Merge tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes updates from Masami Hiramatsu:

 - fprobe: Pass return address to the fprobe entry/exit callbacks so
   that the callbacks don't need to analyze pt_regs/stack to find the
   function return address.

 - kprobe events: cleanup usage of TPARG_FL_FENTRY and TPARG_FL_RETURN
   flags so that those are not set at once.

 - fprobe events:
      - Add a new fprobe events for tracing arbitrary function entry and
        exit as a trace event.
      - Add a new tracepoint events for tracing raw tracepoint as a
        trace event. This allows user to trace non user-exposed
        tracepoints.
      - Move eprobe's event parser code into probe event common file.
      - Introduce BTF (BPF type format) support to kernel probe (kprobe,
        fprobe and tracepoint probe) events so that user can specify
        traced function arguments by name. This also applies the type of
        argument when fetching the argument.
      - Introduce '$arg*' wildcard support if BTF is available. This
        expands the '$arg*' meta argument to all function argument
        automatically.
      - Check the return value types by BTF. If the function returns
        'void', '$retval' is rejected.
      - Add some selftest script for fprobe events, tracepoint events
        and BTF support.
      - Update documentation about the fprobe events.
      - Some fixes for above features, document and selftests.

 - selftests for ftrace (in addition to the new fprobe events):
      - Add a test case for multiple consecutive probes in a function
        which checks if ftrace based kprobe, optimized kprobe and normal
        kprobe can be defined in the same target function.
      - Add a test case for optimized probe, which checks whether kprobe
        can be optimized or not.

* tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix tracepoint event with $arg* to fetch correct argument
  Documentation: Fix typo of reference file name
  tracing/probes: Fix to return NULL and keep using current argc
  selftests/ftrace: Add new test case which checks for optimized probes
  selftests/ftrace: Add new test case which adds multiple consecutive probes in a function
  Documentation: tracing/probes: Add fprobe event tracing document
  selftests/ftrace: Add BTF arguments test cases
  selftests/ftrace: Add tracepoint probe test case
  tracing/probes: Add BTF retval type support
  tracing/probes: Add $arg* meta argument for all function args
  tracing/probes: Support function parameters if BTF is available
  tracing/probes: Move event parameter fetching code to common parser
  tracing/probes: Add tracepoint support on fprobe_events
  selftests/ftrace: Add fprobe related testcases
  tracing/probes: Add fprobe events for tracing function entry and exit.
  tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN
  fprobe: Pass return address to the handlers

14 files changed, 1917 insertions, 155 deletions

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 00e177de91cc..ce13f1a35251 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2127,6 +2127,7 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
 NOKPROBE_SYMBOL(pre_handler_kretprobe);
 
 static void kretprobe_rethook_handler(struct rethook_node *rh, void *data,
+				      unsigned long ret_addr,
 				      struct pt_regs *regs)
 {
 	struct kretprobe *rp = (struct kretprobe *)data;
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index abe5c583bd59..61c541c36596 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -665,6 +665,32 @@ config BLK_DEV_IO_TRACE
 
 	  If unsure, say N.
 
+config FPROBE_EVENTS
+	depends on FPROBE
+	depends on HAVE_REGS_AND_STACK_ACCESS_API
+	bool "Enable fprobe-based dynamic events"
+	select TRACING
+	select PROBE_EVENTS
+	select DYNAMIC_EVENTS
+	default y
+	help
+	  This allows user to add tracing events on the function entry and
+	  exit via ftrace interface. The syntax is same as the kprobe events
+	  and the kprobe events on function entry and exit will be
+	  transparently converted to this fprobe events.
+
+config PROBE_EVENTS_BTF_ARGS
+	depends on HAVE_FUNCTION_ARG_ACCESS_API
+	depends on FPROBE_EVENTS || KPROBE_EVENTS
+	depends on DEBUG_INFO_BTF && BPF_SYSCALL
+	bool "Support BTF function arguments for probe events"
+	default y
+	help
+	  The user can specify the arguments of the probe event using the names
+	  of the arguments of the probed function, when the probe location is a
+	  kernel function entry or a tracepoint.
+	  This is available only if BTF (BPF Type Format) support is enabled.
+
 config KPROBE_EVENTS
 	depends on KPROBES
 	depends on HAVE_REGS_AND_STACK_ACCESS_API
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index c6651e16b557..64b61f67a403 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -104,6 +104,7 @@ obj-$(CONFIG_BOOTTIME_TRACING) += trace_boot.o
 obj-$(CONFIG_FTRACE_RECORD_RECURSION) += trace_recursion_record.o
 obj-$(CONFIG_FPROBE) += fprobe.o
 obj-$(CONFIG_RETHOOK) += rethook.o
+obj-$(CONFIG_FPROBE_EVENTS) += trace_fprobe.o
 
 obj-$(CONFIG_TRACEPOINT_BENCHMARK) += trace_benchmark.o
 obj-$(CONFIG_RV) += rv/
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 03b7f6b8e4f0..5f2dcabad202 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2652,7 +2652,8 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
 
 static int
 kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
-			  struct pt_regs *regs, void *data)
+			  unsigned long ret_ip, struct pt_regs *regs,
+			  void *data)
 {
 	struct bpf_kprobe_multi_link *link;
 
@@ -2663,7 +2664,8 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
 
 static void
 kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip,
-			       struct pt_regs *regs, void *data)
+			       unsigned long ret_ip, struct pt_regs *regs,
+			       void *data)
 {
 	struct bpf_kprobe_multi_link *link;
 
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 18d36842faf5..e4704ec26df7 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -46,7 +46,7 @@ static inline void __fprobe_handler(unsigned long ip, unsigned long parent_ip,
 	}
 
 	if (fp->entry_handler)
-		ret = fp->entry_handler(fp, ip, ftrace_get_regs(fregs), entry_data);
+		ret = fp->entry_handler(fp, ip, parent_ip, ftrace_get_regs(fregs), entry_data);
 
 	/* If entry_handler returns !0, nmissed is not counted. */
 	if (rh) {
@@ -112,7 +112,7 @@ static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip,
 }
 
 static void fprobe_exit_handler(struct rethook_node *rh, void *data,
-				struct pt_regs *regs)
+				unsigned long ret_ip, struct pt_regs *regs)
 {
 	struct fprobe *fp = (struct fprobe *)data;
 	struct fprobe_rethook_node *fpr;
@@ -133,7 +133,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data,
 		return;
 	}
 
-	fp->exit_handler(fp, fpr->entry_ip, regs,
+	fp->exit_handler(fp, fpr->entry_ip, ret_ip, regs,
 			 fp->entry_data_size ? (void *)fpr->data : NULL);
 	ftrace_test_recursion_unlock(bit);
 }
@@ -348,6 +348,14 @@ int register_fprobe_syms(struct fprobe *fp, const char **syms, int num)
 }
 EXPORT_SYMBOL_GPL(register_fprobe_syms);
 
+bool fprobe_is_registered(struct fprobe *fp)
+{
+	if (!fp || (fp->ops.saved_func != fprobe_handler &&
+		    fp->ops.saved_func != fprobe_kprobe_handler))
+		return false;
+	return true;
+}
+
 /**
  * unregister_fprobe() - Unregister fprobe from ftrace
  * @fp: A fprobe data structure to be unregistered.
@@ -360,8 +368,7 @@ int unregister_fprobe(struct fprobe *fp)
 {
 	int ret;
 
-	if (!fp || (fp->ops.saved_func != fprobe_handler &&
-		    fp->ops.saved_func != fprobe_kprobe_handler))
+	if (!fprobe_is_registered(fp))
 		return -EINVAL;
 
 	/*
diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c
index 60f6cb2b486b..f32ee484391a 100644
--- a/kernel/trace/rethook.c
+++ b/kernel/trace/rethook.c
@@ -301,7 +301,8 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs,
 			break;
 		handler = READ_ONCE(rhn->rethook->handler);
 		if (handler)
-			handler(rhn, rhn->rethook->data, regs);
+			handler(rhn, rhn->rethook->data,
+				correct_ret_addr, regs);
 
 		if (first == node)
 			break;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 074d0b2e19ed..b04f52e7cd28 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5672,10 +5672,17 @@ static const char readme_msg[] =
 	"  uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n"
 	"\t\t\t  Write into this file to define/undefine new trace events.\n"
 #endif
-#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
+#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) || \
+    defined(CONFIG_FPROBE_EVENTS)
 	"\t  accepts: event-definitions (one definition per line)\n"
+#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
 	"\t   Format: p[:[<group>/][<event>]] <place> [<args>]\n"
 	"\t           r[maxactive][:[<group>/][<event>]] <place> [<args>]\n"
+#endif
+#ifdef CONFIG_FPROBE_EVENTS
+	"\t           f[:[<group>/][<event>]] <func-name>[%return] [<args>]\n"
+	"\t           t[:[<group>/][<event>]] <tracepoint> [<args>]\n"
+#endif
 #ifdef CONFIG_HIST_TRIGGERS
 	"\t           s:[synthetic/]<event> <field> [<field>]\n"
 #endif
@@ -5691,7 +5698,11 @@ static const char readme_msg[] =
 	"\t     args: <name>=fetcharg[:type]\n"
 	"\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n"
 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
+	"\t           $stack<index>, $stack, $retval, $comm, $arg<N>, <argname>\n"
+#else
 	"\t           $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
+#endif
 #else
 	"\t           $stack<index>, $stack, $retval, $comm,\n"
 #endif
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index e6407a27d644..ed7906b13f09 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -148,6 +148,17 @@ struct kretprobe_trace_entry_head {
 	unsigned long		ret_ip;
 };
 
+struct fentry_trace_entry_head {
+	struct trace_entry	ent;
+	unsigned long		ip;
+};
+
+struct fexit_trace_entry_head {
+	struct trace_entry	ent;
+	unsigned long		func;
+	unsigned long		ret_ip;
+};
+
 #define TRACE_BUF_SIZE		1024
 
 struct trace_array;
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 67e854979d53..cb0077ba2b49 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -227,37 +227,6 @@ error:
 	return ERR_PTR(ret);
 }
 
-static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i)
-{
-	struct probe_arg *parg = &ep->tp.args[i];
-	struct ftrace_event_field *field;
-	struct list_head *head;
-	int ret = -ENOENT;
-
-	head = trace_get_fields(ep->event);
-	list_for_each_entry(field, head, link) {
-		if (!strcmp(parg->code->data, field->name)) {
-			kfree(parg->code->data);
-			parg->code->data = field;
-			return 0;
-		}
-	}
-
-	/*
-	 * Argument not found on event. But allow for comm and COMM
-	 * to be used to get the current->comm.
-	 */
-	if (strcmp(parg->code->data, "COMM") == 0 ||
-	    strcmp(parg->code->data, "comm") == 0) {
-		parg->code->op = FETCH_OP_COMM;
-		ret = 0;
-	}
-
-	kfree(parg->code->data);
-	parg->code->data = NULL;
-	return ret;
-}
-
 static int eprobe_event_define_fields(struct trace_event_call *event_call)
 {
 	struct eprobe_trace_entry_head field;
@@ -817,19 +786,16 @@ find_and_get_event(const char *system, const char *event_name)
 
 static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i)
 {
-	unsigned int flags = TPARG_FL_KERNEL | TPARG_FL_TPOINT;
+	struct traceprobe_parse_context ctx = {
+		.event = ep->event,
+		.flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT,
+	};
 	int ret;
 
