4 files changed, 202 insertions, 14 deletions
diff --git a/tools/objtool/arch/loongarch/decode.c b/tools/objtool/arch/loongarch/decode.c
index 69b66994f2a1..b6fdc68053cc 100644
--- a/tools/objtool/arch/loongarch/decode.c
+++ b/tools/objtool/arch/loongarch/decode.c
@@ -5,10 +5,7 @@
 #include <asm/inst.h>
 #include <asm/orc_types.h>
 #include <linux/objtool_types.h>
-
-#ifndef EM_LOONGARCH
-#define EM_LOONGARCH	258
-#endif
+#include <arch/elf.h>
 
 int arch_ftrace_match(char *name)
 {
@@ -66,7 +63,7 @@ static bool is_loongarch(const struct elf *elf)
 	if (elf->ehdr.e_machine == EM_LOONGARCH)
 		return true;
 
-	WARN("unexpected ELF machine type %d", elf->ehdr.e_machine);
+	ERROR("unexpected ELF machine type %d", elf->ehdr.e_machine);
 	return false;
 }
 
@@ -330,8 +327,10 @@ const char *arch_nop_insn(int len)
 {
 	static u32 nop;
 
-	if (len != LOONGARCH_INSN_SIZE)
-		WARN("invalid NOP size: %d\n", len);
+	if (len != LOONGARCH_INSN_SIZE) {
+		ERROR("invalid NOP size: %d\n", len);
+		return NULL;
+	}
 
 	nop = LOONGARCH_INSN_NOP;
 
@@ -342,8 +341,10 @@ const char *arch_ret_insn(int len)
 {
 	static u32 ret;
 
-	if (len != LOONGARCH_INSN_SIZE)
-		WARN("invalid RET size: %d\n", len);
+	if (len != LOONGARCH_INSN_SIZE) {
+		ERROR("invalid RET size: %d\n", len);
+		return NULL;
+	}
 
 	emit_jirl((union loongarch_instruction *)&ret, LOONGARCH_GPR_RA, LOONGARCH_GPR_ZERO, 0);
 
@@ -363,3 +364,26 @@ void arch_initial_func_cfi_state(struct cfi_init_state *state)
 	state->cfa.base = CFI_SP;
 	state->cfa.offset = 0;
 }
+
+unsigned int arch_reloc_size(struct reloc *reloc)
+{
+	switch (reloc_type(reloc)) {
+	case R_LARCH_32:
+	case R_LARCH_32_PCREL:
+		return 4;
+	default:
+		return 8;
+	}
+}
+
+unsigned long arch_jump_table_sym_offset(struct reloc *reloc, struct reloc *table)
+{
+	switch (reloc_type(reloc)) {
+	case R_LARCH_32_PCREL:
+	case R_LARCH_64_PCREL:
+		return reloc->sym->offset + reloc_addend(reloc) -
+		       (reloc_offset(reloc) - reloc_offset(table));
+	default:
+		return reloc->sym->offset + reloc_addend(reloc);
+	}
+}
diff --git a/tools/objtool/arch/loongarch/include/arch/elf.h b/tools/objtool/arch/loongarch/include/arch/elf.h
index 9623d663220e..ec79062c9554 100644
--- a/tools/objtool/arch/loongarch/include/arch/elf.h
+++ b/tools/objtool/arch/loongarch/include/arch/elf.h
@@ -18,6 +18,13 @@
 #ifndef R_LARCH_32_PCREL
 #define R_LARCH_32_PCREL	99
 #endif
+#ifndef R_LARCH_64_PCREL
+#define R_LARCH_64_PCREL	109
+#endif
+
+#ifndef EM_LOONGARCH
+#define EM_LOONGARCH		258
+#endif
 
 #define R_NONE			R_LARCH_NONE
 #define R_ABS32			R_LARCH_32
diff --git a/tools/objtool/arch/loongarch/orc.c b/tools/objtool/arch/loongarch/orc.c
index 873536d009d9..b58c5ff443c9 100644
--- a/tools/objtool/arch/loongarch/orc.c
+++ b/tools/objtool/arch/loongarch/orc.c
@@ -41,7 +41,7 @@ int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruct
 		orc->type = ORC_TYPE_REGS_PARTIAL;
 		break;
 	default:
-		WARN_INSN(insn, "unknown unwind hint type %d", cfi->type);
+		ERROR_INSN(insn, "unknown unwind hint type %d", cfi->type);
 		return -1;
 	}
 
@@ -55,7 +55,7 @@ int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruct
 		orc->sp_reg = ORC_REG_FP;
 		break;
 	default:
-		WARN_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
+		ERROR_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
 		return -1;
 	}
 
@@ -72,7 +72,7 @@ int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruct
 		orc->fp_reg = ORC_REG_FP;
 		break;
 	default:
-		WARN_INSN(insn, "unknown FP base reg %d", fp->base);
+		ERROR_INSN(insn, "unknown FP base reg %d", fp->base);
 		return -1;
 	}
 
