3 files changed, 41 insertions, 11 deletions

diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h
index 90f9d3399b2a..3418d32d4fc7 100644
--- a/arch/loongarch/include/asm/ftrace.h
+++ b/arch/loongarch/include/asm/ftrace.h
@@ -10,8 +10,6 @@
 #define FTRACE_REGS_PLT_IDX	1
 #define NR_FTRACE_PLTS		2
 
-#define GRAPH_FAKE_OFFSET (sizeof(struct pt_regs) - offsetof(struct pt_regs, regs[1]))
-
 #ifdef CONFIG_FUNCTION_TRACER
 
 #define MCOUNT_INSN_SIZE 4		/* sizeof mcount call */
diff --git a/arch/loongarch/include/asm/inst.h b/arch/loongarch/include/asm/inst.h
index c00e1512d4fa..7eedd83fd0d7 100644
--- a/arch/loongarch/include/asm/inst.h
+++ b/arch/loongarch/include/asm/inst.h
@@ -377,14 +377,6 @@ static inline bool unsigned_imm_check(unsigned long val, unsigned int bit)
 	return val < (1UL << bit);
 }
 
-static inline unsigned long sign_extend(unsigned long val, unsigned int idx)
-{
-	if (!is_imm_negative(val, idx + 1))
-		return ((1UL << idx) - 1) & val;
-	else
-		return ~((1UL << idx) - 1) | val;
-}
-
 #define DEF_EMIT_REG0I26_FORMAT(NAME, OP)				\
 static inline void emit_##NAME(union loongarch_instruction *insn,	\
 			       int offset)				\
@@ -401,6 +393,7 @@ static inline void emit_##NAME(union loongarch_instruction *insn,	\
 }
 
 DEF_EMIT_REG0I26_FORMAT(b, b_op)
+DEF_EMIT_REG0I26_FORMAT(bl, bl_op)
 
 #define DEF_EMIT_REG1I20_FORMAT(NAME, OP)				\
 static inline void emit_##NAME(union loongarch_instruction *insn,	\
diff --git a/arch/loongarch/include/asm/unwind.h b/arch/loongarch/include/asm/unwind.h
index f2b52b9ea93d..b9dce87afd2e 100644
--- a/arch/loongarch/include/asm/unwind.h
+++ b/arch/loongarch/include/asm/unwind.h
@@ -8,7 +8,9 @@
 #define _ASM_UNWIND_H
 
 #include <linux/sched.h>
+#include <linux/ftrace.h>
 
+#include <asm/ptrace.h>
 #include <asm/stacktrace.h>
 
 enum unwinder_type {
@@ -20,11 +22,13 @@ struct unwind_state {
 	char type; /* UNWINDER_XXX */
 	struct stack_info stack_info;
 	struct task_struct *task;
-	bool first, error, is_ftrace;
+	bool first, error, reset;
 	int graph_idx;
 	unsigned long sp, pc, ra;
 };
 
+bool default_next_frame(struct unwind_state *state);
+
 void unwind_start(struct unwind_state *state,
 		  struct task_struct *task, struct pt_regs *regs);
 bool unwind_next_frame(struct unwind_state *state);
@@ -40,4 +44,39 @@ static inline bool unwind_error(struct unwind_state *state)
 	return state->error;
 }
 
+#define GRAPH_FAKE_OFFSET (sizeof(struct pt_regs) - offsetof(struct pt_regs, regs[1]))
+
+static inline unsigned long unwind_graph_addr(struct unwind_state *state,
+					unsigned long pc, unsigned long cfa)
+{
+	return ftrace_graph_ret_addr(state->task, &state->graph_idx,
+				     pc, (unsigned long *)(cfa - GRAPH_FAKE_OFFSET));
+}
+
+static __always_inline void __unwind_start(struct unwind_state *state,
+					struct task_struct *task, struct pt_regs *regs)
+{
+	memset(state, 0, sizeof(*state));
+	if (regs) {
+		state->sp = regs->regs[3];
+		state->pc = regs->csr_era;
+		state->ra = regs->regs[1];
+	} else if (task && task != current) {
+		state->sp = thread_saved_fp(task);
+		state->pc = thread_saved_ra(task);
+		state->ra = 0;
+	} else {
+		state->sp = (unsigned long)__builtin_frame_address(0);
+		state->pc = (unsigned long)__builtin_return_address(0);
+		state->ra = 0;
+	}
+	state->task = task;
+	get_stack_info(state->sp, state->task, &state->stack_info);
+	state->pc = unwind_graph_addr(state, state->pc, state->sp);
+}
+
+static __always_inline unsigned long __unwind_get_return_address(struct unwind_state *state)
+{
+	return unwind_done(state) ? 0 : state->pc;
+}
 #endif /* _ASM_UNWIND_H */