This patchset implements a generic kernel sframe-based [1] unwinder. The main goal is to support reliable stacktraces on arm64.
On x86 orc unwinder provides reliable stacktraces. But arm64 misses the required support from objtool: it cannot generate orc unwind tables for arm64. Currently, there's already a sframe unwinder proposed for userspace: [2]. Since the sframe unwind table algorithm is similar, these two proposals could integrate common functionality in the future. Currently, only GCC supports sframe. These patches are based on v6.17-rc4 and are available on github [3]. Ref: [1]: https://sourceware.org/binutils/docs/sframe-spec.html [2]: https://lore.kernel.org/lkml/[email protected]/ [3]: https://github.com/dylanbhatch/linux/tree/sframe-v2 Changes since v1: https://lore.kernel.org/live-patching/[email protected]/ - Fixed detection of sframe support in compiler (Josh, Jens) - Adapt latest sframe v2 header definition from userspace patch series (Josh) - Folded together unwinder/stacktrace patches (Prasanna) - Fix "orphan section" warnings for .init.sframe sections (Puranjay, Indu, Josh) - Build VDSO without sframe (Dylan) - Added support for modules (Weinan) Dylan Hatch (2): unwind: build kernel with sframe info unwind: add sframe v2 header Weinan Liu (4): arm64: entry: add unwind info for various kernel entries unwind: Implement generic sframe unwinder library arm64/module, unwind: Add sframe support for modules. unwind: arm64: Add reliable stacktrace with sframe unwinder. Makefile | 8 + arch/Kconfig | 6 + arch/arm64/Kconfig.debug | 10 + arch/arm64/include/asm/module.h | 6 + arch/arm64/include/asm/stacktrace/common.h | 6 + arch/arm64/kernel/entry.S | 10 + arch/arm64/kernel/module.c | 5 + arch/arm64/kernel/setup.c | 2 + arch/arm64/kernel/stacktrace.c | 102 +++++++++ arch/arm64/kernel/vdso/Makefile | 2 +- include/asm-generic/vmlinux.lds.h | 15 ++ include/linux/sframe_lookup.h | 45 ++++ kernel/Makefile | 1 + kernel/sframe.h | 75 +++++++ kernel/sframe_lookup.c | 232 +++++++++++++++++++++ 15 files changed, 524 insertions(+), 1 deletion(-) create mode 100644 include/linux/sframe_lookup.h create mode 100644 kernel/sframe.h create mode 100644 kernel/sframe_lookup.c -- 2.51.0.355.g5224444f11-goog
