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/mtd/ubi/wl.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 drivers/mtd/ubi/wl.h (limited to 'drivers/mtd/ubi/wl.h') diff --git a/drivers/mtd/ubi/wl.h b/drivers/mtd/ubi/wl.h new file mode 100644 index 000000000..a69169c35 --- /dev/null +++ b/drivers/mtd/ubi/wl.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef UBI_WL_H +#define UBI_WL_H +#ifdef CONFIG_MTD_UBI_FASTMAP +static void update_fastmap_work_fn(struct work_struct *wrk); +static struct ubi_wl_entry *find_anchor_wl_entry(struct rb_root *root); +static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi); +static struct ubi_wl_entry *next_peb_for_wl(struct ubi_device *ubi, + bool need_fill); +static bool need_wear_leveling(struct ubi_device *ubi); +static void ubi_fastmap_close(struct ubi_device *ubi); +static inline void ubi_fastmap_init(struct ubi_device *ubi, int *count) +{ + if (ubi->fm_disabled) + ubi->fm_pool_rsv_cnt = 0; + /* Reserve enough LEBs to store two fastmaps and to fill pools. */ + *count += (ubi->fm_size / ubi->leb_size) * 2 + ubi->fm_pool_rsv_cnt; + INIT_WORK(&ubi->fm_work, update_fastmap_work_fn); +} +static struct ubi_wl_entry *may_reserve_for_fm(struct ubi_device *ubi, + struct ubi_wl_entry *e, + struct rb_root *root); +#else /* !CONFIG_MTD_UBI_FASTMAP */ +static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi); +static inline void ubi_fastmap_close(struct ubi_device *ubi) { } +static inline void ubi_fastmap_init(struct ubi_device *ubi, int *count) { } +static struct ubi_wl_entry *may_reserve_for_fm(struct ubi_device *ubi, + struct ubi_wl_entry *e, + struct rb_root *root) { + return e; +} +#endif /* CONFIG_MTD_UBI_FASTMAP */ +#endif /* UBI_WL_H */ -- cgit v1.3.1