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module: Use RCU in all users of __module_text_address().

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__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 <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-16-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
This commit is contained in:
Sebastian Andrzej Siewior 2025-01-08 10:04:44 +01:00 committed by Petr Pavlu
parent 6593a2c990
commit d593e0cabd
1 changed files with 5 additions and 11 deletions
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16
kernel/module/main.c
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@ -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)