[tip:perf/core] kprobes: Prohibit probing on hardirq tracers

tip-bot for Masami Hiramatsu
2019-02-13T09:03:51Z

Commit-ID: eeeb080bae906a57b6513d37efe3c38f2cb87a1c
Gitweb: https://git.kernel.org/tip/eeeb080bae906a57b6513d37efe3c38f2cb87a1c
Author: Masami Hiramatsu <mhiramat@kernel.org>
AuthorDate: Wed, 13 Feb 2019 01:13:40 +0900
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Wed, 13 Feb 2019 08:16:40 +0100

kprobes: Prohibit probing on hardirq tracers

Since kprobes breakpoint handling involves hardirq tracer,
probing these functions cause breakpoint recursion problem.

Prohibit probing on those functions.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998802073.31052.17255044712514564153.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/trace/trace_irqsoff.c | 9 +++++++--
kernel/trace/trace_preemptirq.c | 5 +++++
2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index d3294721f119..d42a473b8240 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -14,6 +14,7 @@
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/ftrace.h>
+#include <linux/kprobes.h>

#include "trace.h"

@@ -365,7 +366,7 @@ out:
__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
}

-static inline void
+static nokprobe_inline void
start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
{
int cpu;
@@ -401,7 +402,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
atomic_dec(&data->disabled);
}

-static inline void
+static nokprobe_inline void
stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
{
int cpu;
@@ -443,6 +444,7 @@ void start_critical_timings(void)
start_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
}
EXPORT_SYMBOL_GPL(start_critical_timings);
+NOKPROBE_SYMBOL(start_critical_timings);

void stop_critical_timings(void)
{
@@ -452,6 +454,7 @@ void stop_critical_timings(void)
stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
}
EXPORT_SYMBOL_GPL(stop_critical_timings);
+NOKPROBE_SYMBOL(stop_critical_timings);

#ifdef CONFIG_FUNCTION_TRACER
static bool function_enabled;
@@ -611,6 +614,7 @@ void tracer_hardirqs_on(unsigned long a0, unsigned long a1)
if (!preempt_trace(pc) && irq_trace())
stop_critical_timing(a0, a1, pc);
}
+NOKPROBE_SYMBOL(tracer_hardirqs_on);

void tracer_hardirqs_off(unsigned long a0, unsigned long a1)
{
@@ -619,6 +623,7 @@ void tracer_hardirqs_off(unsigned long a0, unsigned long a1)
if (!preempt_trace(pc) && irq_trace())
start_critical_timing(a0, a1, pc);
}
+NOKPROBE_SYMBOL(tracer_hardirqs_off);

static int irqsoff_tracer_init(struct trace_array *tr)
{
diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c
index 71f553cceb3c..4d8e99fdbbbe 100644
--- a/kernel/trace/trace_preemptirq.c
+++ b/kernel/trace/trace_preemptirq.c
@@ -9,6 +9,7 @@
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/ftrace.h>
+#include <linux/kprobes.h>
#include "trace.h"

#define CREATE_TRACE_POINTS
@@ -30,6 +31,7 @@ void trace_hardirqs_on(void)
lockdep_hardirqs_on(CALLER_ADDR0);
}
EXPORT_SYMBOL(trace_hardirqs_on);
+NOKPROBE_SYMBOL(trace_hardirqs_on);

void trace_hardirqs_off(void)
{
@@ -43,6 +45,7 @@ void trace_hardirqs_off(void)
lockdep_hardirqs_off(CALLER_ADDR0);
}
EXPORT_SYMBOL(trace_hardirqs_off);
+NOKPROBE_SYMBOL(trace_hardirqs_off);

__visible void trace_hardirqs_on_caller(unsigned long caller_addr)
{
@@ -56,6 +59,7 @@ __visible void trace_hardirqs_on_caller(unsigned long caller_addr)
lockdep_hardirqs_on(CALLER_ADDR0);
}
EXPORT_SYMBOL(trace_hardirqs_on_caller);
+NOKPROBE_SYMBOL(trace_hardirqs_on_caller);

__visible void trace_hardirqs_off_caller(unsigned long caller_addr)
{
@@ -69,6 +73,7 @@ __visible void trace_hardirqs_off_caller(unsigned long caller_addr)
lockdep_hardirqs_off(CALLER_ADDR0);
}
EXPORT_SYMBOL(trace_hardirqs_off_caller);
+NOKPROBE_SYMBOL(trace_hardirqs_off_caller);
#endif /* CONFIG_TRACE_IRQFLAGS */

#ifdef CONFIG_TRACE_PREEMPT_TOGGLE