From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- drivers/clk/mediatek/reset.h | 72 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 drivers/clk/mediatek/reset.h (limited to 'drivers/clk/mediatek/reset.h') diff --git a/drivers/clk/mediatek/reset.h b/drivers/clk/mediatek/reset.h new file mode 100644 index 000000000..562ffd290 --- /dev/null +++ b/drivers/clk/mediatek/reset.h @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2022 MediaTek Inc. + */ + +#ifndef __DRV_CLK_MTK_RESET_H +#define __DRV_CLK_MTK_RESET_H + +#include +#include + +#define RST_NR_PER_BANK 32 + +/* Infra global controller reset set register */ +#define INFRA_RST0_SET_OFFSET 0x120 +#define INFRA_RST1_SET_OFFSET 0x130 +#define INFRA_RST2_SET_OFFSET 0x140 +#define INFRA_RST3_SET_OFFSET 0x150 +#define INFRA_RST4_SET_OFFSET 0x730 + +/** + * enum mtk_reset_version - Version of MediaTek clock reset controller. + * @MTK_RST_SIMPLE: Use the same registers for bit set and clear. + * @MTK_RST_SET_CLR: Use separate registers for bit set and clear. + * @MTK_RST_MAX: Total quantity of version for MediaTek clock reset controller. + */ +enum mtk_reset_version { + MTK_RST_SIMPLE = 0, + MTK_RST_SET_CLR, + MTK_RST_MAX, +}; + +/** + * struct mtk_clk_rst_desc - Description of MediaTek clock reset. + * @version: Reset version which is defined in enum mtk_reset_version. + * @rst_bank_ofs: Pointer to an array containing base offsets of the reset register. + * @rst_bank_nr: Quantity of reset bank. + * @rst_idx_map:Pointer to an array containing ids if input argument is index. + * This array is not necessary if our input argument does not mean index. + * @rst_idx_map_nr: Quantity of reset index map. + */ +struct mtk_clk_rst_desc { + enum mtk_reset_version version; + u16 *rst_bank_ofs; + u32 rst_bank_nr; + u16 *rst_idx_map; + u32 rst_idx_map_nr; +}; + +/** + * struct mtk_clk_rst_data - Data of MediaTek clock reset controller. + * @regmap: Pointer to base address of reset register address. + * @rcdev: Reset controller device. + * @desc: Pointer to description of the reset controller. + */ +struct mtk_clk_rst_data { + struct regmap *regmap; + struct reset_controller_dev rcdev; + const struct mtk_clk_rst_desc *desc; +}; + +/** + * mtk_register_reset_controller - Register mediatek clock reset controller with device + * @np: Pointer to device. + * @desc: Constant pointer to description of clock reset. + * + * Return: 0 on success and errorno otherwise. + */ +int mtk_register_reset_controller_with_dev(struct device *dev, + const struct mtk_clk_rst_desc *desc); + +#endif /* __DRV_CLK_MTK_RESET_H */ -- cgit v1.3.1