v4.19.13 snapshot.
diff --git a/arch/sparc/kernel/stacktrace.c b/arch/sparc/kernel/stacktrace.c
new file mode 100644
index 0000000..be4c14c
--- /dev/null
+++ b/arch/sparc/kernel/stacktrace.c
@@ -0,0 +1,86 @@
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/stacktrace.h>
+#include <linux/thread_info.h>
+#include <linux/ftrace.h>
+#include <linux/export.h>
+#include <asm/ptrace.h>
+#include <asm/stacktrace.h>
+
+#include "kstack.h"
+
+static void __save_stack_trace(struct thread_info *tp,
+ struct stack_trace *trace,
+ bool skip_sched)
+{
+ unsigned long ksp, fp;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ struct task_struct *t;
+ int graph = 0;
+#endif
+
+ if (tp == current_thread_info()) {
+ stack_trace_flush();
+ __asm__ __volatile__("mov %%fp, %0" : "=r" (ksp));
+ } else {
+ ksp = tp->ksp;
+ }
+
+ fp = ksp + STACK_BIAS;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ t = tp->task;
+#endif
+ do {
+ struct sparc_stackf *sf;
+ struct pt_regs *regs;
+ unsigned long pc;
+
+ if (!kstack_valid(tp, fp))
+ break;
+
+ sf = (struct sparc_stackf *) fp;
+ regs = (struct pt_regs *) (sf + 1);
+
+ if (kstack_is_trap_frame(tp, regs)) {
+ if (!(regs->tstate & TSTATE_PRIV))
+ break;
+ pc = regs->tpc;
+ fp = regs->u_regs[UREG_I6] + STACK_BIAS;
+ } else {
+ pc = sf->callers_pc;
+ fp = (unsigned long)sf->fp + STACK_BIAS;
+ }
+
+ if (trace->skip > 0)
+ trace->skip--;
+ else if (!skip_sched || !in_sched_functions(pc)) {
+ trace->entries[trace->nr_entries++] = pc;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ if ((pc + 8UL) == (unsigned long) &return_to_handler) {
+ int index = t->curr_ret_stack;
+ if (t->ret_stack && index >= graph) {
+ pc = t->ret_stack[index - graph].ret;
+ if (trace->nr_entries <
+ trace->max_entries)
+ trace->entries[trace->nr_entries++] = pc;
+ graph++;
+ }
+ }
+#endif
+ }
+ } while (trace->nr_entries < trace->max_entries);
+}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+ __save_stack_trace(current_thread_info(), trace, false);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+ struct thread_info *tp = task_thread_info(tsk);
+
+ __save_stack_trace(tp, trace, true);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_tsk);