[PATCH v3 24/28] jump_label: Use RCU in all users of __module_text_address().

[Sebastian Andrzej Siewior]

__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Cc: Ard Biesheuvel <a...@kernel.org>
Cc: Jason Baron <jba...@akamai.com>
Cc: Josh Poimboeuf <jpoim...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Steven Rostedt <rost...@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de>
---
 kernel/jump_label.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 7fcf4017cb383..7cb19e6014266 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -653,13 +653,12 @@ static int __jump_label_mod_text_reserved(void *start, 
void *end)
        struct module *mod;
        int ret;
 
-       preempt_disable();
-       mod = __module_text_address((unsigned long)start);
-       WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
-       if (!try_module_get(mod))
-               mod = NULL;
-       preempt_enable();
-
+       scoped_guard(rcu) {
+               mod = __module_text_address((unsigned long)start);
+               WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
+               if (!try_module_get(mod))
+                       mod = NULL;
+       }
        if (!mod)
                return 0;
 
-- 
2.47.1