PM: Print a warning if firmware is requested when tasks are frozen
Some drivers erroneously use request_firmware() from their ->resume()
(or ->thaw(), or ->restore()) callbacks, which is not going to work
unless the firmware has been built in. This causes system resume to
stall until the firmware-loading timeout expires, which makes users
think that the resume has failed and reboot their machines
unnecessarily. For this reason, make _request_firmware() print a
warning and return immediately with error code if it has been called
when tasks are frozen and it's impossible to start any new usermode
helpers.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 8c798ef..bbb03e6 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -521,6 +521,11 @@
if (!firmware_p)
return -EINVAL;
+ if (WARN_ON(usermodehelper_is_disabled())) {
+ dev_err(device, "firmware: %s will not be loaded\n", name);
+ return -EBUSY;
+ }
+
*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
if (!firmware) {
dev_err(device, "%s: kmalloc(struct firmware) failed\n",
