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, 66 insertions, 0 deletions

diff --git a/sound/soc/codecs/rt-sdw-common.h b/sound/soc/codecs/rt-sdw-common.h
new file mode 100644
index 000000000..4759516fe
--- /dev/null
+++ b/sound/soc/codecs/rt-sdw-common.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+//
+// rt-sdw-common.h
+//
+// Copyright(c) 2024 Realtek Semiconductor Corp.
+//
+
+/*
+ * This file defines common functions used with Realtek soundwire codecs.
+ */
+
+#ifndef __RT_SDW_COMMON_H__
+#define __RT_SDW_COMMON_H__
+
+#define SDCA_NUM_JACK_CODEC			0x01
+#define SDCA_NUM_MIC_ARRAY			0x02
+#define SDCA_NUM_HID				0x03
+#define SDCA_NUM_AMP				0x04
+#define RT_SDCA_CTL_SELECTED_MODE		0x01
+#define RT_SDCA_CTL_DETECTED_MODE		0x02
+#define RT_SDCA_CTL_HIDTX_CURRENT_OWNER		0x10
+#define RT_SDCA_CTL_HIDTX_MESSAGE_OFFSET	0x12
+
+struct rt_sdca_dmic_kctrl_priv {
+	unsigned int reg_base;
+	unsigned int count;
+	unsigned int max;
+	unsigned int invert;
+};
+
+#define RT_SDCA_PR_VALUE(xreg_base, xcount, xmax, xinvert) \
+	((unsigned long)&(struct rt_sdca_dmic_kctrl_priv) \
+		{.reg_base = xreg_base, .count = xcount, .max = xmax, \
+		.invert = xinvert})
+
+#define RT_SDCA_FU_CTRL(xname, reg_base, xmax, xinvert, xcount, \
+	xinfo, xget, xput) \
+{	.iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = (xname), \
+	.info = xinfo, \
+	.get = xget, \
+	.put = xput, \
+	.private_value = RT_SDCA_PR_VALUE(reg_base, xcount, xmax, xinvert)}
+
+#define RT_SDCA_EXT_TLV(xname, reg_base, xhandler_get,\
+	 xhandler_put, xcount, xmax, tlv_array, xinfo) \
+{	.iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = (xname), \
+	.access = SNDRV_CTL_ELEM_ACCESS_TLV_READ | \
+		 SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+	.tlv.p = (tlv_array), \
+	.info = xinfo, \
+	.get = xhandler_get, .put = xhandler_put, \
+	.private_value = RT_SDCA_PR_VALUE(reg_base, xcount, xmax, 0) }
+
+
+int rt_sdca_index_write(struct regmap *map, unsigned int nid,
+	unsigned int reg, unsigned int value);
+int rt_sdca_index_read(struct regmap *map, unsigned int nid,
+	unsigned int reg, unsigned int *value);
+int rt_sdca_index_update_bits(struct regmap *map,
+	unsigned int nid, unsigned int reg, unsigned int mask, unsigned int val);
+int rt_sdca_btn_type(unsigned char *buffer);
+int rt_sdca_headset_detect(struct regmap *map, unsigned int entity_id);
+int rt_sdca_button_detect(struct regmap *map, unsigned int entity_id,
+	unsigned int hid_buf_addr, unsigned int hid_id);
+
+#endif /* __RT_SDW_COMMON_H__ */