-	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], flags);
+	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], &ctx);
 	if (ret)
 		return ret;
 
-	if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG) {
-		ret = trace_eprobe_tp_arg_update(ep, i);
-		if (ret)
-			trace_probe_log_err(0, BAD_ATTACH_ARG);
-	}
-
 	/* Handle symbols "@" */
 	if (!ret)
 		ret = traceprobe_update_arg(&ep->tp.args[i]);
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
new file mode 100644
index 000000000000..dfe2e546acdc
--- /dev/null
+++ b/kernel/trace/trace_fprobe.c
@@ -0,0 +1,1199 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Fprobe-based tracing events
+ * Copyright (C) 2022 Google LLC.
+ */
+#define pr_fmt(fmt)	"trace_fprobe: " fmt
+
+#include <linux/fprobe.h>
+#include <linux/module.h>
+#include <linux/rculist.h>
+#include <linux/security.h>
+#include <linux/tracepoint.h>
+#include <linux/uaccess.h>
+
+#include "trace_dynevent.h"
+#include "trace_probe.h"
+#include "trace_probe_kernel.h"
+#include "trace_probe_tmpl.h"
+
+#define FPROBE_EVENT_SYSTEM "fprobes"
+#define TRACEPOINT_EVENT_SYSTEM "tracepoints"
+#define RETHOOK_MAXACTIVE_MAX 4096
+
+static int trace_fprobe_create(const char *raw_command);
+static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev);
+static int trace_fprobe_release(struct dyn_event *ev);
+static bool trace_fprobe_is_busy(struct dyn_event *ev);
+static bool trace_fprobe_match(const char *system, const char *event,
+			int argc, const char **argv, struct dyn_event *ev);
+
+static struct dyn_event_operations trace_fprobe_ops = {
+	.create = trace_fprobe_create,
+	.show = trace_fprobe_show,
+	.is_busy = trace_fprobe_is_busy,
+	.free = trace_fprobe_release,
+	.match = trace_fprobe_match,
+};
+
+/*
+ * Fprobe event core functions
+ */
+struct trace_fprobe {
+	struct dyn_event	devent;
+	struct fprobe		fp;
+	const char		*symbol;
+	struct tracepoint	*tpoint;
+	struct module		*mod;
+	struct trace_probe	tp;
+};
+
+static bool is_trace_fprobe(struct dyn_event *ev)
+{
+	return ev->ops == &trace_fprobe_ops;
+}
+
+static struct trace_fprobe *to_trace_fprobe(struct dyn_event *ev)
+{
+	return container_of(ev, struct trace_fprobe, devent);
+}
+
+/**
+ * for_each_trace_fprobe - iterate over the trace_fprobe list
+ * @pos:	the struct trace_fprobe * for each entry
+ * @dpos:	the struct dyn_event * to use as a loop cursor
+ */
+#define for_each_trace_fprobe(pos, dpos)	\
+	for_each_dyn_event(dpos)		\
+		if (is_trace_fprobe(dpos) && (pos = to_trace_fprobe(dpos)))
+
+static bool trace_fprobe_is_return(struct trace_fprobe *tf)
+{
+	return tf->fp.exit_handler != NULL;
+}
+
+static bool trace_fprobe_is_tracepoint(struct trace_fprobe *tf)
+{
+	return tf->tpoint != NULL;
+}
+
+static const char *trace_fprobe_symbol(struct trace_fprobe *tf)
+{
+	return tf->symbol ? tf->symbol : "unknown";
+}
+
+static bool trace_fprobe_is_busy(struct dyn_event *ev)
+{
+	struct trace_fprobe *tf = to_trace_fprobe(ev);
+
+	return trace_probe_is_enabled(&tf->tp);
+}
+
+static bool trace_fprobe_match_command_head(struct trace_fprobe *tf,
+					    int argc, const char **argv)
+{
+	char buf[MAX_ARGSTR_LEN + 1];
+
+	if (!argc)
+		return true;
+
+	snprintf(buf, sizeof(buf), "%s", trace_fprobe_symbol(tf));
+	if (strcmp(buf, argv[0]))
+		return false;
+	argc--; argv++;
+
+	return trace_probe_match_command_args(&tf->tp, argc, argv);
+}
+
+static bool trace_fprobe_match(const char *system, const char *event,
+			int argc, const char **argv, struct dyn_event *ev)
+{
+	struct trace_fprobe *tf = to_trace_fprobe(ev);
+
+	if (event[0] != '\0' && strcmp(trace_probe_name(&tf->tp), event))
+		return false;
+
+	if (system && strcmp(trace_probe_group_name(&tf->tp), system))
+		return false;
+
+	return trace_fprobe_match_command_head(tf, argc, argv);
+}
+
+static bool trace_fprobe_is_registered(struct trace_fprobe *tf)
+{
+	return fprobe_is_registered(&tf->fp);
+}
+
+/*
+ * Note that we don't verify the fetch_insn code, since it does not come
+ * from user space.
+ */
+static int
+process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
+		   void *base)
+{
+	struct pt_regs *regs = rec;
+	unsigned long val;
+	int ret;
+
+retry:
+	/* 1st stage: get value from context */
+	switch (code->op) {
+	case FETCH_OP_STACK:
+		val = regs_get_kernel_stack_nth(regs, code->param);
+		break;
+	case FETCH_OP_STACKP:
+		val = kernel_stack_pointer(regs);
+		break;
+	case FETCH_OP_RETVAL:
+		val = regs_return_value(regs);
+		break;
+#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+	case FETCH_OP_ARG:
+		val = regs_get_kernel_argument(regs, code->param);
+		break;
+#endif
+	case FETCH_NOP_SYMBOL:	/* Ignore a place holder */
+		code++;
+		goto retry;
+	default:
+		ret = process_common_fetch_insn(code, &val);
+		if (ret < 0)
+			return ret;
+	}
+	code++;
+
+	return process_fetch_insn_bottom(code, val, dest, base);
+}
+NOKPROBE_SYMBOL(process_fetch_insn)
+
+/* function entry handler */
+static nokprobe_inline void
+__fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip,
+		    struct pt_regs *regs,
+		    struct trace_event_file *trace_file)
+{
+	struct fentry_trace_entry_head *entry;
+	struct trace_event_call *call = trace_probe_event_call(&tf->tp);
+	struct trace_event_buffer fbuffer;
+	int dsize;
+
+	if (WARN_ON_ONCE(call != trace_file->event_call))
+		return;
+
+	if (trace_trigger_soft_disabled(trace_file))
+		return;
+
+	dsize = __get_data_size(&tf->tp, regs);
+
+	entry = trace_event_buffer_reserve(&fbuffer, trace_file,
+					   sizeof(*entry) + tf->tp.size + dsize);
+	if (!entry)
+		return;
+
+	fbuffer.regs = regs;
+	entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
+	entry->ip = entry_ip;
+	store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize);
+
+	trace_event_buffer_commit(&fbuffer);
+}
+
+static void
+fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip,
+		  struct pt_regs *regs)
+{
+	struct event_file_link *link;
+
+	trace_probe_for_each_link_rcu(link, &tf->tp)
+		__fentry_trace_func(tf, entry_ip, regs, link->file);
+}
+NOKPROBE_SYMBOL(fentry_trace_func);
+
+/* Kretprobe handler */
+static nokprobe_inline void
+__fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip,
+		   unsigned long ret_ip, struct pt_regs *regs,
+		   struct trace_event_file *trace_file)
+{
+	struct fexit_trace_entry_head *entry;
+	struct trace_event_buffer fbuffer;
+	struct trace_event_call *call = trace_probe_event_call(&tf->tp);
+	int dsize;
+
+	if (WARN_ON_ONCE(call != trace_file->event_call))
+		return;
+
+	if (trace_trigger_soft_disabled(trace_file))
+		return;
+
+	dsize = __get_data_size(&tf->tp, regs);
+
+	entry = trace_event_buffer_reserve(&fbuffer, trace_file,
+					   sizeof(*entry) + tf->tp.size + dsize);
+	if (!entry)
+		return;
+
+	fbuffer.regs = regs;
+	entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
+	entry->func = entry_ip;
+	entry->ret_ip = ret_ip;
+	store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize);
+
+	trace_event_buffer_commit(&fbuffer);
+}
+
+static void
+fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip,
+		 unsigned long ret_ip, struct pt_regs *regs)
+{
+	struct event_file_link *link;
+
+	trace_probe_for_each_link_rcu(link, &tf->tp)
+		__fexit_trace_func(tf, entry_ip, ret_ip, regs, link->file);
+}
+NOKPROBE_SYMBOL(fexit_trace_func);
+
+#ifdef CONFIG_PERF_EVENTS
+
+static int fentry_perf_func(struct trace_fprobe *tf, unsigned long entry_ip,
+			    struct pt_regs *regs)
+{
+	struct trace_event_call *call = trace_probe_event_call(&tf->tp);
+	struct fentry_trace_entry_head *entry;
+	struct hlist_head *head;
+	int size, __size, dsize;
+	int rctx;
+
+	head = this_cpu_ptr(call->perf_events);
+	if (hlist_empty(head))
+		return 0;
+
+	dsize = __get_data_size(&tf->tp, regs);
+	__size = sizeof(*entry) + tf->tp.size + dsize;
+	size = ALIGN(__size + sizeof(u32), sizeof(u64));
+	size -= sizeof(u32);
+
+	entry = perf_trace_buf_alloc(size, NULL, &rctx);
+	if (!entry)
+		return 0;
+
+	entry->ip = entry_ip;
+	memset(&entry[1], 0, dsize);
+	store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize);
+	perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
+			      head, NULL);
+	return 0;
+}
+NOKPROBE_SYMBOL(fentry_perf_func);
+
+static void
+fexit_perf_func(struct trace_fprobe *tf, unsigned long entry_ip,
+		unsigned long ret_ip, struct pt_regs *regs)
+{
+	struct trace_event_call *call = trace_probe_event_call(&tf->tp);
+	struct fexit_trace_entry_head *entry;
+	struct hlist_head *head;
+	int size, __size, dsize;
+	int rctx;
+
+	head = this_cpu_ptr(call->perf_events);
+	if (hlist_empty(head))
+		return;
+
+	dsize = __get_data_size(&tf->tp, regs);
+	__size = sizeof(*entry) + tf->tp.size + dsize;
+	size = ALIGN(__size + sizeof(u32), sizeof(u64));
+	size -= sizeof(u32);
+
+	entry = perf_trace_buf_alloc(size, NULL, &rctx);
+	if (!entry)
+		return;
+
+	entry->func = entry_ip;
+	entry->ret_ip = ret_ip;
+	store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize);
+	perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
+			      head, NULL);
+}
+NOKPROBE_SYMBOL(fexit_perf_func);
+#endif	/* CONFIG_PERF_EVENTS */
+
+static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip,
+			     unsigned long ret_ip, struct pt_regs *regs,
+			     void *entry_data)
+{
+	struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp);
+	int ret = 0;
+
+	if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE))
+		fentry_trace_func(tf, entry_ip, regs);
+#ifdef CONFIG_PERF_EVENTS
+	if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE))
+		ret = fentry_perf_func(tf, entry_ip, regs);
+#endif
+	return ret;
+}
+NOKPROBE_SYMBOL(fentry_dispatcher);
+
+static void fexit_dispatcher(struct fprobe *fp, unsigned long entry_ip,
+			     unsigned long ret_ip, struct pt_regs *regs,
+			     void *entry_data)
+{
+	struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp);
+
+	if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE))
+		fexit_trace_func(tf, entry_ip, ret_ip, regs);
+#ifdef CONFIG_PERF_EVENTS
+	if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE))
+		fexit_perf_func(tf, entry_ip, ret_ip, regs);
+#endif
+}
+NOKPROBE_SYMBOL(fexit_dispatcher);
+
+static void free_trace_fprobe(struct trace_fprobe *tf)
+{
+	if (tf) {
+		trace_probe_cleanup(&tf->tp);
+		kfree(tf->symbol);
+		kfree(tf);
+	}
+}
+
+/*
+ * Allocate new trace_probe and initialize it (including fprobe).
+ */
+static struct trace_fprobe *alloc_trace_fprobe(const char *group,
+					       const char *event,
+					       const char *symbol,
+					       struct tracepoint *tpoint,
+					       int maxactive,
+					       int nargs, bool is_return)
+{
+	struct trace_fprobe *tf;
+	int ret = -ENOMEM;
+
+	tf = kzalloc(struct_size(tf, tp.args, nargs), GFP_KERNEL);
+	if (!tf)
