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 <rostedt@goodmis.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2016-07-27 12:17:35 +09:30
parent 0ef7653797
commit bdc9f37355

View File

@ -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,