Merge branch 'master' into test

* master: (1190 commits)
  ASoC: stm32: add of dependency for stm32 drivers
  ASoC: mt8173-rt5650: fix child-node lookup
  ASoC: dapm: fix debugfs read using path->connected
  platform/x86: samsung-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
  platform/x86: ideapad-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
  platform/x86: dell-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro
  seq_file: Introduce DEFINE_SHOW_ATTRIBUTE() helper macro
  Documentation/sysctl/user.txt: fix typo
  MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns
  MAINTAINERS: update various PALM patterns
  MAINTAINERS: update "ARM/OXNAS platform support" patterns
  MAINTAINERS: update Cortina/Gemini patterns
  MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern
  MAINTAINERS: remove ANDROID ION pattern
  mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors
  mm: docs: fix parameter names mismatch
  mm: docs: fixup punctuation
  pipe: read buffer limits atomically
  pipe: simplify round_pipe_size()
  pipe: reject F_SETPIPE_SZ with size over UINT_MAX
  ...

1 files changed, 41 insertions, 0 deletions

diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
new file mode 100644
index 000000000000..d0de68d144cb
--- /dev/null
+++ b/arch/riscv/kernel/ftrace.c
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ * Copyright (C) 2017 Andes Technology Corporation
+ */
+
+#include <linux/ftrace.h>
+
+/*
+ * Most of this file is copied from arm64.
+ */
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
+			   unsigned long frame_pointer)
+{
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+	unsigned long old;
+	struct ftrace_graph_ent trace;
+	int err;
+
+	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+		return;
+
+	/*
+	 * We don't suffer access faults, so no extra fault-recovery assembly
+	 * is needed here.
+	 */
+	old = *parent;
+
+	trace.func = self_addr;
+	trace.depth = current->curr_ret_stack + 1;
+
+	if (!ftrace_graph_entry(&trace))
+		return;
+
+	err = ftrace_push_return_trace(old, self_addr, &trace.depth,
+				       frame_pointer, NULL);
+	if (err == -EBUSY)
+		return;
+	*parent = return_hooker;
+}