails due to an objtool segfault, the errormessage 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 2Add a signal handler to objtool which prints an error message like ifthe local stack has overflown (for which there's a chance as objtoolmakes 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 Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Alexandre Chartre Cc: David Laight Cc: Linus Torvalds Cc: Nathan Chancellor Cc: Peter Zijlstra Link: https://patch.msgid.link/mi4tihk4dbncn7belrhp6ooudhpw4vdggerktu5333w3gqf3uf@vqlhc3y667mg List of files: /linux/tools/objtool/Build

63e6995005be8ceb8a1d56a18df1a1a40c28356d - Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Tue, 02 Dec 2025 05:18:59 +0100

Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipPull objtool updates from Ingo Molnar: - klp-build livepatch module generation (Josh Poimboeuf) Introduce new objtool features and a klp-build script to generate livepatch modules using a source .patch as input. This builds on concepts from the longstanding out-of-tree kpatch project which began in 2012 and has been used for many years to generate livepatch modules for production kernels. However, this is a complete rewrite which incorporates hard-earned lessons from 12+ years of maintaining kpatch. Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script which injects #line directives into the source .patch to preserve the original line numbers at compile time. - Disassemble code with libopcodes instead of running objdump (Alexandre Chartre) - Disassemble support (-d option to objtool) by Alexandre Chartre, which supports the decoding of various Linux kernel code generation specials such as alternatives: 17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx 17f3: sched_balance_find_dst_group+0x633 | | X86_FEATURE_POPCNT 17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax 17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx ... jump table alternatives: 1895: sched_use_asym_prio+0x5 test $0x8,%ch 1898: sched_use_asym_prio+0x8 je 0x18a9 189a: sched_use_asym_prio+0xa | | JUMP 189a: sched_use_asym_prio+0xa | jmp 0x18ae | nop2 189c: sched_use_asym_prio+0xc mov $0x1,%eax 18a1: sched_use_asym_prio+0x11 and $0x80,%ecx ... exception table alternatives: native_read_msr: 5b80: native_read_msr+0x0 mov %edi,%ecx 5b82: native_read_msr+0x2 | | EXCEPTION 5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 5b84: native_read_msr+0x4 shl $0x20,%rdx .... x86 feature flag decoding (also see the X86_FEATURE_POPCNT example in sched_balance_find_dst_group() above): 2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 2fab5: start_thread_common.constprop.0+0x25 | | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG 2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 | nop5 2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax ... NOP sequence shortening: 1048e2: snapshot_write_finalize+0xc2 je 0x104917 1048e4: snapshot_write_finalize+0xc4 nop6 1048ea: snapshot_write_finalize+0xca nop11 1048f5: snapshot_write_finalize+0xd5 nop11 104900: snapshot_write_finalize+0xe0 mov %rax,%rcx 104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax ... and much more. - Function validation tracing support (Alexandre Chartre) - Various -ffunction-sections fixes (Josh Poimboeuf) - Clang AutoFDO (Automated Feedback-Directed Optimizations) support (Josh Poimboeuf) - Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra, Thorsten Blum)* tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) objtool: Fix segfault on unknown alternatives objtool: Build with disassembly can fail when including bdf.h objtool: Trim trailing NOPs in alternative objtool: Add wide output for disassembly objtool: Compact output for alternatives with one instruction objtool: Improve naming of group alternatives objtool: Add Function to get the name of a CPU feature objtool: Provide access to feature and flags of group alternatives objtool: Fix address references in alternatives objtool: Disassemble jump table alternatives objtool: Disassemble exception table alternatives objtool: Print addresses with alternative instructions objtool: Disassemble group alternatives objtool: Print headers for alternatives objtool: Preserve alternatives order objtool: Add the --disas= action objtool: Do not validate IBT for .return_sites and .call_sites objtool: Improve tracing of alternative instructions objtool: Add functions to better name alternatives objtool: Identify the different types of alternatives ... List of files: /linux/tools/objtool/Build

70589843b36fee0c6e73632469da4e5fd11f0968 - objtool: Add option to trace function validation

Fri, 21 Nov 2025 10:53:20 +0100

objtool: Add option to trace function validationAdd an option to trace and have information during the validationof specified functions. Functions are specified with the --traceoption which can be a single function name (e.g. --trace foo totrace the function with the name "foo"), or a shell wildcardpattern (e.g. --trace foo* to trace all functions with a namestarting with "foo").Signed-off-by: Alexandre Chartre Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://patch.msgid.link/20251121095340.464045-11-alexandre.chartre@oracle.com List of files: /linux/tools/objtool/Build

59953303827eceb06d486ba66cc0d71f55ded8ec - objtool: Disassemble code with libopcodes instead of running objdump

Fri, 21 Nov 2025 10:53:13 +0100

objtool: Disassemble code with libopcodes instead of running objdumpobjtool executes the objdump command to disassemble code. Use libopcodesinstead to have more control about the disassembly scope and output.If libopcodes is not present then objtool is built without disassemblysupport.Signed-off-by: Alexandre Chartre Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://patch.msgid.link/20251121095340.464045-4-alexandre.chartre@oracle.com List of files: /linux/tools/objtool/Build

55d2a473f317ab028d78a5c5ca69473643657c3d - objtool: Move disassembly functions to a separated file

Fri, 21 Nov 2025 10:53:11 +0100

objtool: Move disassembly functions to a separated fileobjtool disassembles functions which have warnings. Move the codeto do that to a dedicated file. The code is just moved, it is notchanged.Signed-off-by: Alexandre Chartre Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://patch.msgid.link/20251121095340.464045-2-alexandre.chartre@oracle.com List of files: /linux/tools/objtool/Build

