From a2265ff39861cddb2ea0b188665b444277db6958 Mon Sep 17 00:00:00 2001 From: Tiezhu Yang Date: Mon, 11 Mar 2024 22:23:47 +0800 Subject: [PATCH] objtool/LoongArch: Enable orc to be built commit 3c7266cd7bc5e7843b631fea73cb0e82111e3158 upstream. Implement arch-specific init_orc_entry(), write_orc_entry(), reg_name(), orc_type_name(), print_reg() and orc_print_dump(), then set BUILD_ORC as y to build the orc related files. Co-developed-by: Jinyang He Signed-off-by: Jinyang He Co-developed-by: Youling Tang Signed-off-by: Youling Tang Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen --- tools/arch/loongarch/include/asm/orc_types.h | 58 +++++++ tools/objtool/Makefile | 4 + tools/objtool/arch/loongarch/Build | 1 + tools/objtool/arch/loongarch/decode.c | 16 ++ tools/objtool/arch/loongarch/orc.c | 171 +++++++++++++++++++ 5 files changed, 250 insertions(+) create mode 100644 tools/arch/loongarch/include/asm/orc_types.h create mode 100644 tools/objtool/arch/loongarch/orc.c diff --git a/tools/arch/loongarch/include/asm/orc_types.h b/tools/arch/loongarch/include/asm/orc_types.h new file mode 100644 index 000000000000..caf1f71a1057 --- /dev/null +++ b/tools/arch/loongarch/include/asm/orc_types.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _ORC_TYPES_H +#define _ORC_TYPES_H + +#include + +/* + * The ORC_REG_* registers are base registers which are used to find other + * registers on the stack. + * + * ORC_REG_PREV_SP, also known as DWARF Call Frame Address (CFA), is the + * address of the previous frame: the caller's SP before it called the current + * function. + * + * ORC_REG_UNDEFINED means the corresponding register's value didn't change in + * the current frame. + * + * The most commonly used base registers are SP and FP -- which the previous SP + * is usually based on -- and PREV_SP and UNDEFINED -- which the previous FP is + * usually based on. + * + * The rest of the base registers are needed for special cases like entry code + * and GCC realigned stacks. + */ +#define ORC_REG_UNDEFINED 0 +#define ORC_REG_PREV_SP 1 +#define ORC_REG_SP 2 +#define ORC_REG_FP 3 +#define ORC_REG_MAX 4 + +#define ORC_TYPE_UNDEFINED 0 +#define ORC_TYPE_END_OF_STACK 1 +#define ORC_TYPE_CALL 2 +#define ORC_TYPE_REGS 3 +#define ORC_TYPE_REGS_PARTIAL 4 + +#ifndef __ASSEMBLY__ +/* + * This struct is more or less a vastly simplified version of the DWARF Call + * Frame Information standard. It contains only the necessary parts of DWARF + * CFI, simplified for ease of access by the in-kernel unwinder. It tells the + * unwinder how to find the previous SP and FP (and sometimes entry regs) on + * the stack for a given code address. Each instance of the struct corresponds + * to one or more code locations. + */ +struct orc_entry { + s16 sp_offset; + s16 fp_offset; + s16 ra_offset; + unsigned int sp_reg:4; + unsigned int fp_reg:4; + unsigned int ra_reg:4; + unsigned int type:3; + unsigned int signal:1; +}; +#endif /* __ASSEMBLY__ */ + +#endif /* _ORC_TYPES_H */ diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index 83b100c1e7f6..bf7f7f84ac62 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -57,6 +57,10 @@ ifeq ($(SRCARCH),x86) BUILD_ORC := y endif +ifeq ($(SRCARCH),loongarch) + BUILD_ORC := y +endif + export BUILD_ORC export srctree OUTPUT CFLAGS SRCARCH AWK include $(srctree)/tools/build/Makefile.include diff --git a/tools/objtool/arch/loongarch/Build b/tools/objtool/arch/loongarch/Build index d24d5636a5b8..1d4b784b6887 100644 --- a/tools/objtool/arch/loongarch/Build +++ b/tools/objtool/arch/loongarch/Build @@ -1,2 +1,3 @@ objtool-y += decode.o objtool-y += special.o +objtool-y += orc.o diff --git a/tools/objtool/arch/loongarch/decode.c b/tools/objtool/arch/loongarch/decode.c index ff0b53144d12..aee479d2191c 100644 --- a/tools/objtool/arch/loongarch/decode.c +++ b/tools/objtool/arch/loongarch/decode.c @@ -3,6 +3,8 @@ #include #include #include +#include +#include #ifndef EM_LOONGARCH #define EM_LOONGARCH 258 @@ -42,6 +44,20 @@ bool arch_callee_saved_reg(unsigned char reg) int arch_decode_hint_reg(u8 sp_reg, int *base) { + switch (sp_reg) { + case ORC_REG_UNDEFINED: + *base = CFI_UNDEFINED; + break; + case ORC_REG_SP: + *base = CFI_SP; + break; + case ORC_REG_FP: + *base = CFI_FP; + break; + default: + return -1; + } + return 0; } diff --git a/tools/objtool/arch/loongarch/orc.c b/tools/objtool/arch/loongarch/orc.c new file mode 100644 index 000000000000..873536d009d9 --- /dev/null +++ b/tools/objtool/arch/loongarch/orc.