+		return ERR_PTR(ret);
+
+	tf->symbol = kstrdup(symbol, GFP_KERNEL);
+	if (!tf->symbol)
+		goto error;
+
+	if (is_return)
+		tf->fp.exit_handler = fexit_dispatcher;
+	else
+		tf->fp.entry_handler = fentry_dispatcher;
+
+	tf->tpoint = tpoint;
+	tf->fp.nr_maxactive = maxactive;
+
+	ret = trace_probe_init(&tf->tp, event, group, false);
+	if (ret < 0)
+		goto error;
+
+	dyn_event_init(&tf->devent, &trace_fprobe_ops);
+	return tf;
+error:
+	free_trace_fprobe(tf);
+	return ERR_PTR(ret);
+}
+
+static struct trace_fprobe *find_trace_fprobe(const char *event,
+					      const char *group)
+{
+	struct dyn_event *pos;
+	struct trace_fprobe *tf;
+
+	for_each_trace_fprobe(tf, pos)
+		if (strcmp(trace_probe_name(&tf->tp), event) == 0 &&
+		    strcmp(trace_probe_group_name(&tf->tp), group) == 0)
+			return tf;
+	return NULL;
+}
+
+static inline int __enable_trace_fprobe(struct trace_fprobe *tf)
+{
+	if (trace_fprobe_is_registered(tf))
+		enable_fprobe(&tf->fp);
+
+	return 0;
+}
+
+static void __disable_trace_fprobe(struct trace_probe *tp)
+{
+	struct trace_fprobe *tf;
+
+	list_for_each_entry(tf, trace_probe_probe_list(tp), tp.list) {
+		if (!trace_fprobe_is_registered(tf))
+			continue;
+		disable_fprobe(&tf->fp);
+	}
+}
+
+/*
+ * Enable trace_probe
+ * if the file is NULL, enable "perf" handler, or enable "trace" handler.
+ */
+static int enable_trace_fprobe(struct trace_event_call *call,
+			       struct trace_event_file *file)
+{
+	struct trace_probe *tp;
+	struct trace_fprobe *tf;
+	bool enabled;
+	int ret = 0;
+
+	tp = trace_probe_primary_from_call(call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENODEV;
+	enabled = trace_probe_is_enabled(tp);
+
+	/* This also changes "enabled" state */
+	if (file) {
+		ret = trace_probe_add_file(tp, file);
+		if (ret)
+			return ret;
+	} else
+		trace_probe_set_flag(tp, TP_FLAG_PROFILE);
+
+	if (!enabled) {
+		list_for_each_entry(tf, trace_probe_probe_list(tp), tp.list) {
+			/* TODO: check the fprobe is gone */
+			__enable_trace_fprobe(tf);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Disable trace_probe
+ * if the file is NULL, disable "perf" handler, or disable "trace" handler.
+ */
+static int disable_trace_fprobe(struct trace_event_call *call,
+				struct trace_event_file *file)
+{
+	struct trace_probe *tp;
+
+	tp = trace_probe_primary_from_call(call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENODEV;
+
+	if (file) {
+		if (!trace_probe_get_file_link(tp, file))
+			return -ENOENT;
+		if (!trace_probe_has_single_file(tp))
+			goto out;
+		trace_probe_clear_flag(tp, TP_FLAG_TRACE);
+	} else
+		trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
+
+	if (!trace_probe_is_enabled(tp))
+		__disable_trace_fprobe(tp);
+
+ out:
+	if (file)
+		/*
+		 * Synchronization is done in below function. For perf event,
+		 * file == NULL and perf_trace_event_unreg() calls
+		 * tracepoint_synchronize_unregister() to ensure synchronize
+		 * event. We don't need to care about it.
+		 */
+		trace_probe_remove_file(tp, file);
+
+	return 0;
+}
+
+/* Event entry printers */
+static enum print_line_t
+print_fentry_event(struct trace_iterator *iter, int flags,
+		   struct trace_event *event)
+{
+	struct fentry_trace_entry_head *field;
+	struct trace_seq *s = &iter->seq;
+	struct trace_probe *tp;
+
+	field = (struct fentry_trace_entry_head *)iter->ent;
+	tp = trace_probe_primary_from_call(
+		container_of(event, struct trace_event_call, event));
+	if (WARN_ON_ONCE(!tp))
+		goto out;
+
+	trace_seq_printf(s, "%s: (", trace_probe_name(tp));
+
+	if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
+		goto out;
+
+	trace_seq_putc(s, ')');
+
+	if (trace_probe_print_args(s, tp->args, tp->nr_args,
+			     (u8 *)&field[1], field) < 0)
+		goto out;
+
+	trace_seq_putc(s, '\n');
+ out:
+	return trace_handle_return(s);
+}
+
+static enum print_line_t
+print_fexit_event(struct trace_iterator *iter, int flags,
+		  struct trace_event *event)
+{
+	struct fexit_trace_entry_head *field;
+	struct trace_seq *s = &iter->seq;
+	struct trace_probe *tp;
+
+	field = (struct fexit_trace_entry_head *)iter->ent;
+	tp = trace_probe_primary_from_call(
+		container_of(event, struct trace_event_call, event));
+	if (WARN_ON_ONCE(!tp))
+		goto out;
+
+	trace_seq_printf(s, "%s: (", trace_probe_name(tp));
+
+	if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
+		goto out;
+
+	trace_seq_puts(s, " <- ");
+
+	if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
+		goto out;
+
+	trace_seq_putc(s, ')');
+
+	if (trace_probe_print_args(s, tp->args, tp->nr_args,
+			     (u8 *)&field[1], field) < 0)
+		goto out;
+
+	trace_seq_putc(s, '\n');
+
+ out:
+	return trace_handle_return(s);
+}
+
+static int fentry_event_define_fields(struct trace_event_call *event_call)
+{
+	int ret;
+	struct fentry_trace_entry_head field;
+	struct trace_probe *tp;
+
+	tp = trace_probe_primary_from_call(event_call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENOENT;
+
+	DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
+
+	return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
+}
+
+static int fexit_event_define_fields(struct trace_event_call *event_call)
+{
+	int ret;
+	struct fexit_trace_entry_head field;
+	struct trace_probe *tp;
+
+	tp = trace_probe_primary_from_call(event_call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENOENT;
+
+	DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
+	DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
+
+	return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
+}
+
+static struct trace_event_functions fentry_funcs = {
+	.trace		= print_fentry_event
+};
+
+static struct trace_event_functions fexit_funcs = {
+	.trace		= print_fexit_event
+};
+
+static struct trace_event_fields fentry_fields_array[] = {
+	{ .type = TRACE_FUNCTION_TYPE,
+	  .define_fields = fentry_event_define_fields },
+	{}
+};
+
+static struct trace_event_fields fexit_fields_array[] = {
+	{ .type = TRACE_FUNCTION_TYPE,
+	  .define_fields = fexit_event_define_fields },
+	{}
+};
+
+static int fprobe_register(struct trace_event_call *event,
+			   enum trace_reg type, void *data);
+
+static inline void init_trace_event_call(struct trace_fprobe *tf)
+{
+	struct trace_event_call *call = trace_probe_event_call(&tf->tp);
+
+	if (trace_fprobe_is_return(tf)) {
+		call->event.funcs = &fexit_funcs;
+		call->class->fields_array = fexit_fields_array;
+	} else {
+		call->event.funcs = &fentry_funcs;
+		call->class->fields_array = fentry_fields_array;
+	}
+
+	call->flags = TRACE_EVENT_FL_FPROBE;
+	call->class->reg = fprobe_register;
+}
+
+static int register_fprobe_event(struct trace_fprobe *tf)
+{
+	init_trace_event_call(tf);
+
+	return trace_probe_register_event_call(&tf->tp);
+}
+
+static int unregister_fprobe_event(struct trace_fprobe *tf)
+{
+	return trace_probe_unregister_event_call(&tf->tp);
+}
+
+/* Internal register function - just handle fprobe and flags */
+static int __register_trace_fprobe(struct trace_fprobe *tf)
+{
+	int i, ret;
+
+	/* Should we need new LOCKDOWN flag for fprobe? */
+	ret = security_locked_down(LOCKDOWN_KPROBES);
+	if (ret)
+		return ret;
+
+	if (trace_fprobe_is_registered(tf))
+		return -EINVAL;
+
+	for (i = 0; i < tf->tp.nr_args; i++) {
+		ret = traceprobe_update_arg(&tf->tp.args[i]);
+		if (ret)
+			return ret;
+	}
+
+	/* Set/clear disabled flag according to tp->flag */
+	if (trace_probe_is_enabled(&tf->tp))
+		tf->fp.flags &= ~FPROBE_FL_DISABLED;
+	else
+		tf->fp.flags |= FPROBE_FL_DISABLED;
+
+	if (trace_fprobe_is_tracepoint(tf)) {
+		struct tracepoint *tpoint = tf->tpoint;
+		unsigned long ip = (unsigned long)tpoint->probestub;
+		/*
+		 * Here, we do 2 steps to enable fprobe on a tracepoint.
+		 * At first, put __probestub_##TP function on the tracepoint
+		 * and put a fprobe on the stub function.
+		 */
+		ret = tracepoint_probe_register_prio_may_exist(tpoint,
+					tpoint->probestub, NULL, 0);
+		if (ret < 0)
+			return ret;
+		return register_fprobe_ips(&tf->fp, &ip, 1);
+	}
+
+	/* TODO: handle filter, nofilter or symbol list */
+	return register_fprobe(&tf->fp, tf->symbol, NULL);
+}
+
+/* Internal unregister function - just handle fprobe and flags */
+static void __unregister_trace_fprobe(struct trace_fprobe *tf)
+{
+	if (trace_fprobe_is_registered(tf)) {
+		unregister_fprobe(&tf->fp);
+		memset(&tf->fp, 0, sizeof(tf->fp));
+		if (trace_fprobe_is_tracepoint(tf)) {
+			tracepoint_probe_unregister(tf->tpoint,
+					tf->tpoint->probestub, NULL);
+			tf->tpoint = NULL;
+			tf->mod = NULL;
+		}
+	}
+}
+
+/* TODO: make this trace_*probe common function */
+/* Unregister a trace_probe and probe_event */
+static int unregister_trace_fprobe(struct trace_fprobe *tf)
+{
+	/* If other probes are on the event, just unregister fprobe */
+	if (trace_probe_has_sibling(&tf->tp))
+		goto unreg;
+
+	/* Enabled event can not be unregistered */
+	if (trace_probe_is_enabled(&tf->tp))
+		return -EBUSY;
+
+	/* If there's a reference to the dynamic event */
+	if (trace_event_dyn_busy(trace_probe_event_call(&tf->tp)))
+		return -EBUSY;
+
+	/* Will fail if probe is being used by ftrace or perf */
+	if (unregister_fprobe_event(tf))
+		return -EBUSY;
+
+unreg:
+	__unregister_trace_fprobe(tf);
+	dyn_event_remove(&tf->devent);
+	trace_probe_unlink(&tf->tp);
+
+	return 0;
+}
+
+static bool trace_fprobe_has_same_fprobe(struct trace_fprobe *orig,
+					 struct trace_fprobe *comp)
+{
+	struct trace_probe_event *tpe = orig->tp.event;
+	int i;
+
+	list_for_each_entry(orig, &tpe->probes, tp.list) {
+		if (strcmp(trace_fprobe_symbol(orig),
+			   trace_fprobe_symbol(comp)))
+			continue;
+
+		/*
+		 * trace_probe_compare_arg_type() ensured that nr_args and
+		 * each argument name and type are same. Let's compare comm.
+		 */
+		for (i = 0; i < orig->tp.nr_args; i++) {
+			if (strcmp(orig->tp.args[i].comm,
+				   comp->tp.args[i].comm))
+				break;
+		}
+
+		if (i == orig->tp.nr_args)
+			return true;
+	}
+
+	return false;
+}
+
+static int append_trace_fprobe(struct trace_fprobe *tf, struct trace_fprobe *to)
+{
+	int ret;
+
+	if (trace_fprobe_is_return(tf) != trace_fprobe_is_return(to) ||
+	    trace_fprobe_is_tracepoint(tf) != trace_fprobe_is_tracepoint(to)) {
+		trace_probe_log_set_index(0);
+		trace_probe_log_err(0, DIFF_PROBE_TYPE);
+		return -EEXIST;
+	}
+	ret = trace_probe_compare_arg_type(&tf->tp, &to->tp);
+	if (ret) {
+		/* Note that argument starts index = 2 */
+		trace_probe_log_set_index(ret + 1);
+		trace_probe_log_err(0, DIFF_ARG_TYPE);
+		return -EEXIST;
+	}
+	if (trace_fprobe_has_same_fprobe(to, tf)) {
+		trace_probe_log_set_index(0);
+		trace_probe_log_err(0, SAME_PROBE);
+		return -EEXIST;
+	}
+
+	/* Append to existing event */
+	ret = trace_probe_append(&tf->tp, &to->tp);
+	if (ret)
+		return ret;
+
