From: Sebastian Andrzej Siewior Date: Wed, 8 Jan 2025 09:04:44 +0000 (+0100) Subject: module: Use RCU in all users of __module_text_address(). X-Git-Tag: v6.15-rc1~94^2~17 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d593e0cabdf6428560f311af0657642979b2c8ad;p=thirdparty%2Flinux.git module: Use RCU in all users of __module_text_address(). __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. Signed-off-by: Sebastian Andrzej Siewior Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250108090457.512198-16-bigeasy@linutronix.de Signed-off-by: Petr Pavlu --- diff --git a/kernel/module/main.c b/kernel/module/main.c index 8a8b499730d86..81ecb9d3a9353 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -823,13 +823,12 @@ void symbol_put_addr(void *addr) /* * Even though we hold a reference on the module; we still need to - * disable preemption in order to safely traverse the data structure. + * RCU read section in order to safely traverse the data structure. */ - preempt_disable(); + guard(rcu)(); modaddr = __module_text_address(a); BUG_ON(!modaddr); module_put(modaddr); - preempt_enable(); } EXPORT_SYMBOL_GPL(symbol_put_addr); @@ -3776,20 +3775,15 @@ lookup: */ bool is_module_text_address(unsigned long addr) { - bool ret; - - preempt_disable(); - ret = __module_text_address(addr) != NULL; - preempt_enable(); - - return ret; + guard(rcu)(); + return __module_text_address(addr) != NULL; } /** * __module_text_address() - get the module whose code contains an address. * @addr: the address. * - * Must be called with preempt disabled or module mutex held so that + * Must be called within RCU read section or module mutex held so that * module doesn't get freed during this. */ struct module *__module_text_address(unsigned long addr)