2ace52718376fdb56aca863da2eebe70d7e2ddb1 - Merge branch 'objtool/core'

Fri, 21 Nov 2025 11:21:20 +0100

Merge branch 'objtool/core'Bring in the UDB and objtool data annotations to avoid conflicts while further extending the bug exceptions.Signed-off-by: Peter Zijlstra List of files: /linux/tools/objtool/Build

00a155c691befdb10bea52c91d4c8c930bdaf73a - Merge branch 'objtool/core' of https://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux

Thu, 16 Oct 2025 11:38:19 +0200

Merge branch 'objtool/core' of https://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linuxThis series introduces new objtool features and a klp-build script togenerate livepatch modules using a source .patch as input.This builds on concepts from the longstanding out-of-tree kpatch [1]project which began in 2012 and has been used for many years to generatelivepatch modules for production kernels. However, this is a completerewrite which incorporates hard-earned lessons from 12+ years ofmaintaining kpatch.Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script which injects #line directives into the source .patch to preserve the original line numbers at compile time.The primary user interface is the klp-build script which does thefollowing: - Builds an original kernel with -function-sections and -fdata-sections, plus objtool function checksumming. - Applies the .patch file and rebuilds the kernel using the same options. - Runs 'objtool klp diff' to detect changed functions and generate intermediate binary diff objects. - Builds a kernel module which links the diff objects with some livepatch module init code (scripts/livepatch/init.c). - Finalizes the livepatch module (aka work around linker wreckage) using 'objtool klp post-link'.I've tested with a variety of patches on defconfig and Fedora-configkernels with both GCC and Clang. List of files: /linux/tools/objtool/Build

ebe864b55304f74c4e1a8b6c899e34446b2be424 - objtool/klp: Add post-link subcommand to finalize livepatch modules

Wed, 17 Sep 2025 18:04:01 +0200

objtool/klp: Add post-link subcommand to finalize livepatch modulesLivepatch needs some ELF magic which linkers don't like: - Two relocation sections (.rela*, .klp.rela*) for the same text section. - Use of SHN_LIVEPATCH to mark livepatch symbols.Unfortunately linkers tend to mangle such things. To work around that,klp diff generates a linker-compliant intermediate binary which encodesthe relevant KLP section/reloc/symbol metadata.After module linking, the .ko then needs to be converted to an actuallivepatch module. Introduce a new klp post-link subcommand to do so.Acked-by: Petr Mladek Tested-by: Joe Lawrence Signed-off-by: Josh Poimboeuf List of files: /linux/tools/objtool/Build

dd590d4d57ebeeb826823c288741f2ed20f452af - objtool/klp: Introduce klp diff subcommand for diffing object files

Wed, 17 Sep 2025 18:03:59 +0200

objtool/klp: Introduce klp diff subcommand for diffing object filesAdd a new klp diff subcommand which performs a binary diff between twoobject files and extracts changed functions into a new object which canthen be linked into a livepatch module.This builds on concepts from the longstanding out-of-tree kpatch [1]project which began in 2012 and has been used for many years to generatelivepatch modules for production kernels. However, this is a completerewrite which incorporates hard-earned lessons from 12+ years ofmaintaining kpatch.Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script (coming in a later patch) which injects #line directives into the source .patch to preserve the original line numbers at compile time.Note the end result of this subcommand is not yet functionally complete.Livepatch needs some ELF magic which linkers don't like: - Two relocation sections (.rela*, .klp.rela*) for the same text section. - Use of SHN_LIVEPATCH to mark livepatch symbols.Unfortunately linkers tend to mangle such things. To work around that,klp diff generates a linker-compliant intermediate binary which encodesthe relevant KLP section/reloc/symbol metadata.After module linking, a klp post-link step (coming soon) will clean upthe mess and convert the linked .ko into a fully compliant livepatchmodule.Note this subcommand requires the diffed binaries to have been compiledwith -ffunction-sections and -fdata-sections, and processed with'objtool --checksum'. Those constraints will be handled by a klp-buildscript introduced in a later patch.Without '-ffunction-sections -fdata-sections', reliable object diffingwould be infeasible due to toolchain limitations: - For intra-file+intra-section references, the compiler might occasionally generated hard-coded instruction offsets instead of relocations. - Section-symbol-based references can be ambiguous: - Overlapping or zero-length symbols create ambiguity as to which symbol is being referenced. - A reference to the end of a symbol (e.g., checking array bounds) can be misinterpreted as a reference to the next symbol, or vice versa.A potential future alternative to '-ffunction-sections -fdata-sections'would be to introduce a toolchain option that forces symbol-based(non-section) relocations.Acked-by: Petr Mladek Tested-by: Joe Lawrence Signed-off-by: Josh Poimboeuf List of files: /linux/tools/objtool/Build

9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e - Merge branch 'next' into for-linus

Tue, 02 May 2023 00:20:08 +0200

Merge branch 'next' into for-linusPrepare input updates for 6.4 merge window. List of files: /linux/tools/objtool/Build

cdc780f044a803aff8845b949f800f0f3d095d5f - Merge branch 'for-6.4/amd-sfh' into for-linus

Wed, 26 Apr 2023 22:52:34 +0200

Merge branch 'for-6.4/amd-sfh' into for-linus- assorted functional fixes for amd-sfh driver (Basavaraj Natikar) List of files: /linux/tools/objtool/Build