+	ret = __register_trace_fprobe(tf);
+	if (ret)
+		trace_probe_unlink(&tf->tp);
+	else
+		dyn_event_add(&tf->devent, trace_probe_event_call(&tf->tp));
+
+	return ret;
+}
+
+/* Register a trace_probe and probe_event */
+static int register_trace_fprobe(struct trace_fprobe *tf)
+{
+	struct trace_fprobe *old_tf;
+	int ret;
+
+	mutex_lock(&event_mutex);
+
+	old_tf = find_trace_fprobe(trace_probe_name(&tf->tp),
+				   trace_probe_group_name(&tf->tp));
+	if (old_tf) {
+		ret = append_trace_fprobe(tf, old_tf);
+		goto end;
+	}
+
+	/* Register new event */
+	ret = register_fprobe_event(tf);
+	if (ret) {
+		if (ret == -EEXIST) {
+			trace_probe_log_set_index(0);
+			trace_probe_log_err(0, EVENT_EXIST);
+		} else
+			pr_warn("Failed to register probe event(%d)\n", ret);
+		goto end;
+	}
+
+	/* Register fprobe */
+	ret = __register_trace_fprobe(tf);
+	if (ret < 0)
+		unregister_fprobe_event(tf);
+	else
+		dyn_event_add(&tf->devent, trace_probe_event_call(&tf->tp));
+
+end:
+	mutex_unlock(&event_mutex);
+	return ret;
+}
+
+#ifdef CONFIG_MODULES
+static int __tracepoint_probe_module_cb(struct notifier_block *self,
+					unsigned long val, void *data)
+{
+	struct tp_module *tp_mod = data;
+	struct trace_fprobe *tf;
+	struct dyn_event *pos;
+
+	if (val != MODULE_STATE_GOING)
+		return NOTIFY_DONE;
+
+	mutex_lock(&event_mutex);
+	for_each_trace_fprobe(tf, pos) {
+		if (tp_mod->mod == tf->mod) {
+			tracepoint_probe_unregister(tf->tpoint,
+					tf->tpoint->probestub, NULL);
+			tf->tpoint = NULL;
+			tf->mod = NULL;
+		}
+	}
+	mutex_unlock(&event_mutex);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block tracepoint_module_nb = {
+	.notifier_call = __tracepoint_probe_module_cb,
+};
+#endif /* CONFIG_MODULES */
+
+struct __find_tracepoint_cb_data {
+	const char *tp_name;
+	struct tracepoint *tpoint;
+};
+
+static void __find_tracepoint_cb(struct tracepoint *tp, void *priv)
+{
+	struct __find_tracepoint_cb_data *data = priv;
+
+	if (!data->tpoint && !strcmp(data->tp_name, tp->name))
+		data->tpoint = tp;
+}
+
+static struct tracepoint *find_tracepoint(const char *tp_name)
+{
+	struct __find_tracepoint_cb_data data = {
+		.tp_name = tp_name,
+	};
+
+	for_each_kernel_tracepoint(__find_tracepoint_cb, &data);
+
+	return data.tpoint;
+}
+
+static int __trace_fprobe_create(int argc, const char *argv[])
+{
+	/*
+	 * Argument syntax:
+	 *  - Add fentry probe:
+	 *      f[:[GRP/][EVENT]] [MOD:]KSYM [FETCHARGS]
+	 *  - Add fexit probe:
+	 *      f[N][:[GRP/][EVENT]] [MOD:]KSYM%return [FETCHARGS]
+	 *  - Add tracepoint probe:
+	 *      t[:[GRP/][EVENT]] TRACEPOINT [FETCHARGS]
+	 *
+	 * Fetch args:
+	 *  $retval	: fetch return value
+	 *  $stack	: fetch stack address
+	 *  $stackN	: fetch Nth entry of stack (N:0-)
+	 *  $argN	: fetch Nth argument (N:1-)
+	 *  $comm       : fetch current task comm
+	 *  @ADDR	: fetch memory at ADDR (ADDR should be in kernel)
+	 *  @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
+	 * Dereferencing memory fetch:
+	 *  +|-offs(ARG) : fetch memory at ARG +|- offs address.
+	 * Alias name of args:
+	 *  NAME=FETCHARG : set NAME as alias of FETCHARG.
+	 * Type of args:
+	 *  FETCHARG:TYPE : use TYPE instead of unsigned long.
+	 */
+	struct trace_fprobe *tf = NULL;
+	int i, len, new_argc = 0, ret = 0;
+	bool is_return = false;
+	char *symbol = NULL, *tmp = NULL;
+	const char *event = NULL, *group = FPROBE_EVENT_SYSTEM;
+	const char **new_argv = NULL;
+	int maxactive = 0;
+	char buf[MAX_EVENT_NAME_LEN];
+	char gbuf[MAX_EVENT_NAME_LEN];
+	char sbuf[KSYM_NAME_LEN];
+	char abuf[MAX_BTF_ARGS_LEN];
+	bool is_tracepoint = false;
+	struct tracepoint *tpoint = NULL;
+	struct traceprobe_parse_context ctx = {
+		.flags = TPARG_FL_KERNEL | TPARG_FL_FPROBE,
+	};
+
+	if ((argv[0][0] != 'f' && argv[0][0] != 't') || argc < 2)
+		return -ECANCELED;
+
+	if (argv[0][0] == 't') {
+		is_tracepoint = true;
+		group = TRACEPOINT_EVENT_SYSTEM;
+	}
+
+	trace_probe_log_init("trace_fprobe", argc, argv);
+
+	event = strchr(&argv[0][1], ':');
+	if (event)
+		event++;
+
+	if (isdigit(argv[0][1])) {
+		if (event)
+			len = event - &argv[0][1] - 1;
+		else
+			len = strlen(&argv[0][1]);
+		if (len > MAX_EVENT_NAME_LEN - 1) {
+			trace_probe_log_err(1, BAD_MAXACT);
+			goto parse_error;
+		}
+		memcpy(buf, &argv[0][1], len);
+		buf[len] = '\0';
+		ret = kstrtouint(buf, 0, &maxactive);
+		if (ret || !maxactive) {
+			trace_probe_log_err(1, BAD_MAXACT);
+			goto parse_error;
+		}
+		/* fprobe rethook instances are iterated over via a list. The
+		 * maximum should stay reasonable.
+		 */
+		if (maxactive > RETHOOK_MAXACTIVE_MAX) {
+			trace_probe_log_err(1, MAXACT_TOO_BIG);
+			goto parse_error;
+		}
+	}
+
+	trace_probe_log_set_index(1);
+
+	/* a symbol(or tracepoint) must be specified */
+	symbol = kstrdup(argv[1], GFP_KERNEL);
+	if (!symbol)
+		return -ENOMEM;
+
+	tmp = strchr(symbol, '%');
+	if (tmp) {
+		if (!is_tracepoint && !strcmp(tmp, "%return")) {
+			*tmp = '\0';
+			is_return = true;
+		} else {
+			trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX);
+			goto parse_error;
+		}
+	}
+	if (!is_return && maxactive) {
+		trace_probe_log_set_index(0);
+		trace_probe_log_err(1, BAD_MAXACT_TYPE);
+		goto parse_error;
+	}
+
+	trace_probe_log_set_index(0);
+	if (event) {
+		ret = traceprobe_parse_event_name(&event, &group, gbuf,
+						  event - argv[0]);
+		if (ret)
+			goto parse_error;
+	}
+
+	if (!event) {
+		/* Make a new event name */
+		if (is_tracepoint)
+			snprintf(buf, MAX_EVENT_NAME_LEN, "%s%s",
+				 isdigit(*symbol) ? "_" : "", symbol);
+		else
+			snprintf(buf, MAX_EVENT_NAME_LEN, "%s__%s", symbol,
+				 is_return ? "exit" : "entry");
+		sanitize_event_name(buf);
+		event = buf;
+	}
+
+	if (is_return)
+		ctx.flags |= TPARG_FL_RETURN;
+	else
+		ctx.flags |= TPARG_FL_FENTRY;
+
+	if (is_tracepoint) {
+		ctx.flags |= TPARG_FL_TPOINT;
+		tpoint = find_tracepoint(symbol);
+		if (!tpoint) {
+			trace_probe_log_set_index(1);
+			trace_probe_log_err(0, NO_TRACEPOINT);
+			goto parse_error;
+		}
+		ctx.funcname = kallsyms_lookup(
+				(unsigned long)tpoint->probestub,
+				NULL, NULL, NULL, sbuf);
+	} else
+		ctx.funcname = symbol;
+
+	argc -= 2; argv += 2;
+	new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc,
+					       abuf, MAX_BTF_ARGS_LEN, &ctx);
+	if (IS_ERR(new_argv)) {
+		ret = PTR_ERR(new_argv);
+		new_argv = NULL;
+		goto out;
+	}
+	if (new_argv) {
+		argc = new_argc;
+		argv = new_argv;
+	}
+
+	/* setup a probe */
+	tf = alloc_trace_fprobe(group, event, symbol, tpoint, maxactive,
+				argc, is_return);
+	if (IS_ERR(tf)) {
+		ret = PTR_ERR(tf);
+		/* This must return -ENOMEM, else there is a bug */
+		WARN_ON_ONCE(ret != -ENOMEM);
+		goto out;	/* We know tf is not allocated */
+	}
+
+	if (is_tracepoint)
+		tf->mod = __module_text_address(
+				(unsigned long)tf->tpoint->probestub);
+
+	/* parse arguments */
+	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+		trace_probe_log_set_index(i + 2);
+		ctx.offset = 0;
+		ret = traceprobe_parse_probe_arg(&tf->tp, i, argv[i], &ctx);
+		if (ret)
+			goto error;	/* This can be -ENOMEM */
+	}
+
+	ret = traceprobe_set_print_fmt(&tf->tp,
+			is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL);
+	if (ret < 0)
+		goto error;
+
+	ret = register_trace_fprobe(tf);
+	if (ret) {
+		trace_probe_log_set_index(1);
+		if (ret == -EILSEQ)
+			trace_probe_log_err(0, BAD_INSN_BNDRY);
+		else if (ret == -ENOENT)
+			trace_probe_log_err(0, BAD_PROBE_ADDR);
+		else if (ret != -ENOMEM && ret != -EEXIST)
+			trace_probe_log_err(0, FAIL_REG_PROBE);
+		goto error;
+	}
+
+out:
+	trace_probe_log_clear();
+	kfree(new_argv);
+	kfree(symbol);
+	return ret;
+
+parse_error:
+	ret = -EINVAL;
+error:
+	free_trace_fprobe(tf);
+	goto out;
+}
+
+static int trace_fprobe_create(const char *raw_command)
+{
+	return trace_probe_create(raw_command, __trace_fprobe_create);
+}
+
+static int trace_fprobe_release(struct dyn_event *ev)
+{
+	struct trace_fprobe *tf = to_trace_fprobe(ev);
+	int ret = unregister_trace_fprobe(tf);
+
+	if (!ret)
+		free_trace_fprobe(tf);
+	return ret;
+}
+
+static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev)
+{
+	struct trace_fprobe *tf = to_trace_fprobe(ev);
+	int i;
+
+	if (trace_fprobe_is_tracepoint(tf))
+		seq_putc(m, 't');
+	else
+		seq_putc(m, 'f');
+	if (trace_fprobe_is_return(tf) && tf->fp.nr_maxactive)
+		seq_printf(m, "%d", tf->fp.nr_maxactive);
+	seq_printf(m, ":%s/%s", trace_probe_group_name(&tf->tp),
+				trace_probe_name(&tf->tp));
+
+	seq_printf(m, " %s%s", trace_fprobe_symbol(tf),
+			       trace_fprobe_is_return(tf) ? "%return" : "");
+
+	for (i = 0; i < tf->tp.nr_args; i++)
+		seq_printf(m, " %s=%s", tf->tp.args[i].name, tf->tp.args[i].comm);
+	seq_putc(m, '\n');
+
+	return 0;
+}
+
+/*
+ * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex.
+ */
+static int fprobe_register(struct trace_event_call *event,
+			   enum trace_reg type, void *data)
+{
+	struct trace_event_file *file = data;
+
+	switch (type) {
+	case TRACE_REG_REGISTER:
+		return enable_trace_fprobe(event, file);
+	case TRACE_REG_UNREGISTER:
+		return disable_trace_fprobe(event, file);
+
+#ifdef CONFIG_PERF_EVENTS
+	case TRACE_REG_PERF_REGISTER:
+		return enable_trace_fprobe(event, NULL);
+	case TRACE_REG_PERF_UNREGISTER:
+		return disable_trace_fprobe(event, NULL);
+	case TRACE_REG_PERF_OPEN:
+	case TRACE_REG_PERF_CLOSE:
+	case TRACE_REG_PERF_ADD:
+	case TRACE_REG_PERF_DEL:
+		return 0;
+#endif
+	}
+	return 0;
+}
+
+/*
+ * Register dynevent at core_initcall. This allows kernel to setup fprobe
+ * events in postcore_initcall without tracefs.
+ */
+static __init int init_fprobe_trace_early(void)
+{
+	int ret;
+
+	ret = dyn_event_register(&trace_fprobe_ops);
+	if (ret)
+		return ret;
+
+#ifdef CONFIG_MODULES
+	ret = register_tracepoint_module_notifier(&tracepoint_module_nb);
+	if (ret)
+		return ret;
+#endif
+
+	return 0;
+}
+core_initcall(init_fprobe_trace_early);
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 1b3fa7b854aa..23dba01831f7 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -732,9 +732,10 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 	 *  FETCHARG:TYPE : use TYPE instead of unsigned long.
 	 */
 	struct trace_kprobe *tk = NULL;
-	int i, len, ret = 0;
+	int i, len, new_argc = 0, ret = 0;
 	bool is_return = false;
 	char *symbol = NULL, *tmp = NULL;
+	const char **new_argv = NULL;
 	const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
 	enum probe_print_type ptype;
 	int maxactive = 0;
@@ -742,7 +743,8 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 	void *addr = NULL;
 	char buf[MAX_EVENT_NAME_LEN];
 	char gbuf[MAX_EVENT_NAME_LEN];
-	unsigned int flags = TPARG_FL_KERNEL;
+	char abuf[MAX_BTF_ARGS_LEN];
+	struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL };
 
