driver core: skip removal test for non-removable drivers

Some drivers do not support removal/unbinding. These drivers should have drv->suppress_bind_attrs set to true, so use that to skip the removal test.

This doesn't fix anything reported so far, but should prevent some other cases. Some drivers will need fixes to set suppress_bind_attrs to avoid this test.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=177021

---
 drivers/base/dd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index d22a7260f42b..8937a7ad7165 100644
@@ -324,7 +324,8 @@ static int really_probe(struct device *dev, struct device_driver *drv)
 {
 	int ret = -EPROBE_DEFER;
 	int local_trigger_count = atomic_read(&deferred_trigger_count);
-	bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE);
+	bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) &&
+			   !drv->suppress_bind_attrs;
 
 	if (defer_all_probes) {
 		/*

2.10.0

Commit d42a09802174 (driver core: skip removal test for non-removable drivers) introduced a smatch warning:

drivers/base/dd.c:386 really_probe()

         warn: variable dereferenced before check 'dev->bus' (see line 373)

Fix the warning by removing the dev->bus NULL check. dev->bus will never be NULL, so the check was unnecessary.

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

index 8937a7ad7165..d76cd97a98b6 100644
@@ -384,7 +384,7 @@ static int really_probe(struct device *dev, struct device_driver *drv)
 	if (test_remove) {
 		test_remove = false;
 
-		if (dev->bus && dev->bus->remove)
+		if (dev->bus->remove)
 			dev->bus->remove(dev);
 		else if (drv->remove)
 			drv->remove(dev);

2.10.0

Hi Rob,