[PATCH] kprobes: Fix to init kprobes in subsys_initcall

From: Masami Hiramatsu
Date: Mon Jun 03 2019 - 09:08:35 EST


Since arm64 kernel initializes breakpoint trap vector in arch_initcall(),
initializing kprobe (and run smoke test) in postcore_initcall() causes
a kernel panic.

To fix this issue, move the kprobe initialization in subsys_initcall()
(which is called right afer the arch_initcall).

In-kernel kprobe users (ftrace and bpf) are using fs_initcall() which is
called after subsys_initcall(), so this shouldn't cause more problem.

Reported-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
Fixes: b5f8b32c93b2 ("kprobes: Initialize kprobes at postcore_initcall")
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
kernel/kprobes.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 54aaaad00a47..5471efbeb937 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2289,7 +2289,7 @@ static int __init init_kprobes(void)
init_test_probes();
return err;
}
-postcore_initcall(init_kprobes);
+subsys_initcall(init_kprobes);

#ifdef CONFIG_DEBUG_FS
static void report_probe(struct seq_file *pi, struct kprobe *p,