 	switch (argv[0][0]) {
 	case 'r':
@@ -764,7 +766,7 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 
 	if (isdigit(argv[0][1])) {
 		if (!is_return) {
-			trace_probe_log_err(1, MAXACT_NO_KPROBE);
+			trace_probe_log_err(1, BAD_MAXACT_TYPE);
 			goto parse_error;
 		}
 		if (event)
@@ -823,10 +825,10 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 			goto parse_error;
 		}
 		if (is_return)
-			flags |= TPARG_FL_RETURN;
+			ctx.flags |= TPARG_FL_RETURN;
 		ret = kprobe_on_func_entry(NULL, symbol, offset);
-		if (ret == 0)
-			flags |= TPARG_FL_FENTRY;
+		if (ret == 0 && !is_return)
+			ctx.flags |= TPARG_FL_FENTRY;
 		/* Defer the ENOENT case until register kprobe */
 		if (ret == -EINVAL && is_return) {
 			trace_probe_log_err(0, BAD_RETPROBE);
@@ -854,21 +856,35 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 		event = buf;
 	}
 
+	argc -= 2; argv += 2;
+	ctx.funcname = symbol;
+	new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc,
+					       abuf, MAX_BTF_ARGS_LEN, &ctx);
+	if (IS_ERR(new_argv)) {
+		ret = PTR_ERR(new_argv);
+		new_argv = NULL;
+		goto out;
+	}
+	if (new_argv) {
+		argc = new_argc;
+		argv = new_argv;
+	}
+
 	/* setup a probe */
 	tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
-			       argc - 2, is_return);
+				argc, is_return);
 	if (IS_ERR(tk)) {
 		ret = PTR_ERR(tk);
 		/* This must return -ENOMEM, else there is a bug */
 		WARN_ON_ONCE(ret != -ENOMEM);
 		goto out;	/* We know tk is not allocated */
 	}
-	argc -= 2; argv += 2;
 
 	/* parse arguments */
 	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
 		trace_probe_log_set_index(i + 2);
-		ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], flags);
+		ctx.offset = 0;
+		ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx);
 		if (ret)
 			goto error;	/* This can be -ENOMEM */
 	}
@@ -892,6 +908,7 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 
 out:
 	trace_probe_log_clear();
+	kfree(new_argv);
 	kfree(symbol);
 	return ret;
 
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 73055ba8d8ef..7ba371da0926 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -11,6 +11,8 @@
  */
 #define pr_fmt(fmt)	"trace_probe: " fmt
 
+#include <linux/bpf.h>
+
 #include "trace_probe.h"
 
 #undef C
@@ -283,69 +285,354 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
 	return 0;
 }
 
