driver core: Fix handling of SYNC_STATE_ONLY + STATELESS device links

Commit 21c27f06587d ("driver core: Fix SYNC_STATE_ONLY device link
implementation") didn't completely fix STATELESS + SYNC_STATE_ONLY
handling.

What looks like an optimization in that commit is actually a bug that
causes an if condition to always take the else path. This prevents
reordering of devices in the dpm_list when a DL_FLAG_STATELESS device
link is create on top of an existing DL_FLAG_SYNC_STATE_ONLY device
link.

Fixes: 21c27f06587d ("driver core: Fix SYNC_STATE_ONLY device link implementation")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200520043626.181820-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 4e0e430..0cad34f 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -360,12 +360,14 @@ struct device_link *device_link_add(struct device *consumer,
 
                if (flags & DL_FLAG_STATELESS) {
                        kref_get(&link->kref);
-                       link->flags |= DL_FLAG_STATELESS;
                        if (link->flags & DL_FLAG_SYNC_STATE_ONLY &&
-                           !(link->flags & DL_FLAG_STATELESS))
+                           !(link->flags & DL_FLAG_STATELESS)) {
+                               link->flags |= DL_FLAG_STATELESS;
                                goto reorder;
-                       else
+                       } else {
+                               link->flags |= DL_FLAG_STATELESS;
                                goto out;
+                       }
                }
 
                /*