Commit 1f0dfa05 authored by Saravana Kannan's avatar Saravana Kannan Committed by Greg Kroah-Hartman
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driver core: Add debug logs for device link related probe deferrals 



There's insufficient logging when device links or fw_devlink (waiting to
create device links) cause probe deferrals.  This makes it hard to debug
devices not getting probed. So, add debug logs to make it easy to debug.

Signed-off-by: default avatarSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201218031703.3053753-2-saravanak@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7520962b

drivers/base/core.c

+6 −0
Original line number Diff line number Diff line
@@ -929,6 +929,10 @@ int device_links_check_suppliers(struct device *dev) 
	mutex_lock(&fwnode_link_lock);

	if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) &&

	    !fw_devlink_is_permissive()) {

		dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n",

			list_first_entry(&dev->fwnode->suppliers,

			struct fwnode_link,

			c_hook)->supplier);

		mutex_unlock(&fwnode_link_lock);

		return -EPROBE_DEFER;

	}
@@ -943,6 +947,8 @@ int device_links_check_suppliers(struct device *dev) 
		if (link->status != DL_STATE_AVAILABLE &&

		    !(link->flags & DL_FLAG_SYNC_STATE_ONLY)) {

			device_links_missing_supplier(dev);

			dev_dbg(dev, "probe deferral - supplier %s not ready\n",

				dev_name(link->supplier));

			ret = -EPROBE_DEFER;

			break;

		}