+static int parse_trace_event_arg(char *arg, struct fetch_insn *code,
+				 struct traceprobe_parse_context *ctx)
+{
+	struct ftrace_event_field *field;
+	struct list_head *head;
+
+	head = trace_get_fields(ctx->event);
+	list_for_each_entry(field, head, link) {
+		if (!strcmp(arg, field->name)) {
+			code->op = FETCH_OP_TP_ARG;
+			code->data = field;
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
+
+static struct btf *traceprobe_get_btf(void)
+{
+	struct btf *btf = bpf_get_btf_vmlinux();
+
+	if (IS_ERR_OR_NULL(btf))
+		return NULL;
+
+	return btf;
+}
+
+static u32 btf_type_int(const struct btf_type *t)
+{
+	return *(u32 *)(t + 1);
+}
+
+static const char *type_from_btf_id(struct btf *btf, s32 id)
+{
+	const struct btf_type *t;
+	u32 intdata;
+	s32 tid;
+
+	/* TODO: const char * could be converted as a string */
+	t = btf_type_skip_modifiers(btf, id, &tid);
+
+	switch (BTF_INFO_KIND(t->info)) {
+	case BTF_KIND_ENUM:
+		/* enum is "int", so convert to "s32" */
+		return "s32";
+	case BTF_KIND_ENUM64:
+		return "s64";
+	case BTF_KIND_PTR:
+		/* pointer will be converted to "x??" */
+		if (IS_ENABLED(CONFIG_64BIT))
+			return "x64";
+		else
+			return "x32";
+	case BTF_KIND_INT:
+		intdata = btf_type_int(t);
+		if (BTF_INT_ENCODING(intdata) & BTF_INT_SIGNED) {
+			switch (BTF_INT_BITS(intdata)) {
+			case 8:
+				return "s8";
+			case 16:
+				return "s16";
+			case 32:
+				return "s32";
+			case 64:
+				return "s64";
+			}
+		} else {	/* unsigned */
+			switch (BTF_INT_BITS(intdata)) {
+			case 8:
+				return "u8";
+			case 16:
+				return "u16";
+			case 32:
+				return "u32";
+			case 64:
+				return "u64";
+			}
+		}
+	}
+	/* TODO: support other types */
+
+	return NULL;
+}
+
+static const struct btf_type *find_btf_func_proto(const char *funcname)
+{
+	struct btf *btf = traceprobe_get_btf();
+	const struct btf_type *t;
+	s32 id;
+
+	if (!btf || !funcname)
+		return ERR_PTR(-EINVAL);
+
+	id = btf_find_by_name_kind(btf, funcname, BTF_KIND_FUNC);
+	if (id <= 0)
+		return ERR_PTR(-ENOENT);
+
+	/* Get BTF_KIND_FUNC type */
+	t = btf_type_by_id(btf, id);
+	if (!btf_type_is_func(t))
+		return ERR_PTR(-ENOENT);
+
+	/* The type of BTF_KIND_FUNC is BTF_KIND_FUNC_PROTO */
+	t = btf_type_by_id(btf, t->type);
+	if (!btf_type_is_func_proto(t))
+		return ERR_PTR(-ENOENT);
+
+	return t;
+}
+
+static const struct btf_param *find_btf_func_param(const char *funcname, s32 *nr,
+						   bool tracepoint)
+{
+	const struct btf_param *param;
+	const struct btf_type *t;
+
+	if (!funcname || !nr)
+		return ERR_PTR(-EINVAL);
+
+	t = find_btf_func_proto(funcname);
+	if (IS_ERR(t))
+		return (const struct btf_param *)t;
+
+	*nr = btf_type_vlen(t);
+	param = (const struct btf_param *)(t + 1);
+
+	/* Hide the first 'data' argument of tracepoint */
+	if (tracepoint) {
+		(*nr)--;
+		param++;
+	}
+
+	if (*nr > 0)
+		return param;
+	else
+		return NULL;
+}
+
+static int parse_btf_arg(const char *varname, struct fetch_insn *code,
+			 struct traceprobe_parse_context *ctx)
+{
+	struct btf *btf = traceprobe_get_btf();
+	const struct btf_param *params;
+	int i;
+
+	if (!btf) {
+		trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
+		return -EOPNOTSUPP;
+	}
+
+	if (WARN_ON_ONCE(!ctx->funcname))
+		return -EINVAL;
+
+	if (!ctx->params) {
+		params = find_btf_func_param(ctx->funcname, &ctx->nr_params,
+					     ctx->flags & TPARG_FL_TPOINT);
+		if (IS_ERR(params)) {
+			trace_probe_log_err(ctx->offset, NO_BTF_ENTRY);
+			return PTR_ERR(params);
+		}
+		ctx->params = params;
+	} else
+		params = ctx->params;
+
+	for (i = 0; i < ctx->nr_params; i++) {
+		const char *name = btf_name_by_offset(btf, params[i].name_off);
+
+		if (name && !strcmp(name, varname)) {
+			code->op = FETCH_OP_ARG;
+			if (ctx->flags & TPARG_FL_TPOINT)
+				code->param = i + 1;
+			else
+				code->param = i;
+			return 0;
+		}
+	}
+	trace_probe_log_err(ctx->offset, NO_BTFARG);
+	return -ENOENT;
+}
+
+static const struct fetch_type *parse_btf_arg_type(int arg_idx,
+					struct traceprobe_parse_context *ctx)
+{
+	struct btf *btf = traceprobe_get_btf();
+	const char *typestr = NULL;
+
+	if (btf && ctx->params) {
+		if (ctx->flags & TPARG_FL_TPOINT)
+			arg_idx--;
+		typestr = type_from_btf_id(btf, ctx->params[arg_idx].type);
+	}
+
+	return find_fetch_type(typestr, ctx->flags);
+}
+
+static const struct fetch_type *parse_btf_retval_type(
+					struct traceprobe_parse_context *ctx)
+{
+	struct btf *btf = traceprobe_get_btf();
+	const char *typestr = NULL;
+	const struct btf_type *t;
+
+	if (btf && ctx->funcname) {
+		t = find_btf_func_proto(ctx->funcname);
+		if (!IS_ERR(t))
+			typestr = type_from_btf_id(btf, t->type);
+	}
+
+	return find_fetch_type(typestr, ctx->flags);
+}
+
+static bool is_btf_retval_void(const char *funcname)
+{
+	const struct btf_type *t;
+
+	t = find_btf_func_proto(funcname);
+	if (IS_ERR(t))
+		return false;
+
+	return t->type == 0;
+}
+#else
+static struct btf *traceprobe_get_btf(void)
+{
+	return NULL;
+}
+
+static const struct btf_param *find_btf_func_param(const char *funcname, s32 *nr,
+						   bool tracepoint)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
+static int parse_btf_arg(const char *varname, struct fetch_insn *code,
+			 struct traceprobe_parse_context *ctx)
+{
+	trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
+	return -EOPNOTSUPP;
+}
+
+#define parse_btf_arg_type(idx, ctx)		\
+	find_fetch_type(NULL, ctx->flags)
+
+#define parse_btf_retval_type(ctx)		\
+	find_fetch_type(NULL, ctx->flags)
+
+#define is_btf_retval_void(funcname)	(false)
+
+#endif
+
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-			struct fetch_insn *code, unsigned int flags, int offs)
+			    struct fetch_insn *code,
+			    struct traceprobe_parse_context *ctx)
 {
 	unsigned long param;
+	int err = TP_ERR_BAD_VAR;
 	int ret = 0;
 	int len;
 
-	if (flags & TPARG_FL_TPOINT) {
+	if (ctx->flags & TPARG_FL_TEVENT) {
 		if (code->data)
 			return -EFAULT;
-		code->data = kstrdup(arg, GFP_KERNEL);
-		if (!code->data)
-			return -ENOMEM;
-		code->op = FETCH_OP_TP_ARG;
-	} else if (strcmp(arg, "retval") == 0) {
-		if (flags & TPARG_FL_RETURN) {
+		ret = parse_trace_event_arg(arg, code, ctx);
+		if (!ret)
+			return 0;
+		if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
+			code->op = FETCH_OP_COMM;
+			return 0;
+		}
+		/* backward compatibility */
+		ctx->offset = 0;
+		goto inval;
+	}
+
+	if (strcmp(arg, "retval") == 0) {
+		if (ctx->flags & TPARG_FL_RETURN) {
+			if ((ctx->flags & TPARG_FL_KERNEL) &&
+			    is_btf_retval_void(ctx->funcname)) {
+				err = TP_ERR_NO_RETVAL;
+				goto inval;
+			}
 			code->op = FETCH_OP_RETVAL;
-		} else {
-			trace_probe_log_err(offs, RETVAL_ON_PROBE);
-			ret = -EINVAL;
+			return 0;
 		}
-	} else if ((len = str_has_prefix(arg, "stack"))) {
+		err = TP_ERR_RETVAL_ON_PROBE;
+		goto inval;
+	}
+
+	len = str_has_prefix(arg, "stack");
+	if (len) {
+
 		if (arg[len] == '\0') {
 			code->op = FETCH_OP_STACKP;
-		} else if (isdigit(arg[len])) {
+			return 0;
+		}
+
+		if (isdigit(arg[len])) {
 			ret = kstrtoul(arg + len, 10, &param);
-			if (ret) {
-				goto inval_var;
-			} else if ((flags & TPARG_FL_KERNEL) &&
-				    param > PARAM_MAX_STACK) {
-				trace_probe_log_err(offs, BAD_STACK_NUM);
-				ret = -EINVAL;
-			} else {
-				code->op = FETCH_OP_STACK;
-				code->param = (unsigned int)param;
+			if (ret)
+				goto inval;
+
+			if ((ctx->flags & TPARG_FL_KERNEL) &&
+			    param > PARAM_MAX_STACK) {
+				err = TP_ERR_BAD_STACK_NUM;
+				goto inval;
 			}
-		} else
-			goto inval_var;
-	} else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
+			code->op = FETCH_OP_STACK;
+			code->param = (unsigned int)param;
+			return 0;
+		}
+		goto inval;
+	}
+
+	if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
 		code->op = FETCH_OP_COMM;
+		return 0;
+	}
+
 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
-	} else if (((flags & TPARG_FL_MASK) ==
-		    (TPARG_FL_KERNEL | TPARG_FL_FENTRY)) &&
-		   (len = str_has_prefix(arg, "arg"))) {
+	len = str_has_prefix(arg, "arg");
+	if (len && tparg_is_function_entry(ctx->flags)) {
 		ret = kstrtoul(arg + len, 10, &param);
-		if (ret) {
-			goto inval_var;
-		} else if (!param || param > PARAM_MAX_STACK) {
-			trace_probe_log_err(offs, BAD_ARG_NUM);
-			return -EINVAL;
+		if (ret)
+			goto inval;
+
+		if (!param || param > PARAM_MAX_STACK) {
+			err = TP_ERR_BAD_ARG_NUM;
+			goto inval;
 		}
+
 		code->op = FETCH_OP_ARG;
 		code->param = (unsigned int)param - 1;
+		/*
+		 * The tracepoint probe will probe a stub function, and the
+		 * first parameter of the stub is a dummy and should be ignored.
+		 */
+		if (ctx->flags & TPARG_FL_TPOINT)
+			code->param++;
+		return 0;
+	}
 #endif
-	} else
-		goto inval_var;
 
-	return ret;
-
-inval_var:
-	trace_probe_log_err(offs, BAD_VAR);
+inval:
+	__trace_probe_log_err(ctx->offset, err);
 	return -EINVAL;
 }
 
@@ -378,7 +665,7 @@ static int __parse_imm_string(char *str, char **pbuf, int offs)
 static int
 parse_probe_arg(char *arg, const struct fetch_type *type,
 		struct fetch_insn **pcode, struct fetch_insn *end,
-		unsigned int flags, int offs)
+		struct traceprobe_parse_context *ctx)
 {
 	struct fetch_insn *code = *pcode;
 	unsigned long param;
@@ -389,13 +676,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 
 	switch (arg[0]) {
 	case '$':
-		ret = parse_probe_vars(arg + 1, type, code, flags, offs);
+		ret = parse_probe_vars(arg + 1, type, code, ctx);
 		break;
 
 	case '%':	/* named register */
-		if (flags & TPARG_FL_TPOINT) {
-			/* eprobes do not handle registers */
-			trace_probe_log_err(offs, BAD_VAR);
+		if (ctx->flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) {
+			/* eprobe and fprobe do not handle registers */
+			trace_probe_log_err(ctx->offset, BAD_VAR);
 			break;
 		}
 		ret = regs_query_register_offset(arg + 1);
@@ -404,14 +691,14 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 			code->param = (unsigned int)ret;
 			ret = 0;
 		} else
-			trace_probe_log_err(offs, BAD_REG_NAME);
+			trace_probe_log_err(ctx->offset, BAD_REG_NAME);
 		break;
 
 	case '@':	/* memory, file-offset or symbol */
 		if (isdigit(arg[1])) {
 			ret = kstrtoul(arg + 1, 0, &param);
 			if (ret) {
-				trace_probe_log_err(offs, BAD_MEM_ADDR);
+				trace_probe_log_err(ctx->offset, BAD_MEM_ADDR);
 				break;
 			}
 			/* load address */
@@ -419,13 +706,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 			code->immediate = param;
 		} else if (arg[1] == '+') {
 			/* kprobes don't support file offsets */
-			if (flags & TPARG_FL_KERNEL) {
-				trace_probe_log_err(offs, FILE_ON_KPROBE);
+			if (ctx->flags & TPARG_FL_KERNEL) {
+				trace_probe_log_err(ctx->offset, FILE_ON_KPROBE);
 				return -EINVAL;
 			}
 			ret = kstrtol(arg + 2, 0, &offset);
 			if (ret) {
-				trace_probe_log_err(offs, BAD_FILE_OFFS);
+				trace_probe_log_err(ctx->offset, BAD_FILE_OFFS);
 				break;
 			}
 
