+// SPDX-License-Identifier: GPL-2.0
/*
* Kprobes-based tracing events
*
* Created by Masami Hiramatsu <mhiramat@redhat.com>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define pr_fmt(fmt) "trace_kprobe: " fmt
#include <linux/rculist.h>
#include <linux/error-injection.h>
+#include "trace_kprobe_selftest.h"
#include "trace_probe.h"
#define KPROBE_EVENT_SYSTEM "kprobes"
return nhit;
}
+/* Return 0 if it fails to find the symbol address */
+static nokprobe_inline
+unsigned long trace_kprobe_address(struct trace_kprobe *tk)
+{
+ unsigned long addr;
+
+ if (tk->symbol) {
+ addr = (unsigned long)
+ kallsyms_lookup_name(trace_kprobe_symbol(tk));
+ if (addr)
+ addr += tk->rp.kp.offset;
+ } else {
+ addr = (unsigned long)tk->rp.kp.addr;
+ }
+ return addr;
+}
+
bool trace_kprobe_on_func_entry(struct trace_event_call *call)
{
struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
bool trace_kprobe_error_injectable(struct trace_event_call *call)
{
struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
- unsigned long addr;
- if (tk->symbol) {
- addr = (unsigned long)
- kallsyms_lookup_name(trace_kprobe_symbol(tk));
- addr += tk->rp.kp.offset;
- } else {
- addr = (unsigned long)tk->rp.kp.addr;
- }
- return within_error_injection_list(addr);
+ return within_error_injection_list(trace_kprobe_address(tk));
}
static int register_kprobe_event(struct trace_kprobe *tk);
return NULL;
}
+static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
+{
+ int ret = 0;
+
+ if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
+ if (trace_kprobe_is_return(tk))
+ ret = enable_kretprobe(&tk->rp);
+ else
+ ret = enable_kprobe(&tk->rp.kp);
+ }
+
+ return ret;
+}
+
/*
* Enable trace_probe
* if the file is NULL, enable "perf" handler, or enable "trace" handler.
static int
enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
{
- struct event_file_link *link = NULL;
+ struct event_file_link *link;
int ret = 0;
if (file) {
list_add_tail_rcu(&link->list, &tk->tp.files);
tk->tp.flags |= TP_FLAG_TRACE;
- } else
- tk->tp.flags |= TP_FLAG_PROFILE;
-
- if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
- if (trace_kprobe_is_return(tk))
- ret = enable_kretprobe(&tk->rp);
- else
- ret = enable_kprobe(&tk->rp.kp);
- }
-
- if (ret) {
- if (file) {
- /* Notice the if is true on not WARN() */
- if (!WARN_ON_ONCE(!link))
- list_del_rcu(&link->list);
+ ret = __enable_trace_kprobe(tk);
+ if (ret) {
+ list_del_rcu(&link->list);
kfree(link);
tk->tp.flags &= ~TP_FLAG_TRACE;
- } else {
- tk->tp.flags &= ~TP_FLAG_PROFILE;
}
+
+ } else {
+ tk->tp.flags |= TP_FLAG_PROFILE;
+ ret = __enable_trace_kprobe(tk);
+ if (ret)
+ tk->tp.flags &= ~TP_FLAG_PROFILE;
}
out:
return ret;
return ret;
}
+#if defined(CONFIG_KPROBES_ON_FTRACE) && \
+ !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
+static bool within_notrace_func(struct trace_kprobe *tk)
+{
+ unsigned long offset, size, addr;
+
+ addr = trace_kprobe_address(tk);
+ if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
+ return false;
+
+ /* Get the entry address of the target function */
+ addr -= offset;
+
+ /*
+ * Since ftrace_location_range() does inclusive range check, we need
+ * to subtract 1 byte from the end address.
+ */
+ return !ftrace_location_range(addr, addr + size - 1);
+}
+#else
+#define within_notrace_func(tk) (false)
+#endif
+
/* Internal register function - just handle k*probes and flags */
static int __register_trace_kprobe(struct trace_kprobe *tk)
{
if (trace_probe_is_registered(&tk->tp))
return -EINVAL;
+ if (within_notrace_func(tk)) {
+ pr_warn("Could not probe notrace function %s\n",
+ trace_kprobe_symbol(tk));
+ return -EINVAL;
+ }
+
for (i = 0; i < tk->tp.nr_args; i++)
traceprobe_update_arg(&tk->tp.args[i]);
#ifdef CONFIG_FTRACE_STARTUP_TEST
-/*
- * The "__used" keeps gcc from removing the function symbol
- * from the kallsyms table. 'noinline' makes sure that there
- * isn't an inlined version used by the test method below
- */
-static __used __init noinline int
-kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6)
-{
- return a1 + a2 + a3 + a4 + a5 + a6;
-}
-
static __init struct trace_event_file *
find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
{
git.samba.org / sfrench / cifs-2.6.git / blobdiff