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 --- fs/fuse/dev.h | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 110 insertions(+) create mode 100644 fs/fuse/dev.h (limited to 'fs/fuse/dev.h') diff --git a/fs/fuse/dev.h b/fs/fuse/dev.h new file mode 100644 index 000000000..8d25378c0 --- /dev/null +++ b/fs/fuse/dev.h @@ -0,0 +1,110 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _FS_FUSE_DEV_H +#define _FS_FUSE_DEV_H + +#include + +/** Maximum number of outstanding background requests */ +#define FUSE_DEFAULT_MAX_BACKGROUND 12 + +struct fuse_conn; +struct fuse_chan; +struct fuse_dev; +struct fuse_args; +struct fuse_copy_state; +struct fuse_backing_map; +struct file; +struct folio; +enum fuse_notify_code; + +struct fuse_chan_param { + unsigned int minor; + unsigned int max_write; + unsigned int max_pages; + bool io_uring_enabled; +}; + +struct fuse_chan *fuse_chan_new(void); +struct fuse_chan *fuse_dev_chan_new(void); +void fuse_chan_release(struct fuse_chan *fch); +void fuse_chan_free(struct fuse_chan *fch); +unsigned int fuse_chan_num_background(struct fuse_chan *fch); +unsigned int fuse_chan_max_background(struct fuse_chan *fch); +void fuse_chan_max_background_set(struct fuse_chan *fch, unsigned int val); +unsigned int fuse_chan_num_waiting(struct fuse_chan *fch); +void fuse_chan_set_fc(struct fuse_chan *fch, struct fuse_conn *fc); +void fuse_chan_set_initialized(struct fuse_chan *fch, struct fuse_chan_param *param); +ssize_t fuse_chan_send(struct fuse_chan *fch, struct fuse_args *args); +int fuse_chan_send_bg(struct fuse_chan *fch, struct fuse_args *args, gfp_t gfp_flags); +int fuse_chan_send_notify_reply(struct fuse_chan *fch, struct fuse_args *args, u64 unique); +void fuse_chan_resend(struct fuse_chan *fch); + +struct fuse_forget_link *fuse_alloc_forget(void); +void fuse_chan_queue_forget(struct fuse_chan *fch, struct fuse_forget_link *forget, + u64 nodeid, u64 nlookup); + +DEFINE_FREE(fuse_chan_free, struct fuse_chan *, if (_T) fuse_chan_free(_T)) + +/** + * Initialize the client device + */ +int fuse_dev_init(void); + +/** + * Cleanup the client device + */ +void fuse_dev_cleanup(void); + +void fuse_dev_install(struct fuse_dev *fud, struct fuse_chan *fch); +bool fuse_dev_verify(struct fuse_dev *fud, struct fuse_chan *fch); +void fuse_dev_put(struct fuse_dev *fud); +bool fuse_dev_is_installed(struct fuse_dev *fud); +bool fuse_dev_is_sync_init(struct fuse_dev *fud); +struct fuse_dev *fuse_dev_grab(struct file *file); + +void fuse_init_server_timeout(struct fuse_chan *fch, unsigned int timeout); + +/* Abort all requests */ +void fuse_chan_abort(struct fuse_chan *fch, bool abort_with_err); +void fuse_chan_wait_aborted(struct fuse_chan *fch); + +/** + * Acquire reference to fuse_conn + */ +struct fuse_conn *fuse_conn_get(struct fuse_conn *fc); + +/** + * Release reference to fuse_conn + */ +void fuse_conn_put(struct fuse_conn *fc); + +dev_t fuse_conn_get_id(struct fuse_conn *fc); + +void fuse_end_polls(struct fuse_conn *fc); +int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code, + unsigned int size, struct fuse_copy_state *cs); + +int fuse_backing_open(struct fuse_conn *fc, struct fuse_backing_map *map); +int fuse_backing_close(struct fuse_conn *fc, int backing_id); + +int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size); +int fuse_copy_folio(struct fuse_copy_state *cs, struct folio **foliop, + unsigned offset, unsigned count, int zeroing); +void fuse_copy_finish(struct fuse_copy_state *cs); + +#ifdef CONFIG_FUSE_IO_URING +bool fuse_uring_enabled(void); +void fuse_uring_destruct(struct fuse_chan *fch); +#else /* CONFIG_FUSE_IO_URING */ +static inline bool fuse_uring_enabled(void) +{ + return false; +} + +static inline void fuse_uring_destruct(struct fuse_chan *fch) +{ +} +#endif /* CONFIG_FUSE_IO_URING */ + +#endif /* _FS_FUSE_DEV_H */ -- cgit v1.3.1