@@ -433,8 +720,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 			code->immediate = (unsigned long)offset;  // imm64?
 		} else {
 			/* uprobes don't support symbols */
-			if (!(flags & TPARG_FL_KERNEL)) {
-				trace_probe_log_err(offs, SYM_ON_UPROBE);
+			if (!(ctx->flags & TPARG_FL_KERNEL)) {
+				trace_probe_log_err(ctx->offset, SYM_ON_UPROBE);
 				return -EINVAL;
 			}
 			/* Preserve symbol for updating */
@@ -443,7 +730,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 			if (!code->data)
 				return -ENOMEM;
 			if (++code == end) {
-				trace_probe_log_err(offs, TOO_MANY_OPS);
+				trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 				return -EINVAL;
 			}
 			code->op = FETCH_OP_IMM;
@@ -451,7 +738,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 		}
 		/* These are fetching from memory */
 		if (++code == end) {
-			trace_probe_log_err(offs, TOO_MANY_OPS);
+			trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 			return -EINVAL;
 		}
 		*pcode = code;
@@ -470,36 +757,38 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 			arg++;	/* Skip '+', because kstrtol() rejects it. */
 		tmp = strchr(arg, '(');
 		if (!tmp) {
-			trace_probe_log_err(offs, DEREF_NEED_BRACE);
+			trace_probe_log_err(ctx->offset, DEREF_NEED_BRACE);
 			return -EINVAL;
 		}
 		*tmp = '\0';
 		ret = kstrtol(arg, 0, &offset);
 		if (ret) {
-			trace_probe_log_err(offs, BAD_DEREF_OFFS);
+			trace_probe_log_err(ctx->offset, BAD_DEREF_OFFS);
 			break;
 		}
-		offs += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0);
+		ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0);
 		arg = tmp + 1;
 		tmp = strrchr(arg, ')');
 		if (!tmp) {
-			trace_probe_log_err(offs + strlen(arg),
+			trace_probe_log_err(ctx->offset + strlen(arg),
 					    DEREF_OPEN_BRACE);
 			return -EINVAL;
 		} else {
-			const struct fetch_type *t2 = find_fetch_type(NULL, flags);
+			const struct fetch_type *t2 = find_fetch_type(NULL, ctx->flags);
+			int cur_offs = ctx->offset;
 
 			*tmp = '\0';
-			ret = parse_probe_arg(arg, t2, &code, end, flags, offs);
+			ret = parse_probe_arg(arg, t2, &code, end, ctx);
 			if (ret)
 				break;
+			ctx->offset = cur_offs;
 			if (code->op == FETCH_OP_COMM ||
 			    code->op == FETCH_OP_DATA) {
-				trace_probe_log_err(offs, COMM_CANT_DEREF);
+				trace_probe_log_err(ctx->offset, COMM_CANT_DEREF);
 				return -EINVAL;
 			}
 			if (++code == end) {
-				trace_probe_log_err(offs, TOO_MANY_OPS);
+				trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 				return -EINVAL;
 			}
 			*pcode = code;
@@ -510,7 +799,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 		break;
 	case '\\':	/* Immediate value */
 		if (arg[1] == '"') {	/* Immediate string */
-			ret = __parse_imm_string(arg + 2, &tmp, offs + 2);
+			ret = __parse_imm_string(arg + 2, &tmp, ctx->offset + 2);
 			if (ret)
 				break;
 			code->op = FETCH_OP_DATA;
@@ -518,15 +807,24 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 		} else {
 			ret = str_to_immediate(arg + 1, &code->immediate);
 			if (ret)
-				trace_probe_log_err(offs + 1, BAD_IMM);
+				trace_probe_log_err(ctx->offset + 1, BAD_IMM);
 			else
 				code->op = FETCH_OP_IMM;
 		}
 		break;
+	default:
+		if (isalpha(arg[0]) || arg[0] == '_') {	/* BTF variable */
+			if (!tparg_is_function_entry(ctx->flags)) {
+				trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
+				return -EINVAL;
+			}
+			ret = parse_btf_arg(arg, code, ctx);
+			break;
+		}
 	}
 	if (!ret && code->op == FETCH_OP_NOP) {
 		/* Parsed, but do not find fetch method */
-		trace_probe_log_err(offs, BAD_FETCH_ARG);
+		trace_probe_log_err(ctx->offset, BAD_FETCH_ARG);
 		ret = -EINVAL;
 	}
 	return ret;
@@ -571,12 +869,13 @@ static int __parse_bitfield_probe_arg(const char *bf,
 
 /* String length checking wrapper */
 static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
-		struct probe_arg *parg, unsigned int flags, int offset)
+					   struct probe_arg *parg,
+					   struct traceprobe_parse_context *ctx)
 {
 	struct fetch_insn *code, *scode, *tmp = NULL;
 	char *t, *t2, *t3;
-	char *arg;
 	int ret, len;
+	char *arg;
 
 	arg = kstrdup(argv, GFP_KERNEL);
 	if (!arg)
@@ -585,10 +884,10 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	ret = -EINVAL;
 	len = strlen(arg);
 	if (len > MAX_ARGSTR_LEN) {
-		trace_probe_log_err(offset, ARG_TOO_LONG);
+		trace_probe_log_err(ctx->offset, ARG_TOO_LONG);
 		goto out;
 	} else if (len == 0) {
-		trace_probe_log_err(offset, NO_ARG_BODY);
+		trace_probe_log_err(ctx->offset, NO_ARG_BODY);
 		goto out;
 	}
 
@@ -606,23 +905,24 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 			*t2++ = '\0';
 			t3 = strchr(t2, ']');
 			if (!t3) {
-				offset += t2 + strlen(t2) - arg;
-				trace_probe_log_err(offset,
+				int offs = t2 + strlen(t2) - arg;
+
+				trace_probe_log_err(ctx->offset + offs,
 						    ARRAY_NO_CLOSE);
 				goto out;
 			} else if (t3[1] != '\0') {
-				trace_probe_log_err(offset + t3 + 1 - arg,
+				trace_probe_log_err(ctx->offset + t3 + 1 - arg,
 						    BAD_ARRAY_SUFFIX);
 				goto out;
 			}
 			*t3 = '\0';
 			if (kstrtouint(t2, 0, &parg->count) || !parg->count) {
-				trace_probe_log_err(offset + t2 - arg,
+				trace_probe_log_err(ctx->offset + t2 - arg,
 						    BAD_ARRAY_NUM);
 				goto out;
 			}
 			if (parg->count > MAX_ARRAY_LEN) {
-				trace_probe_log_err(offset + t2 - arg,
+				trace_probe_log_err(ctx->offset + t2 - arg,
 						    ARRAY_TOO_BIG);
 				goto out;
 			}
@@ -633,17 +933,17 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	 * Since $comm and immediate string can not be dereferenced,
 	 * we can find those by strcmp. But ignore for eprobes.
 	 */
-	if (!(flags & TPARG_FL_TPOINT) &&
+	if (!(ctx->flags & TPARG_FL_TEVENT) &&
 	    (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0 ||
 	     strncmp(arg, "\\\"", 2) == 0)) {
 		/* The type of $comm must be "string", and not an array. */
 		if (parg->count || (t && strcmp(t, "string")))
 			goto out;
-		parg->type = find_fetch_type("string", flags);
+		parg->type = find_fetch_type("string", ctx->flags);
 	} else
-		parg->type = find_fetch_type(t, flags);
+		parg->type = find_fetch_type(t, ctx->flags);
 	if (!parg->type) {
-		trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE);
+		trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_TYPE);
 		goto out;
 	}
 	parg->offset = *size;
@@ -665,10 +965,18 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	code[FETCH_INSN_MAX - 1].op = FETCH_OP_END;
 
 	ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1],
-			      flags, offset);
+			      ctx);
 	if (ret)
 		goto fail;
 
+	/* Update storing type if BTF is available */
+	if (IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS) && !t) {
+		if (code->op == FETCH_OP_ARG)
+			parg->type = parse_btf_arg_type(code->param, ctx);
+		else if (code->op == FETCH_OP_RETVAL)
+			parg->type = parse_btf_retval_type(ctx);
+	}
+
 	ret = -EINVAL;
 	/* Store operation */
 	if (parg->type->is_string) {
@@ -676,7 +984,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 			if (code->op != FETCH_OP_REG && code->op != FETCH_OP_STACK &&
 			    code->op != FETCH_OP_RETVAL && code->op != FETCH_OP_ARG &&
 			    code->op != FETCH_OP_DEREF && code->op != FETCH_OP_TP_ARG) {
-				trace_probe_log_err(offset + (t ? (t - arg) : 0),
+				trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0),
 						    BAD_SYMSTRING);
 				goto fail;
 			}
@@ -684,7 +992,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 			if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF &&
 			    code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM &&
 			    code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) {
-				trace_probe_log_err(offset + (t ? (t - arg) : 0),
+				trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0),
 						    BAD_STRING);
 				goto fail;
 			}
@@ -703,7 +1011,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 			 */
 			code++;
 			if (code->op != FETCH_OP_NOP) {
-				trace_probe_log_err(offset, TOO_MANY_OPS);
+				trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 				goto fail;
 			}
 		}
@@ -726,7 +1034,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	} else {
 		code++;
 		if (code->op != FETCH_OP_NOP) {
-			trace_probe_log_err(offset, TOO_MANY_OPS);
+			trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 			goto fail;
 		}
 		code->op = FETCH_OP_ST_RAW;
@@ -737,7 +1045,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	if (t != NULL) {
 		ret = __parse_bitfield_probe_arg(t, parg->type, &code);
 		if (ret) {
-			trace_probe_log_err(offset + t - arg, BAD_BITFIELD);
+			trace_probe_log_err(ctx->offset + t - arg, BAD_BITFIELD);
 			goto fail;
 		}
 	}
@@ -747,13 +1055,13 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 		if (scode->op != FETCH_OP_ST_MEM &&
 		    scode->op != FETCH_OP_ST_STRING &&
 		    scode->op != FETCH_OP_ST_USTRING) {
-			trace_probe_log_err(offset + (t ? (t - arg) : 0),
+			trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0),
 					    BAD_STRING);
 			goto fail;
 		}
 		code++;
 		if (code->op != FETCH_OP_NOP) {
-			trace_probe_log_err(offset, TOO_MANY_OPS);
+			trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
 			goto fail;
 		}
 		code->op = FETCH_OP_LP_ARRAY;
@@ -801,8 +1109,35 @@ static int traceprobe_conflict_field_name(const char *name,
 	return 0;
 }
 
+static char *generate_probe_arg_name(const char *arg, int idx)
+{
+	char *name = NULL;
+	const char *end;
+
+	/*
+	 * If argument name is omitted, try arg as a name (BTF variable)
+	 * or "argN".
+	 */
+	if (IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS)) {
+		end = strchr(arg, ':');
+		if (!end)
+			end = arg + strlen(arg);
+
+		name = kmemdup_nul(arg, end - arg, GFP_KERNEL);
+		if (!name || !is_good_name(name)) {
+			kfree(name);
+			name = NULL;
+		}
+	}
+
+	if (!name)
+		name = kasprintf(GFP_KERNEL, "arg%d", idx + 1);
+
+	return name;
+}
+
 int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg,
-				unsigned int flags)
+			       struct traceprobe_parse_context *ctx)
 {
 	struct probe_arg *parg = &tp->args[i];
 	const char *body;
@@ -822,8 +1157,7 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg,
 		parg->name = kmemdup_nul(arg, body - arg, GFP_KERNEL);
 		body++;
 	} else {
-		/* If argument name is omitted, set "argN" */
-		parg->name = kasprintf(GFP_KERNEL, "arg%d", i + 1);
+		parg->name = generate_probe_arg_name(arg, i);
 		body = arg;
 	}
 	if (!parg->name)
@@ -837,9 +1171,9 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg,
 		trace_probe_log_err(0, USED_ARG_NAME);
 		return -EINVAL;
 	}
+	ctx->offset = body - arg;
 	/* Parse fetch argument */
-	return traceprobe_parse_probe_arg_body(body, &tp->size, parg, flags,
-					       body - arg);
+	return traceprobe_parse_probe_arg_body(body, &tp->size, parg, ctx);
 }
 
 void traceprobe_free_probe_arg(struct probe_arg *arg)
@@ -858,6 +1192,151 @@ void traceprobe_free_probe_arg(struct probe_arg *arg)
 	kfree(arg->fmt);
 }
 
