[PATCH 2/5] firmware: fix capturing errors on fw_cache_init() on early init

From: Luis R. Rodriguez
Date: Mon Nov 20 2017 - 12:45:57 EST


register_pm_notifier() can technically fail, caputure this.
Note that register_syscore_ops() cannot fail given it just
adds an element to a linked list. This has been broken since
v3.7. Chances of this failing however are slim.

To improve code readability move the code folded under CONFIG_PM_SLEEP
into a helper.

Fixes: 07646d9c0938d ("firmware loader: cache devices firmware during suspend/resume cycle")
Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx>
---
drivers/base/firmware_class.c | 45 ++++++++++++++++++++++++++++++-------------
1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 149413a376cf..c8033c5488f9 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1768,6 +1768,26 @@ static struct syscore_ops fw_syscore_ops = {
.suspend = fw_suspend,
};

+static int __init register_fw_pm_ops(void)
+{
+ int ret;
+
+ spin_lock_init(&fw_cache.name_lock);
+ INIT_LIST_HEAD(&fw_cache.fw_names);
+
+ INIT_DELAYED_WORK(&fw_cache.work,
+ device_uncache_fw_images_work);
+
+ fw_cache.pm_notify.notifier_call = fw_pm_notify;
+ ret = register_pm_notifier(&fw_cache.pm_notify);
+ if (ret)
+ return ret;
+
+ register_syscore_ops(&fw_syscore_ops);
+
+ return ret;
+}
+
static inline void unregister_fw_pm_ops(void)
{
unregister_syscore_ops(&fw_syscore_ops);
@@ -1778,6 +1798,10 @@ static int fw_cache_piggyback_on_request(const char *name)
{
return 0;
}
+static inline int register_fw_pm_ops(void)
+{
+ return 0;
+}
static inline void unregister_fw_pm_ops(void)
{
}
@@ -1788,19 +1812,6 @@ static void __init fw_cache_init(void)
spin_lock_init(&fw_cache.lock);
INIT_LIST_HEAD(&fw_cache.head);
fw_cache.state = FW_LOADER_NO_CACHE;
-
-#ifdef CONFIG_PM_SLEEP
- spin_lock_init(&fw_cache.name_lock);
- INIT_LIST_HEAD(&fw_cache.fw_names);
-
- INIT_DELAYED_WORK(&fw_cache.work,
- device_uncache_fw_images_work);
-
- fw_cache.pm_notify.notifier_call = fw_pm_notify;
- register_pm_notifier(&fw_cache.pm_notify);
-
- register_syscore_ops(&fw_syscore_ops);
-#endif
}

static int fw_shutdown_notify(struct notifier_block *unused1,
@@ -1821,7 +1832,15 @@ static struct notifier_block fw_shutdown_nb = {

static int __init firmware_class_init(void)
{
+ int ret;
+
+ /* No need to unfold these on exit */
fw_cache_init();
+
+ ret = register_fw_pm_ops();
+ if (ret)
+ return ret;
+
register_reboot_notifier(&fw_shutdown_nb);
#ifdef CONFIG_FW_LOADER_USER_HELPER
return class_register(&firmware_class);
--
2.15.0