[PATCH 4.4 128/163] PM / Domains: Fix removal of a subdomain

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jon Hunter <jonathanh@xxxxxxxxxx>

commit beda5fc1ff9b527059290a97b672d2ee0eb7b92f upstream.

Commit 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use
before removing) added a test to ensure that a subdomain is not a
master to another subdomain or if any devices are using the subdomain
before removing. This change incorrectly used the "slave_links" list to
determine if the subdomain is a master to another subdomain, where it
should have been using the "master_links" list instead. The
"slave_links" list will never be empty for a subdomain and so a
subdomain can never be removed. Fix this by testing if the
"master_links" list is empty instead.

Fixes: 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing)
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Reviewed-by: Thierry Reding <treding@xxxxxxxxxx>
Acked-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Acked-by: Kevin Hilman <khilman@xxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/base/power/domain.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1381,7 +1381,7 @@ int pm_genpd_remove_subdomain(struct gen
 
 	mutex_lock(&genpd->lock);
 
-	if (!list_empty(&subdomain->slave_links) || subdomain->device_count) {
+	if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
 		pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
 			subdomain->name);
 		ret = -EBUSY;