+static int argv_has_var_arg(int argc, const char *argv[], int *args_idx,
+			    struct traceprobe_parse_context *ctx)
+{
+	int i, found = 0;
+
+	for (i = 0; i < argc; i++)
+		if (str_has_prefix(argv[i], "$arg")) {
+			trace_probe_log_set_index(i + 2);
+
+			if (!tparg_is_function_entry(ctx->flags)) {
+				trace_probe_log_err(0, NOFENTRY_ARGS);
+				return -EINVAL;
+			}
+
+			if (isdigit(argv[i][4])) {
+				found = 1;
+				continue;
+			}
+
+			if (argv[i][4] != '*') {
+				trace_probe_log_err(0, BAD_VAR);
+				return -EINVAL;
+			}
+
+			if (*args_idx >= 0 && *args_idx < argc) {
+				trace_probe_log_err(0, DOUBLE_ARGS);
+				return -EINVAL;
+			}
+			found = 1;
+			*args_idx = i;
+		}
+
+	return found;
+}
+
+static int sprint_nth_btf_arg(int idx, const char *type,
+			      char *buf, int bufsize,
+			      struct traceprobe_parse_context *ctx)
+{
+	struct btf *btf = traceprobe_get_btf();
+	const char *name;
+	int ret;
+
+	if (idx >= ctx->nr_params) {
+		trace_probe_log_err(0, NO_BTFARG);
+		return -ENOENT;
+	}
+	name = btf_name_by_offset(btf, ctx->params[idx].name_off);
+	if (!name) {
+		trace_probe_log_err(0, NO_BTF_ENTRY);
+		return -ENOENT;
+	}
+	ret = snprintf(buf, bufsize, "%s%s", name, type);
+	if (ret >= bufsize) {
+		trace_probe_log_err(0, ARGS_2LONG);
+		return -E2BIG;
+	}
+	return ret;
+}
+
+/* Return new_argv which must be freed after use */
+const char **traceprobe_expand_meta_args(int argc, const char *argv[],
+					 int *new_argc, char *buf, int bufsize,
+					 struct traceprobe_parse_context *ctx)
+{
+	const struct btf_param *params = NULL;
+	int i, j, n, used, ret, args_idx = -1;
+	const char **new_argv = NULL;
+	int nr_params;
+
+	ret = argv_has_var_arg(argc, argv, &args_idx, ctx);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	if (!ret) {
+		*new_argc = argc;
+		return NULL;
+	}
+
+	params = find_btf_func_param(ctx->funcname, &nr_params,
+				     ctx->flags & TPARG_FL_TPOINT);
+	if (IS_ERR(params)) {
+		if (args_idx != -1) {
+			/* $arg* requires BTF info */
+			trace_probe_log_err(0, NOSUP_BTFARG);
+			return (const char **)params;
+		}
+		*new_argc = argc;
+		return NULL;
+	}
+	ctx->params = params;
+	ctx->nr_params = nr_params;
+
+	if (args_idx >= 0)
+		*new_argc = argc + ctx->nr_params - 1;
+	else
+		*new_argc = argc;
+
+	new_argv = kcalloc(*new_argc, sizeof(char *), GFP_KERNEL);
+	if (!new_argv)
+		return ERR_PTR(-ENOMEM);
+
+	used = 0;
+	for (i = 0, j = 0; i < argc; i++) {
+		trace_probe_log_set_index(i + 2);
+		if (i == args_idx) {
+			for (n = 0; n < nr_params; n++) {
+				ret = sprint_nth_btf_arg(n, "", buf + used,
+							 bufsize - used, ctx);
+				if (ret < 0)
+					goto error;
+
+				new_argv[j++] = buf + used;
+				used += ret + 1;
+			}
+			continue;
+		}
+
+		if (str_has_prefix(argv[i], "$arg")) {
+			char *type = NULL;
+
+			n = simple_strtoul(argv[i] + 4, &type, 10);
+			if (type && !(*type == ':' || *type == '\0')) {
+				trace_probe_log_err(0, BAD_VAR);
+				ret = -ENOENT;
+				goto error;
+			}
+			/* Note: $argN starts from $arg1 */
+			ret = sprint_nth_btf_arg(n - 1, type, buf + used,
+						 bufsize - used, ctx);
+			if (ret < 0)
+				goto error;
+			new_argv[j++] = buf + used;
+			used += ret + 1;
+		} else
+			new_argv[j++] = argv[i];
+	}
+
+	return new_argv;
+
+error:
+	kfree(new_argv);
+	return ERR_PTR(ret);
+}
+
 int traceprobe_update_arg(struct probe_arg *arg)
 {
 	struct fetch_insn *code = arg->code;
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 6a4ecfb1da43..01ea148723de 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -23,6 +23,7 @@
 #include <linux/limits.h>
 #include <linux/uaccess.h>
 #include <linux/bitops.h>
+#include <linux/btf.h>
 #include <asm/bitsperlong.h>
 
 #include "trace.h"
@@ -32,7 +33,9 @@
 #define MAX_ARGSTR_LEN		63
 #define MAX_ARRAY_LEN		64
 #define MAX_ARG_NAME_LEN	32
+#define MAX_BTF_ARGS_LEN	128
 #define MAX_STRING_SIZE		PATH_MAX
+#define MAX_ARG_BUF_LEN		(MAX_TRACE_ARGS * MAX_ARG_NAME_LEN)
 
 /* Reserved field names */
 #define FIELD_STRING_IP		"__probe_ip"
@@ -357,15 +360,42 @@ int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_a
 #define trace_probe_for_each_link_rcu(pos, tp)	\
 	list_for_each_entry_rcu(pos, &(tp)->event->files, list)
 
+/*
+ * The flags used for parsing trace_probe arguments.
+ * TPARG_FL_RETURN, TPARG_FL_FENTRY and TPARG_FL_TEVENT are mutually exclusive.
+ * TPARG_FL_KERNEL and TPARG_FL_USER are also mutually exclusive.
+ * TPARG_FL_FPROBE and TPARG_FL_TPOINT are optional but it should be with
+ * TPARG_FL_KERNEL.
+ */
 #define TPARG_FL_RETURN BIT(0)
 #define TPARG_FL_KERNEL BIT(1)
 #define TPARG_FL_FENTRY BIT(2)
-#define TPARG_FL_TPOINT BIT(3)
+#define TPARG_FL_TEVENT BIT(3)
 #define TPARG_FL_USER   BIT(4)
-#define TPARG_FL_MASK	GENMASK(4, 0)
+#define TPARG_FL_FPROBE BIT(5)
+#define TPARG_FL_TPOINT BIT(6)
+#define TPARG_FL_LOC_MASK	GENMASK(4, 0)
+
+static inline bool tparg_is_function_entry(unsigned int flags)
+{
+	return (flags & TPARG_FL_LOC_MASK) == (TPARG_FL_KERNEL | TPARG_FL_FENTRY);
+}
+
+struct traceprobe_parse_context {
+	struct trace_event_call *event;
+	const struct btf_param *params;
+	s32 nr_params;
+	const char *funcname;
+	unsigned int flags;
+	int offset;
+};
 
 extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
-				const char *argv, unsigned int flags);
+				      const char *argv,
+				      struct traceprobe_parse_context *ctx);
+const char **traceprobe_expand_meta_args(int argc, const char *argv[],
+					 int *new_argc, char *buf, int bufsize,
+					 struct traceprobe_parse_context *ctx);
 
 extern int traceprobe_update_arg(struct probe_arg *arg);
 extern void traceprobe_free_probe_arg(struct probe_arg *arg);
@@ -404,11 +434,12 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(REFCNT_OPEN_BRACE,	"Reference counter brace is not closed"), \
 	C(BAD_REFCNT_SUFFIX,	"Reference counter has wrong suffix"),	\
 	C(BAD_UPROBE_OFFS,	"Invalid uprobe offset"),		\
-	C(MAXACT_NO_KPROBE,	"Maxactive is not for kprobe"),		\
+	C(BAD_MAXACT_TYPE,	"Maxactive is only for function exit"),	\
 	C(BAD_MAXACT,		"Invalid maxactive number"),		\
 	C(MAXACT_TOO_BIG,	"Maxactive is too big"),		\
 	C(BAD_PROBE_ADDR,	"Invalid probed address or symbol"),	\
 	C(BAD_RETPROBE,		"Retprobe address must be an function entry"), \
+	C(NO_TRACEPOINT,	"Tracepoint is not found"),		\
 	C(BAD_ADDR_SUFFIX,	"Invalid probed address suffix"), \
 	C(NO_GROUP_NAME,	"Group name is not specified"),		\
 	C(GROUP_TOO_LONG,	"Group name is too long"),		\
@@ -418,6 +449,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(BAD_EVENT_NAME,	"Event name must follow the same rules as C identifiers"), \
 	C(EVENT_EXIST,		"Given group/event name is already used by another event"), \
 	C(RETVAL_ON_PROBE,	"$retval is not available on probe"),	\
+	C(NO_RETVAL,		"This function returns 'void' type"),	\
 	C(BAD_STACK_NUM,	"Invalid stack number"),		\
 	C(BAD_ARG_NUM,		"Invalid argument number"),		\
 	C(BAD_VAR,		"Invalid $-valiable specified"),	\
@@ -456,7 +488,14 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(NO_EVENT_INFO,	"This requires both group and event name to attach"),\
 	C(BAD_ATTACH_EVENT,	"Attached event does not exist"),\
 	C(BAD_ATTACH_ARG,	"Attached event does not have this field"),\
-	C(NO_EP_FILTER,		"No filter rule after 'if'"),
+	C(NO_EP_FILTER,		"No filter rule after 'if'"),		\
+	C(NOSUP_BTFARG,		"BTF is not available or not supported"),	\
+	C(NO_BTFARG,		"This variable is not found at this probe point"),\
+	C(NO_BTF_ENTRY,		"No BTF entry for this probe point"),	\
+	C(BAD_VAR_ARGS,		"$arg* must be an independent parameter without name etc."),\
+	C(NOFENTRY_ARGS,	"$arg* can be used only on function entry"),	\
+	C(DOUBLE_ARGS,		"$arg* can be used only once in the parameters"),	\
+	C(ARGS_2LONG,		"$arg* failed because the argument list is too long"),
 
 #undef C
 #define C(a, b)		TP_ERR_##a
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 8b92e34ff0c8..fa09b33ee731 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -686,10 +686,12 @@ static int __trace_uprobe_create(int argc, const char **argv)
 
 	/* parse arguments */
 	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+		struct traceprobe_parse_context ctx = {
+			.flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER,
+		};
+
 		trace_probe_log_set_index(i + 2);
-		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i],
-					(is_return ? TPARG_FL_RETURN : 0) |
-					TPARG_FL_USER);
+		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], &ctx);
 		if (ret)
 			goto error;
 	}