From: Masami Hiramatsu <mhiramat@kernel.org>
Date: Mon, 24 Jan 2022 17:17:54 +0900
Subject: arm64: Mark start_backtrace() notrace and NOKPROBE_SYMBOL
Git-commit: 1e0924bd09916fab795fc2a21ec1d148f24299fd
Patch-mainline: v5.17-rc2
References: git-fixes

Mark the start_backtrace() as notrace and NOKPROBE_SYMBOL
because this function is called from ftrace and lockdep to
get the caller address via return_address(). The lockdep
is used in kprobes, it should also be NOKPROBE_SYMBOL.

Fixes: b07f3499661c ("arm64: stacktrace: Move start_backtrace() out of the header")
Cc: <stable@vger.kernel.org> # 5.13.x
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/164301227374.1433152.12808232644267107415.stgit@devnote2
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ivan T. Ivanov <iivanov@suse.de>
---
 arch/arm64/kernel/stacktrace.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -33,7 +33,7 @@
  */
 
 
-void start_backtrace(struct stackframe *frame, unsigned long fp,
+notrace void start_backtrace(struct stackframe *frame, unsigned long fp,
 		     unsigned long pc)
 {
 	frame->fp = fp;
@@ -55,6 +55,7 @@ void start_backtrace(struct stackframe *
 	frame->prev_fp = 0;
 	frame->prev_type = STACK_TYPE_UNKNOWN;
 }
+NOKPROBE_SYMBOL(start_backtrace);
 
 /*
  * Unwind from one frame record (A) to the next frame record (B).