diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2017-05-17 10:19:49 +0200 |
|---|---|---|
| committer | Sasha Levin <alexander.levin@verizon.com> | 2017-06-08 06:12:46 -0400 |
| commit | e17762c03b3ee6ca56778f081cd1a4f4068fb1fb (patch) | |
| tree | 75d419ede25f4051dec5720ed74f08e826e0e464 /include | |
| parent | 78de28c67c8f3e46d4198982cff389ab986544ac (diff) | |
tracing/kprobes: Enforce kprobes teardown after testing
[ Upstream commit 30e7d894c1478c88d50ce94ddcdbd7f9763d9cdd ]
Enabling the tracer selftest triggers occasionally the warning in
text_poke(), which warns when the to be modified page is not marked
reserved.
The reason is that the tracer selftest installs kprobes on functions marked
__init for testing. These probes are removed after the tests, but that
removal schedules the delayed kprobes_optimizer work, which will do the
actual text poke. If the work is executed after the init text is freed,
then the warning triggers. The bug can be reproduced reliably when the work
delay is increased.
Flush the optimizer work and wait for the optimizing/unoptimizing lists to
become empty before returning from the kprobes tracer selftest. That
ensures that all operations which were queued due to the probes removal
have completed.
Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 6274de498 ("kprobes: Support delayed unoptimizing")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/kprobes.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 1ab54754a86d..14ce0feda692 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -328,7 +328,9 @@ extern int proc_kprobes_optimization_handler(struct ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos); #endif - +extern void wait_for_kprobe_optimizer(void); +#else +static inline void wait_for_kprobe_optimizer(void) { } #endif /* CONFIG_OPTPROBES */ #ifdef CONFIG_KPROBES_ON_FTRACE extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, |