Use the -Wa,--gsframe flags to build the code, so GAS will generate a new .sframe section for the stack trace information. Currently, the sframe format only supports arm64 and x86_64 architectures. Add this configuration on arm64 to enable sframe unwinder in the future.
Signed-off-by: Weinan Liu <[email protected]> Signed-off-by: Dylan Hatch <[email protected]> Reviewed-by: Prasanna Kumar T S M <[email protected]> --- Makefile | 8 ++++++++ arch/Kconfig | 6 ++++++ arch/arm64/Kconfig.debug | 10 ++++++++++ arch/arm64/kernel/vdso/Makefile | 2 +- include/asm-generic/vmlinux.lds.h | 15 +++++++++++++++ 5 files changed, 40 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index b9c661913250..09972c71a3e8 100644 --- a/Makefile +++ b/Makefile @@ -1078,6 +1078,14 @@ endif # Ensure compilers do not transform certain loops into calls to wcslen() KBUILD_CFLAGS += -fno-builtin-wcslen +# build with sframe table +ifdef CONFIG_SFRAME_UNWIND_TABLE +CC_FLAGS_SFRAME := -Wa,--gsframe +KBUILD_CFLAGS += $(CC_FLAGS_SFRAME) +KBUILD_AFLAGS += $(CC_FLAGS_SFRAME) +export CC_FLAGS_SFRAME +endif + # change __FILE__ to the relative path to the source directory ifdef building_out_of_srctree KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=) diff --git a/arch/Kconfig b/arch/Kconfig index d1b4ffd6e085..4362d2f49d91 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1782,4 +1782,10 @@ config ARCH_WANTS_PRE_LINK_VMLINUX config ARCH_HAS_CPU_ATTACK_VECTORS bool +config AS_SFRAME + def_bool $(as-instr,.cfi_sections .sframe\n.cfi_startproc\n.cfi_endproc) + +config SFRAME_UNWIND_TABLE + bool + endmenu diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug index 265c4461031f..d64bf58457de 100644 --- a/arch/arm64/Kconfig.debug +++ b/arch/arm64/Kconfig.debug @@ -20,4 +20,14 @@ config ARM64_RELOC_TEST depends on m tristate "Relocation testing module" +config SFRAME_UNWINDER + bool "Sframe unwinder" + depends on AS_SFRAME + depends on 64BIT + select SFRAME_UNWIND_TABLE + help + This option enables the sframe (Simple Frame) unwinder for unwinding + kernel stack traces. It uses unwind table that is directly generated + by toolchain based on DWARF CFI information. + source "drivers/hwtracing/coresight/Kconfig" diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index 7dec05dd33b7..c60ef921956f 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -38,7 +38,7 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO CC_FLAGS_REMOVE_VDSO := $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ $(RANDSTRUCT_CFLAGS) $(KSTACK_ERASE_CFLAGS) \ $(GCC_PLUGINS_CFLAGS) \ - $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \ + $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(CC_FLAGS_SFRAME) \ -Wmissing-prototypes -Wmissing-declarations CC_FLAGS_ADD_VDSO := -O2 -mcmodel=tiny -fasynchronous-unwind-tables diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index ae2d2359b79e..4f486080e4fb 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -473,6 +473,8 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) *(.rodata1) \ } \ \ + SFRAME \ + \ /* PCI quirks */ \ .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \ BOUNDED_SECTION_PRE_LABEL(.pci_fixup_early, _pci_fixups_early, __start, __end) \ @@ -891,6 +893,19 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) #define TRACEDATA #endif +#ifdef CONFIG_SFRAME_UNWIND_TABLE +#define SFRAME \ + /* sframe */ \ + .sframe : AT(ADDR(.sframe) - LOAD_OFFSET) { \ + __start_sframe_header = .; \ + KEEP(*(.sframe)) \ + KEEP(*(.init.sframe)) \ + __stop_sframe_header = .; \ + } +#else +#define SFRAME +#endif + #ifdef CONFIG_PRINTK_INDEX #define PRINTK_INDEX \ .printk_index : AT(ADDR(.printk_index) - LOAD_OFFSET) { \ -- 2.51.0.355.g5224444f11-goog
