diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2025-01-08 10:04:35 +0100 |
|---|---|---|
| committer | Petr Pavlu <petr.pavlu@suse.com> | 2025-03-10 11:54:44 +0100 |
| commit | febaa65c94e0db795ec52c45bf7ede524cdce63c (patch) | |
| tree | 2d5445742822458e87e0ccb54c87a9ee2534e017 /kernel/module | |
| parent | c4fadf38ded553edd6ea78ec6cc819e8fdd6f9d3 (diff) | |
module: Use RCU in find_module_all().
The modules list and module::kallsyms can be accessed under RCU
assumption.
Remove module_assert_mutex_or_preempt() from find_module_all() so it can
be used under RCU protection without warnings. Update its callers to use
RCU protection instead of preempt_disable().
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-trace-kernel@vger.kernel.org
Cc: live-patching@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250108090457.512198-7-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Diffstat (limited to 'kernel/module')
| -rw-r--r-- | kernel/module/kallsyms.c | 1 | ||||
| -rw-r--r-- | kernel/module/main.c | 6 |
2 files changed, 3 insertions, 4 deletions
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c index 4eef518204eb..3cba9f933b24 100644 --- a/kernel/module/kallsyms.c +++ b/kernel/module/kallsyms.c @@ -450,6 +450,7 @@ unsigned long module_kallsyms_lookup_name(const char *name) unsigned long ret; /* Don't lock: we're in enough trouble already. */ + guard(rcu)(); preempt_disable(); ret = __module_kallsyms_lookup_name(name); preempt_enable(); diff --git a/kernel/module/main.c b/kernel/module/main.c index 5f661d5343ac..cdd403b940b0 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -374,16 +374,14 @@ bool find_symbol(struct find_symbol_arg *fsa) } /* - * Search for module by name: must hold module_mutex (or preempt disabled - * for read-only access). + * Search for module by name: must hold module_mutex (or RCU for read-only + * access). */ struct module *find_module_all(const char *name, size_t len, bool even_unformed) { struct module *mod; - module_assert_mutex_or_preempt(); - list_for_each_entry_rcu(mod, &modules, list, lockdep_is_held(&module_mutex)) { if (!even_unformed && mod->state == MODULE_STATE_UNFORMED) |