From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Luis Chamberlain <mcgrof@kernel.org>, linux-modules@vger.kernel.org
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>,
linux-kernel@vger.kernel.org
Subject: [PATCH v2 2/2] module: Increase readability of module_kallsyms_lookup_name()
Date: Mon, 13 Jun 2022 08:02:02 +0200 [thread overview]
Message-ID: <133321ea63ceb4cdd83346e068d1d16b676678f8.1655100096.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <f15dcfd75e064f80eeb75c9baf9e881196039db7.1655100096.git.christophe.leroy@csgroup.eu>
module_kallsyms_lookup_name() has several exit conditions but
can't return immediately due to preempt_disable().
Refactor module_kallsyms_lookup_name() to allow returning from
anywhere, and reduce depth.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
kernel/module/kallsyms.c | 38 ++++++++++++++++++++++++--------------
1 file changed, 24 insertions(+), 14 deletions(-)
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
index fe3636bde605..df0150c467d4 100644
--- a/kernel/module/kallsyms.c
+++ b/kernel/module/kallsyms.c
@@ -448,29 +448,39 @@ unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
return 0;
}
-/* Look for this name: can be of form module:name. */
-unsigned long module_kallsyms_lookup_name(const char *name)
+static unsigned long __module_kallsyms_lookup_name(const char *name)
{
struct module *mod;
char *colon;
- unsigned long ret = 0;
- /* Don't lock: we're in enough trouble already. */
- preempt_disable();
colon = strnchr(name, MODULE_NAME_LEN, ':');
if (colon) {
mod = find_module_all(name, colon - name, false);
if (mod)
- ret = find_kallsyms_symbol_value(mod, colon + 1);
- } else {
- list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- ret = find_kallsyms_symbol_value(mod, name);
- if (ret)
- break;
- }
+ return find_kallsyms_symbol_value(mod, colon + 1);
+ return 0;
}
+
+ list_for_each_entry_rcu(mod, &modules, list) {
+ unsigned long ret;
+
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+ ret = find_kallsyms_symbol_value(mod, name);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/* Look for this name: can be of form module:name. */
+unsigned long module_kallsyms_lookup_name(const char *name)
+{
+ unsigned long ret;
+
+ /* Don't lock: we're in enough trouble already. */
+ preempt_disable();
+ ret = __module_kallsyms_lookup_name(name);
preempt_enable();
return ret;
}
--
2.35.3
next prev parent reply other threads:[~2022-06-13 6:02 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-13 6:02 [PATCH v2 1/2] module: Fix ERRORs reported by checkpatch.pl Christophe Leroy
2022-06-13 6:02 ` Christophe Leroy [this message]
2022-07-01 22:07 ` [PATCH v2 2/2] module: Increase readability of module_kallsyms_lookup_name() Luis Chamberlain
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