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include +#include + +#include +#include +#include +#include + +int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn) +{ + struct cfi_reg *fp = &cfi->regs[CFI_FP]; + struct cfi_reg *ra = &cfi->regs[CFI_RA]; + + memset(orc, 0, sizeof(*orc)); + + if (!cfi) { + /* + * This is usually either unreachable nops/traps (which don't + * trigger unreachable instruction warnings), or + * STACK_FRAME_NON_STANDARD functions. + */ + orc->type = ORC_TYPE_UNDEFINED; + return 0; + } + + switch (cfi->type) { + case UNWIND_HINT_TYPE_UNDEFINED: + orc->type = ORC_TYPE_UNDEFINED; + return 0; + case UNWIND_HINT_TYPE_END_OF_STACK: + orc->type = ORC_TYPE_END_OF_STACK; + return 0; + case UNWIND_HINT_TYPE_CALL: + orc->type = ORC_TYPE_CALL; + break; + case UNWIND_HINT_TYPE_REGS: + orc->type = ORC_TYPE_REGS; + break; + case UNWIND_HINT_TYPE_REGS_PARTIAL: + orc->type = ORC_TYPE_REGS_PARTIAL; + break; + default: + WARN_INSN(insn, "unknown unwind hint type %d", cfi->type); + return -1; + } + + orc->signal = cfi->signal; + + switch (cfi->cfa.base) { + case CFI_SP: + orc->sp_reg = ORC_REG_SP; + break; + case CFI_FP: + orc->sp_reg = ORC_REG_FP; + break; + default: + WARN_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base); + return -1; + } + + switch (fp->base) { + case CFI_UNDEFINED: + orc->fp_reg = ORC_REG_UNDEFINED; + orc->fp_offset = 0; + break; + case CFI_CFA: + orc->fp_reg = ORC_REG_PREV_SP; + orc->fp_offset = fp->offset; + break; + case CFI_FP: + orc->fp_reg = ORC_REG_FP; + break; + default: + WARN_INSN(insn, "unknown FP base reg %d", fp->base); + return -1; + } + + switch (ra->base) { + case CFI_UNDEFINED: + orc->ra_reg = ORC_REG_UNDEFINED; + orc->ra_offset = 0; + break; + case CFI_CFA: + orc->ra_reg = ORC_REG_PREV_SP; + orc->ra_offset = ra->offset; + break; + case CFI_FP: + orc->ra_reg = ORC_REG_FP; + break; + default: + WARN_INSN(insn, "unknown RA base reg %d", ra->base); + return -1; + } + + orc->sp_offset = cfi->cfa.offset; + + return 0; +} + +int write_orc_entry(struct elf *elf, struct section *orc_sec, + struct section *ip_sec, unsigned int idx, + struct section *insn_sec, unsigned long insn_off, + struct orc_entry *o) +{ + struct orc_entry *orc; + + /* populate ORC data */ + orc = (struct orc_entry *)orc_sec->data->d_buf + idx; + memcpy(orc, o, sizeof(*orc)); + + /* populate reloc for ip */ + if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx, + insn_sec, insn_off)) + return -1; + + return 0; +} + +static const char *reg_name(unsigned int reg) +{ + switch (reg) { + case ORC_REG_SP: + return "sp"; + case ORC_REG_FP: + return "fp"; + case ORC_REG_PREV_SP: + return "prevsp"; + default: + return "?"; + } +} + +static const char *orc_type_name(unsigned int type) +{ + switch (type) { + case UNWIND_HINT_TYPE_CALL: + return "call"; + case UNWIND_HINT_TYPE_REGS: + return "regs"; + case UNWIND_HINT_TYPE_REGS_PARTIAL: + return "regs (partial)"; + default: + return "?"; + } +} + +static void print_reg(unsigned int reg, int offset) +{ + if (reg == ORC_REG_UNDEFINED) + printf(" (und) "); + else + printf("%s + %3d", reg_name(reg), offset); + +} + +void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i) +{ + printf("type:%s", orc_type_name(orc[i].type)); + + printf(" sp:"); + print_reg(orc[i].sp_reg, orc[i].sp_offset); + + printf(" fp:"); + print_reg(orc[i].fp_reg, orc[i].fp_offset); + + printf(" ra:"); + print_reg(orc[i].ra_reg, orc[i].ra_offset); + + printf(" signal:%d\n", orc[i].signal); +}