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/misc/sram.h | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 drivers/misc/sram.h (limited to 'drivers/misc/sram.h') diff --git a/drivers/misc/sram.h b/drivers/misc/sram.h new file mode 100644 index 000000000..397205b8b --- /dev/null +++ b/drivers/misc/sram.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Defines for the SRAM driver + */ +#ifndef __SRAM_H +#define __SRAM_H + +struct sram_config { + int (*init)(void); + bool map_only_reserved; +}; + +struct sram_partition { + void __iomem *base; + + struct gen_pool *pool; + struct bin_attribute battr; + struct mutex lock; + struct list_head list; +}; + +struct sram_dev { + const struct sram_config *config; + + struct device *dev; + void __iomem *virt_base; + bool no_memory_wc; + + struct gen_pool *pool; + + struct sram_partition *partition; + u32 partitions; +}; + +struct sram_reserve { + struct list_head list; + u32 start; + u32 size; + struct resource res; + bool export; + bool pool; + bool protect_exec; + const char *label; +}; + +#ifdef CONFIG_SRAM_EXEC +int sram_check_protect_exec(struct sram_dev *sram, struct sram_reserve *block, + struct sram_partition *part); +int sram_add_protect_exec(struct sram_partition *part); +#else +static inline int sram_check_protect_exec(struct sram_dev *sram, + struct sram_reserve *block, + struct sram_partition *part) +{ + return -ENODEV; +} + +static inline int sram_add_protect_exec(struct sram_partition *part) +{ + return -ENODEV; +} +#endif /* CONFIG_SRAM_EXEC */ +#endif /* __SRAM_H */ -- cgit v1.3.1