riscv: stacktrace: Fixup ftrace_graph_ret_addr retp argument

commit 5c3022e4a616d800cf5f4c3a981d7992179e44a1 upstream.

The 'retp' is a pointer to the return address on the stack, so we
must pass the current return address pointer as the 'retp'
argument to ftrace_push_return_trace(). Not parent function's
return address on the stack.

Fixes: b785ec129bd9 ("riscv/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR support")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20221109064937.3643993-2-guoren@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index c2601150b91c8fe2b5ed3012b3839599a0ca05e7..811e837a8c4eec907a13f15db30c52be8cee62cc 100644 (file)
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -60,7 +60,7 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
                } else {
                        fp = frame->fp;
                        pc = ftrace_graph_ret_addr(current, NULL, frame->ra,
-                                                  (unsigned long *)(fp - 8));
+                                                  &frame->ra);
                }
 
        }