ftrace: Synchronize the initialization of ftrace_opsgrafted

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 <rostedt@goodmis.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/include/sound/sof/debug.h b/include/sound/sof/debug.h
new file mode 100644
index 000000000..8b308d7e5
--- /dev/null
+++ b/include/sound/sof/debug.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * Copyright(c) 2020 Intel Corporation
+ *
+ * Author: Karol Trzcinski <karolx.trzcinski@linux.intel.com>
+ */
+
+#ifndef __INCLUDE_SOUND_SOF_DEBUG_H__
+#define __INCLUDE_SOUND_SOF_DEBUG_H__
+
+#include <sound/sof/header.h>
+
+/** ABI3.18 */
+enum sof_ipc_dbg_mem_zone {
+	SOF_IPC_MEM_ZONE_SYS		= 0,	/**< System zone */
+	SOF_IPC_MEM_ZONE_SYS_RUNTIME	= 1,	/**< System-runtime zone */
+	SOF_IPC_MEM_ZONE_RUNTIME	= 2,	/**< Runtime zone */
+	SOF_IPC_MEM_ZONE_BUFFER		= 3,	/**< Buffer zone */
+	SOF_IPC_MEM_ZONE_RUNTIME_SHARED	= 4,	/**< System runtime zone */
+	SOF_IPC_MEM_ZONE_SYS_SHARED	= 5,	/**< System shared zone */
+};
+
+/** ABI3.18 */
+struct sof_ipc_dbg_mem_usage_elem {
+	uint32_t zone;		/**< see sof_ipc_dbg_mem_zone */
+	uint32_t id;		/**< heap index within zone */
+	uint32_t used;		/**< number of bytes used in zone */
+	uint32_t free;		/**< number of bytes free to use within zone */
+	uint32_t reserved;	/**< for future use */
+} __packed;
+
+/** ABI3.18 */
+struct sof_ipc_dbg_mem_usage {
+	struct sof_ipc_reply rhdr;			/**< generic IPC reply header */
+	uint32_t reserved[4];				/**< reserved for future use */
+	uint32_t num_elems;				/**< elems[] counter */
+	struct sof_ipc_dbg_mem_usage_elem elems[];	/**< memory usage information */
+} __packed;
+
+#endif