From bdc9f373551dd3f1e6fae1618f2394ee9bc7db2e Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 27 Jul 2016 12:17:35 +0930 Subject: [PATCH] jump_label: disable preemption around __module_text_address(). Steven reported a warning caused by not holding module_mutex or rcu_read_lock_sched: his backtrace was corrupted but a quick audit found this possible cause. It's wrong anyway... Reported-by: Steven Rostedt Signed-off-by: Rusty Russell --- kernel/jump_label.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 0dbea88..0eef939 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -284,11 +284,14 @@ static int __jump_label_mod_text_reserved(void *start, void *end) { struct module *mod; + preempt_disable(); mod = __module_text_address((unsigned long)start); + WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod); + preempt_enable(); + if (!mod) return 0; - WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod); return __jump_label_text_reserved(mod->jump_entries, mod->jump_entries + mod->num_jump_entries, -- 2.7.4