This series of patches adds objtool and ORC unwinder support for LoongArch. Patch 01 - 07 are from "Madhavan T. Venkataraman" [1] with minor code tweaks. The "objtool: Reorganize ORC types" patch was not added, because LoongArch cannot share `strcut orc_entry`, it also needs to include ra_offset and ra_reg. Since the changes in Patch 01 - 08 in [1] are architecture-independent, it might be better if they could be separated separately from the series of patches. ORC unwinder can get a reliable stack trace, which provides a prerequisite for the subsequent addition of livepatch support. Instruction decoder =================== To do this, an instruction decoder needs to be implemented. I have implemented a simple, table-driven decoder for LoongArch. Only a subset of the instructions needs to be fully decoded for this purpose: - Load-Store instructions - Add instructions - Branch instructions - Call instructions - Return instructions - Stack pointer authentication instruction Unwind hints ============ Unwind hints are collected in a special section. Objtool converts unwind hints to ORC data. The unwinder processes unwind hints to handle special cases mentioned above. ORC unwinder ============ Before vmlinux created, we check all metadata, find the stack operation, note stack state and create orc data. Objtool insert two sections into vmlinux. '.orc_unwind_ip' and '.orc_unwind'. (For modules, insert '.rela.orc_unwind_ip' to relocate '.orc_unwind_ip'.) Each insn has only one stack state in .orc_unwind and orc_unwind_ip hint its pc address. Through unwinding orc data, we can get stack info both kernel and module. This is a series of RFC patches, which may require long-term discussions and revisions. It is not based on the latest code but based on 6.3-rc3. Any ideas or suggestions are welcome. base-commit: e8d018dd0257f744ca50a729e3d042cf2ec9da65 (Linux 6.3-rc3) Link: [1]: https://lore.kernel.org/lkml/20230202074036.507249-1-madvenka@xxxxxxxxxxxxxxxxxxx/#r Madhavan T. Venkataraman (7): objtool: Reorganize CFI code objtool: Reorganize instruction-related code objtool: Move decode_instructions() to a separate file objtool: Reorganize Unwind hint code objtool: Reorganize ORC code objtool: Reorganize ORC kernel code objtool: Introduce STATIC_CHECK Youling Tang (16): tools: LoongArch: Copy inst.h and asm.h to tools objtool: LoongArch: Add base definition for LoongArch objtool: LoongArch: Implement decoder objtool: Add annotate_reachable() for objtools LoongArch: bug: Add reachable annotation to warning macros objtool: Add next member in struct reloc objtool: Add orc_print_dump() package objtool: Add ORC support for LoongArch LoongArch: Add ORC unwinder support LoongArch: Support R_LARCH_32_PCREL relocation type in kernel module LoongArch: Fix fpu.S objtool warning LoongArch: Annotate unwind_hint LoongArch: Move some data definitions into the .data section objtool: Add arch-specific "noreturn" function handling objtool: Make update_cfi_state() arch-specific function LoongArch: objtool: Mark non-standard object files and directories arch/loongarch/Kconfig | 2 + arch/loongarch/Kconfig.debug | 11 + arch/loongarch/Makefile | 4 + arch/loongarch/include/asm/bug.h | 1 + arch/loongarch/include/asm/module.h | 7 + arch/loongarch/include/asm/orc_types.h | 58 ++ arch/loongarch/include/asm/stackframe.h | 3 + arch/loongarch/include/asm/unwind.h | 17 +- arch/loongarch/include/asm/unwind_hints.h | 110 +++ arch/loongarch/kernel/Makefile | 3 + arch/loongarch/kernel/entry.S | 2 + arch/loongarch/kernel/fpu.S | 11 +- arch/loongarch/kernel/genex.S | 2 + arch/loongarch/kernel/head.S | 1 + arch/loongarch/kernel/module.c | 21 +- arch/loongarch/kernel/relocate_kernel.S | 12 +- arch/loongarch/kernel/setup.c | 2 + arch/loongarch/kernel/stacktrace.c | 1 + arch/loongarch/kernel/unwind_orc.c | 301 +++++++++ arch/loongarch/kernel/vmlinux.lds.S | 3 + arch/loongarch/power/Makefile | 2 + arch/loongarch/vdso/Makefile | 2 + arch/x86/include/asm/unwind.h | 5 - arch/x86/include/asm/unwind_hints.h | 86 +++ arch/x86/kernel/module.c | 7 +- arch/x86/kernel/unwind_orc.c | 268 +------- arch/x86/kernel/vmlinux.lds.S | 2 +- .../asm => include/asm-generic}/orc_lookup.h | 43 ++ include/linux/compiler.h | 9 + include/linux/objtool.h | 70 -- kernel/Makefile | 2 + kernel/orc_lookup.c | 261 ++++++++ scripts/Makefile | 5 +- tools/arch/loongarch/include/asm/asm.h | 201 ++++++ tools/arch/loongarch/include/asm/inst.h | 629 ++++++++++++++++++ tools/arch/loongarch/include/asm/orc_types.h | 58 ++ .../arch/loongarch/include/asm/unwind_hints.h | 110 +++ tools/arch/x86/include/asm/unwind_hints.h | 160 +++++ tools/include/linux/bitops.h | 10 + tools/include/linux/objtool.h | 70 -- tools/objtool/Build | 8 +- tools/objtool/Makefile | 9 +- tools/objtool/arch/loongarch/Build | 3 + tools/objtool/arch/loongarch/decode.c | 352 ++++++++++ .../arch/loongarch/include/arch/cfi_regs.h | 14 + .../objtool/arch/loongarch/include/arch/elf.h | 15 + .../arch/loongarch/include/arch/special.h | 21 + tools/objtool/arch/loongarch/orc.c | 155 +++++ tools/objtool/arch/loongarch/special.c | 25 + tools/objtool/arch/powerpc/special.c | 3 + tools/objtool/arch/x86/Build | 1 + tools/objtool/arch/x86/include/arch/elf.h | 1 + tools/objtool/arch/x86/orc.c | 164 +++++ tools/objtool/arch/x86/special.c | 4 + tools/objtool/cfi.c | 108 +++ tools/objtool/check.c | 568 +--------------- tools/objtool/decode.c | 136 ++++ tools/objtool/elf.c | 11 +- tools/objtool/include/objtool/arch.h | 3 + tools/objtool/include/objtool/cfi.h | 12 + tools/objtool/include/objtool/check.h | 97 +-- tools/objtool/include/objtool/elf.h | 1 + tools/objtool/include/objtool/insn.h | 166 +++++ tools/objtool/include/objtool/objtool.h | 3 + tools/objtool/include/objtool/orc.h | 15 + tools/objtool/include/objtool/special.h | 3 + tools/objtool/insn.c | 195 ++++++ tools/objtool/orc_dump.c | 67 +- tools/objtool/orc_gen.c | 79 +-- tools/objtool/sync-check.sh | 9 + tools/objtool/unwind_hints.c | 107 +++ 71 files changed, 3721 insertions(+), 1206 deletions(-) create mode 100644 arch/loongarch/include/asm/orc_types.h create mode 100644 arch/loongarch/include/asm/unwind_hints.h create mode 100644 arch/loongarch/kernel/unwind_orc.c rename {arch/x86/include/asm => include/asm-generic}/orc_lookup.h (50%) create mode 100644 kernel/orc_lookup.c create mode 100644 tools/arch/loongarch/include/asm/asm.h create mode 100644 tools/arch/loongarch/include/asm/inst.h create mode 100644 tools/arch/loongarch/include/asm/orc_types.h create mode 100644 tools/arch/loongarch/include/asm/unwind_hints.h create mode 100644 tools/arch/x86/include/asm/unwind_hints.h create mode 100644 tools/objtool/arch/loongarch/Build create mode 100644 tools/objtool/arch/loongarch/decode.c create mode 100644 tools/objtool/arch/loongarch/include/arch/cfi_regs.h create mode 100644 tools/objtool/arch/loongarch/include/arch/elf.h create mode 100644 tools/objtool/arch/loongarch/include/arch/special.h create mode 100644 tools/objtool/arch/loongarch/orc.c create mode 100644 tools/objtool/arch/loongarch/special.c create mode 100644 tools/objtool/arch/x86/orc.c create mode 100644 tools/objtool/cfi.c create mode 100644 tools/objtool/decode.c create mode 100644 tools/objtool/include/objtool/insn.h create mode 100644 tools/objtool/include/objtool/orc.h create mode 100644 tools/objtool/insn.c create mode 100644 tools/objtool/unwind_hints.c -- 2.39.2
