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, 92 insertions, 0 deletions

diff --git a/drivers/clk/qcom/common.h b/drivers/clk/qcom/common.h
new file mode 100644
index 000000000..6f2406f88
--- /dev/null
+++ b/drivers/clk/qcom/common.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2014, The Linux Foundation. All rights reserved. */
+
+#ifndef __QCOM_CLK_COMMON_H__
+#define __QCOM_CLK_COMMON_H__
+
+struct platform_device;
+struct regmap_config;
+struct clk_regmap;
+struct qcom_reset_map;
+struct regmap;
+struct freq_tbl;
+struct clk_hw;
+
+#define PLL_LOCK_COUNT_SHIFT	8
+#define PLL_LOCK_COUNT_MASK	0x3f
+#define PLL_BIAS_COUNT_SHIFT	14
+#define PLL_BIAS_COUNT_MASK	0x3f
+#define PLL_VOTE_FSM_ENA	BIT(20)
+#define PLL_VOTE_FSM_RESET	BIT(21)
+
+struct qcom_icc_hws_data {
+	int master_id;
+	int slave_id;
+	int clk_id;
+};
+
+struct qcom_cc_driver_data {
+	struct clk_alpha_pll **alpha_plls;
+	size_t num_alpha_plls;
+	const u32 *clk_cbcrs;
+	size_t num_clk_cbcrs;
+	const struct clk_rcg_dfs_data *dfs_rcgs;
+	size_t num_dfs_rcgs;
+	void (*clk_regs_configure)(struct device *dev, struct regmap *regmap);
+};
+
+struct qcom_cc_desc {
+	const struct regmap_config *config;
+	struct clk_regmap **clks;
+	size_t num_clks;
+	const struct qcom_reset_map *resets;
+	size_t num_resets;
+	struct gdsc **gdscs;
+	size_t num_gdscs;
+	struct clk_hw **clk_hws;
+	size_t num_clk_hws;
+	const struct qcom_icc_hws_data *icc_hws;
+	size_t num_icc_hws;
+	unsigned int icc_first_node_id;
+	bool use_rpm;
+	const struct qcom_cc_driver_data *driver_data;
+};
+
+/**
+ * struct parent_map - map table for source select configuration values
+ * @src: source
+ * @cfg: configuration value
+ */
+struct parent_map {
+	u8 src;
+	u8 cfg;
+};
+
+extern const struct freq_tbl *qcom_find_freq(const struct freq_tbl *f,
+					     unsigned long rate);
+extern const struct freq_tbl *qcom_find_freq_floor(const struct freq_tbl *f,
+						   unsigned long rate);
+extern const struct freq_multi_tbl *qcom_find_freq_multi(const struct freq_multi_tbl *f,
+							 unsigned long rate);
+extern void
+qcom_pll_set_fsm_mode(struct regmap *m, u32 reg, u8 bias_count, u8 lock_count);
+extern int qcom_find_src_index(struct clk_hw *hw, const struct parent_map *map,
+			       u8 src);
+extern int qcom_find_cfg_index(struct clk_hw *hw, const struct parent_map *map,
+			       u8 cfg);
+
+extern int qcom_cc_register_board_clk(struct device *dev, const char *path,
+				      const char *name, unsigned long rate);
+extern int qcom_cc_register_sleep_clk(struct device *dev);
+
+extern struct regmap *qcom_cc_map(struct platform_device *pdev,
+				  const struct qcom_cc_desc *desc);
+extern int qcom_cc_really_probe(struct device *dev,
+				const struct qcom_cc_desc *desc,
+				struct regmap *regmap);
+extern int qcom_cc_probe(struct platform_device *pdev,
+			 const struct qcom_cc_desc *desc);
+extern int qcom_cc_probe_by_index(struct platform_device *pdev, int index,
+				  const struct qcom_cc_desc *desc);
+
+#endif