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/dma/dw/internal.h | 101 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 drivers/dma/dw/internal.h (limited to 'drivers/dma/dw/internal.h') diff --git a/drivers/dma/dw/internal.h b/drivers/dma/dw/internal.h new file mode 100644 index 000000000..f1bd06a20 --- /dev/null +++ b/drivers/dma/dw/internal.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Driver for the Synopsys DesignWare DMA Controller + * + * Copyright (C) 2013 Intel Corporation + */ + +#ifndef _DMA_DW_INTERNAL_H +#define _DMA_DW_INTERNAL_H + +#include + +#include "regs.h" + +int do_dma_probe(struct dw_dma_chip *chip); +int do_dma_remove(struct dw_dma_chip *chip); + +void do_dw_dma_on(struct dw_dma *dw); +void do_dw_dma_off(struct dw_dma *dw); + +int do_dw_dma_disable(struct dw_dma_chip *chip); +int do_dw_dma_enable(struct dw_dma_chip *chip); + +extern bool dw_dma_filter(struct dma_chan *chan, void *param); + +#ifdef CONFIG_ACPI +void dw_dma_acpi_controller_register(struct dw_dma *dw); +void dw_dma_acpi_controller_free(struct dw_dma *dw); +#else /* !CONFIG_ACPI */ +static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {} +static inline void dw_dma_acpi_controller_free(struct dw_dma *dw) {} +#endif /* !CONFIG_ACPI */ + +struct platform_device; + +#ifdef CONFIG_OF +struct dw_dma_platform_data *dw_dma_parse_dt(struct platform_device *pdev); +void dw_dma_of_controller_register(struct dw_dma *dw); +void dw_dma_of_controller_free(struct dw_dma *dw); +#else +static inline struct dw_dma_platform_data *dw_dma_parse_dt(struct platform_device *pdev) +{ + return NULL; +} +static inline void dw_dma_of_controller_register(struct dw_dma *dw) {} +static inline void dw_dma_of_controller_free(struct dw_dma *dw) {} +#endif + +struct dw_dma_chip_pdata { + const struct dw_dma_platform_data *pdata; + int (*probe)(struct dw_dma_chip *chip); + int (*remove)(struct dw_dma_chip *chip); + struct dw_dma_chip *chip; + u8 m_master; + u8 p_master; +}; + +static __maybe_unused const struct dw_dma_chip_pdata dw_dma_chip_pdata = { + .probe = dw_dma_probe, + .remove = dw_dma_remove, + .m_master = 0, + .p_master = 1, +}; + +static const struct dw_dma_platform_data idma32_pdata = { + .nr_channels = 8, + .chan_allocation_order = CHAN_ALLOCATION_ASCENDING, + .chan_priority = CHAN_PRIORITY_ASCENDING, + .block_size = 131071, + .nr_masters = 1, + .data_width = {4}, + .multi_block = {1, 1, 1, 1, 1, 1, 1, 1}, +}; + +static __maybe_unused const struct dw_dma_chip_pdata idma32_chip_pdata = { + .pdata = &idma32_pdata, + .probe = idma32_dma_probe, + .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, +}; + +static const struct dw_dma_platform_data xbar_pdata = { + .nr_channels = 8, + .chan_allocation_order = CHAN_ALLOCATION_ASCENDING, + .chan_priority = CHAN_PRIORITY_ASCENDING, + .block_size = 131071, + .nr_masters = 1, + .data_width = {4}, + .quirks = DW_DMA_QUIRK_XBAR_PRESENT, +}; + +static __maybe_unused const struct dw_dma_chip_pdata xbar_chip_pdata = { + .pdata = &xbar_pdata, + .probe = idma32_dma_probe, + .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, +}; + +#endif /* _DMA_DW_INTERNAL_H */ -- cgit v1.3.1