ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 154 insertions, 0 deletions

diff --git a/sound/soc/meson/aiu-codec-ctrl.c b/sound/soc/meson/aiu-codec-ctrl.c
new file mode 100644
index 000000000..60bb4cdfe
--- /dev/null
+++ b/sound/soc/meson/aiu-codec-ctrl.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2020 BayLibre, SAS.
+// Author: Jerome Brunet <jbrunet@baylibre.com>
+
+#include <linux/bitfield.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+#include <dt-bindings/sound/meson-aiu.h>
+#include "aiu.h"
+#include "meson-codec-glue.h"
+
+#define CTRL_CLK_SEL		GENMASK(1, 0)
+#define CTRL_DATA_SEL_SHIFT	4
+#define CTRL_DATA_SEL		(0x3 << CTRL_DATA_SEL_SHIFT)
+
+static const char * const aiu_codec_ctrl_mux_texts[] = {
+	"DISABLED", "PCM", "I2S",
+};
+
+static int aiu_codec_ctrl_mux_put_enum(struct snd_kcontrol *kcontrol,
+				       struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_component *component = snd_soc_dapm_kcontrol_to_component(kcontrol);
+	struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_to_dapm(kcontrol);
+	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
+	unsigned int mux, changed;
+
+	if (ucontrol->value.enumerated.item[0] >= e->items)
+		return -EINVAL;
+
+	mux = snd_soc_enum_item_to_val(e, ucontrol->value.enumerated.item[0]);
+	changed = snd_soc_component_test_bits(component, e->reg,
+					      CTRL_DATA_SEL,
+					      FIELD_PREP(CTRL_DATA_SEL, mux));
+
+	if (!changed)
+		return 0;
+
+	/* Force disconnect of the mux while updating */
+	snd_soc_dapm_mux_update_power(dapm, kcontrol, 0, NULL, NULL);
+
+	/* Reset the source first */
+	snd_soc_component_update_bits(component, e->reg,
+				      CTRL_CLK_SEL |
+				      CTRL_DATA_SEL,
+				      FIELD_PREP(CTRL_CLK_SEL, 0) |
+				      FIELD_PREP(CTRL_DATA_SEL, 0));
+
+	/* Set the appropriate source */
+	snd_soc_component_update_bits(component, e->reg,
+				      CTRL_CLK_SEL |
+				      CTRL_DATA_SEL,
+				      FIELD_PREP(CTRL_CLK_SEL, mux) |
+				      FIELD_PREP(CTRL_DATA_SEL, mux));
+
+	snd_soc_dapm_mux_update_power(dapm, kcontrol, mux, e, NULL);
+
+	return 1;
+}
+
+static SOC_ENUM_SINGLE_DECL(aiu_hdmi_ctrl_mux_enum, AIU_HDMI_CLK_DATA_CTRL,
+			    CTRL_DATA_SEL_SHIFT,
+			    aiu_codec_ctrl_mux_texts);
+
+static const struct snd_kcontrol_new aiu_hdmi_ctrl_mux =
+	SOC_DAPM_ENUM_EXT("HDMI Source", aiu_hdmi_ctrl_mux_enum,
+			  snd_soc_dapm_get_enum_double,
+			  aiu_codec_ctrl_mux_put_enum);
+
+static const struct snd_soc_dapm_widget aiu_hdmi_ctrl_widgets[] = {
+	SND_SOC_DAPM_MUX("HDMI CTRL SRC", SND_SOC_NOPM, 0, 0,
+			 &aiu_hdmi_ctrl_mux),
+};
+
+static const struct snd_soc_dai_ops aiu_codec_ctrl_input_ops = {
+	.probe		= meson_codec_glue_input_dai_probe,
+	.remove		= meson_codec_glue_input_dai_remove,
+	.hw_params	= meson_codec_glue_input_hw_params,
+	.set_fmt	= meson_codec_glue_input_set_fmt,
+};
+
+static const struct snd_soc_dai_ops aiu_codec_ctrl_output_ops = {
+	.startup	= meson_codec_glue_output_startup,
+};
+
+#define AIU_CODEC_CTRL_FORMATS					\
+	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |	\
+	 SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_LE |	\
+	 SNDRV_PCM_FMTBIT_S32_LE)
+
+#define AIU_CODEC_CTRL_STREAM(xname, xsuffix)			\
+{								\
+	.stream_name	= xname " " xsuffix,			\
+	.channels_min	= 1,					\
+	.channels_max	= 8,					\
+	.rate_min       = 5512,					\
+	.rate_max	= 192000,				\
+	.formats	= AIU_CODEC_CTRL_FORMATS,		\
+}
+
+#define AIU_CODEC_CTRL_INPUT(xname) {				\
+	.name = "CODEC CTRL " xname,				\
+	.playback = AIU_CODEC_CTRL_STREAM(xname, "Playback"),	\
+	.ops = &aiu_codec_ctrl_input_ops,			\
+}
+
+#define AIU_CODEC_CTRL_OUTPUT(xname) {				\
+	.name = "CODEC CTRL " xname,				\
+	.capture = AIU_CODEC_CTRL_STREAM(xname, "Capture"),	\
+	.ops = &aiu_codec_ctrl_output_ops,			\
+}
+
+static struct snd_soc_dai_driver aiu_hdmi_ctrl_dai_drv[] = {
+	[CTRL_I2S] = AIU_CODEC_CTRL_INPUT("HDMI I2S IN"),
+	[CTRL_PCM] = AIU_CODEC_CTRL_INPUT("HDMI PCM IN"),
+	[CTRL_OUT] = AIU_CODEC_CTRL_OUTPUT("HDMI OUT"),
+};
+
+static const struct snd_soc_dapm_route aiu_hdmi_ctrl_routes[] = {
+	{ "HDMI CTRL SRC", "I2S", "HDMI I2S IN Playback" },
+	{ "HDMI CTRL SRC", "PCM", "HDMI PCM IN Playback" },
+	{ "HDMI OUT Capture", NULL, "HDMI CTRL SRC" },
+};
+
+static int aiu_hdmi_of_xlate_dai_name(struct snd_soc_component *component,
+				      const struct of_phandle_args *args,
+				      const char **dai_name)
+{
+	return aiu_of_xlate_dai_name(component, args, dai_name, AIU_HDMI);
+}
+
+static const struct snd_soc_component_driver aiu_hdmi_ctrl_component = {
+	.name			= "AIU HDMI Codec Control",
+	.dapm_widgets		= aiu_hdmi_ctrl_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(aiu_hdmi_ctrl_widgets),
+	.dapm_routes		= aiu_hdmi_ctrl_routes,
+	.num_dapm_routes	= ARRAY_SIZE(aiu_hdmi_ctrl_routes),
+	.of_xlate_dai_name	= aiu_hdmi_of_xlate_dai_name,
+	.endianness		= 1,
+#ifdef CONFIG_DEBUG_FS
+	.debugfs_prefix		= "hdmi",
+#endif
+};
+
+int aiu_hdmi_ctrl_register_component(struct device *dev)
+{
+	return snd_soc_register_component(dev, &aiu_hdmi_ctrl_component,
+					  aiu_hdmi_ctrl_dai_drv,
+					  ARRAY_SIZE(aiu_hdmi_ctrl_dai_drv));
+}
+