@@ -89,7 +89,7 @@ int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruct
 		orc->ra_reg = ORC_REG_FP;
 		break;
 	default:
-		WARN_INSN(insn, "unknown RA base reg %d", ra->base);
+		ERROR_INSN(insn, "unknown RA base reg %d", ra->base);
 		return -1;
 	}
 
diff --git a/tools/objtool/arch/loongarch/special.c b/tools/objtool/arch/loongarch/special.c
index 87230ed570fd..e39f86d97002 100644
--- a/tools/objtool/arch/loongarch/special.c
+++ b/tools/objtool/arch/loongarch/special.c
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
 #include <objtool/special.h>
+#include <objtool/warn.h>
 
 bool arch_support_alt_relocation(struct special_alt *special_alt,
 				 struct instruction *insn,
@@ -8,9 +10,164 @@ bool arch_support_alt_relocation(struct special_alt *special_alt,
 	return false;
 }
 
+struct table_info {
+	struct list_head jump_info;
+	unsigned long insn_offset;
+	unsigned long rodata_offset;
+};
+
+static void get_rodata_table_size_by_table_annotate(struct objtool_file *file,
+						    struct instruction *insn,
+						    unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+	struct list_head table_list;
+	struct table_info *orig_table;
+	struct table_info *next_table;
+	unsigned long tmp_insn_offset;
+	unsigned long tmp_rodata_offset;
+
+	rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate");
+	if (!rsec)
+		return;
+
+	INIT_LIST_HEAD(&table_list);
+
+	for_each_reloc(rsec, reloc) {
+		orig_table = malloc(sizeof(struct table_info));
+		if (!orig_table) {
+			WARN("malloc failed");
+			return;
+		}
+
+		orig_table->insn_offset = reloc->sym->offset + reloc_addend(reloc);
+		reloc++;
+		orig_table->rodata_offset = reloc->sym->offset + reloc_addend(reloc);
+
+		list_add_tail(&orig_table->jump_info, &table_list);
+
+		if (reloc_idx(reloc) + 1 == sec_num_entries(rsec))
+			break;
+	}
+
+	list_for_each_entry(orig_table, &table_list, jump_info) {
+		next_table = list_next_entry(orig_table, jump_info);
+		list_for_each_entry_from(next_table, &table_list, jump_info) {
+			if (next_table->rodata_offset < orig_table->rodata_offset) {
+				tmp_insn_offset = next_table->insn_offset;
+				tmp_rodata_offset = next_table->rodata_offset;
+				next_table->insn_offset = orig_table->insn_offset;
+				next_table->rodata_offset = orig_table->rodata_offset;
+				orig_table->insn_offset = tmp_insn_offset;
+				orig_table->rodata_offset = tmp_rodata_offset;
+			}
+		}
+	}
+
+	list_for_each_entry(orig_table, &table_list, jump_info) {
+		if (insn->offset == orig_table->insn_offset) {
+			next_table = list_next_entry(orig_table, jump_info);
+			if (&next_table->jump_info == &table_list) {
+				*table_size = 0;
+				return;
+			}
+
+			while (next_table->rodata_offset == orig_table->rodata_offset) {
+				next_table = list_next_entry(next_table, jump_info);
+				if (&next_table->jump_info == &table_list) {
+					*table_size = 0;
+					return;
+				}
+			}
+
+			*table_size = next_table->rodata_offset - orig_table->rodata_offset;
+		}
+	}
+}
+
+static struct reloc *find_reloc_by_table_annotate(struct objtool_file *file,
+						  struct instruction *insn,
+						  unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+	unsigned long offset;
+
+	rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate");
+	if (!rsec)
+		return NULL;
+
+	for_each_reloc(rsec, reloc) {
+		if (reloc->sym->sec->rodata)
+			continue;
+
+		if (strcmp(insn->sec->name, reloc->sym->sec->name))
+			continue;
+
+		offset = reloc->sym->offset + reloc_addend(reloc);
+		if (insn->offset == offset) {
+			get_rodata_table_size_by_table_annotate(file, insn, table_size);
+			reloc++;
+			return reloc;
+		}
+	}
+
+	return NULL;
+}
+
+static struct reloc *find_reloc_of_rodata_c_jump_table(struct section *sec,
+						       unsigned long offset,
+						       unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+
+	rsec = sec->rsec;
+	if (!rsec)
+		return NULL;
+
+	for_each_reloc(rsec, reloc) {
+		if (reloc_offset(reloc) > offset)
+			break;
+
+		if (!strcmp(reloc->sym->sec->name, C_JUMP_TABLE_SECTION)) {
+			*table_size = 0;
+			return reloc;
+		}
+	}
+
+	return NULL;
+}
+
 struct reloc *arch_find_switch_table(struct objtool_file *file,
 				     struct instruction *insn,
 				     unsigned long *table_size)
 {
-	return NULL;
+	struct reloc *annotate_reloc;
+	struct reloc *rodata_reloc;
+	struct section *table_sec;
+	unsigned long table_offset;
+
+	annotate_reloc = find_reloc_by_table_annotate(file, insn, table_size);
+	if (!annotate_reloc) {
+		annotate_reloc = find_reloc_of_rodata_c_jump_table(
+				 insn->sec, insn->offset, table_size);
+		if (!annotate_reloc)
+			return NULL;
+	}
+
+	table_sec = annotate_reloc->sym->sec;
+	table_offset = annotate_reloc->sym->offset + reloc_addend(annotate_reloc);
+
+	/*
+	 * Each table entry has a rela associated with it.  The rela
+	 * should reference text in the same function as the original
+	 * instruction.
+	 */
+	rodata_reloc = find_reloc_by_dest(file->elf, table_sec, table_offset);
+	if (!rodata_reloc)
+		return NULL;
+
+	return rodata_reloc;
 }