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 --- sound/firewire/fcp.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 sound/firewire/fcp.h (limited to 'sound/firewire/fcp.h') diff --git a/sound/firewire/fcp.h b/sound/firewire/fcp.h new file mode 100644 index 000000000..512f7c409 --- /dev/null +++ b/sound/firewire/fcp.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef SOUND_FIREWIRE_FCP_H_INCLUDED +#define SOUND_FIREWIRE_FCP_H_INCLUDED + +#define AVC_PLUG_INFO_BUF_BYTES 4 + +struct fw_unit; + +/* + * AV/C Digital Interface Command Set General Specification 4.2 + * (Sep 2004, 1394TA) + */ +enum avc_general_plug_dir { + AVC_GENERAL_PLUG_DIR_IN = 0, + AVC_GENERAL_PLUG_DIR_OUT = 1, + AVC_GENERAL_PLUG_DIR_COUNT +}; +int avc_general_set_sig_fmt(struct fw_unit *unit, unsigned int rate, + enum avc_general_plug_dir dir, + unsigned short plug); +int avc_general_get_sig_fmt(struct fw_unit *unit, unsigned int *rate, + enum avc_general_plug_dir dir, + unsigned short plug); +int avc_general_get_plug_info(struct fw_unit *unit, unsigned int subunit_type, + unsigned int subunit_id, unsigned int subfunction, + u8 info[AVC_PLUG_INFO_BUF_BYTES]); + +int fcp_avc_transaction(struct fw_unit *unit, + const void *command, unsigned int command_size, + void *response, unsigned int response_size, + unsigned int response_match_bytes); +void fcp_bus_reset(struct fw_unit *unit); + +#endif -- cgit v1.3.1