Merge patch series "scsi: libsas: Fix the failure of adding phy with zero-address to new port"

Xingui Yang <yangxingui@huawei.com> says:

This series is to solve the problem of a BUG() when adding phy with
zero address to a new port.

Link: https://lore.kernel.org/r/20240312141103.31358-1-yangxingui@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: martinkpetersen

drivers/scsi/libsas/sas_expander.c

@@ -26,6 +26,28 @@ static int sas_configure_phy(struct domain_device *dev, int phy_id,
 			     u8 *sas_addr, int include);
 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
 
+static void sas_port_add_ex_phy(struct sas_port *port, struct ex_phy *ex_phy)
+{
+	sas_port_add_phy(port, ex_phy->phy);
+	ex_phy->port = port;
+	ex_phy->phy_state = PHY_DEVICE_DISCOVERED;
+}
+
+static void sas_ex_add_parent_port(struct domain_device *dev, int phy_id)
+{
+	struct expander_device *ex = &dev->ex_dev;
+	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
+
+	if (!ex->parent_port) {
+		ex->parent_port = sas_port_alloc(&dev->rphy->dev, phy_id);
+		/* FIXME: error handling */
+		BUG_ON(!ex->parent_port);
+		BUG_ON(sas_port_add(ex->parent_port));
+		sas_port_mark_backlink(ex->parent_port);
+	}
+	sas_port_add_ex_phy(ex->parent_port, ex_phy);
+}
+
 /* ---------- SMP task management ---------- */
 
 /* Give it some long enough timeout. In seconds. */
@@ -239,8 +261,7 @@ static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
 	/* help some expanders that fail to zero sas_address in the 'no
 	 * device' case
 	 */
-	if (phy->attached_dev_type == SAS_PHY_UNUSED ||
-	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
+	if (phy->attached_dev_type == SAS_PHY_UNUSED)
 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
 	else
 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
@@ -857,9 +878,7 @@ static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
 
 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
 			    SAS_ADDR_SIZE) && ephy->port) {
-			sas_port_add_phy(ephy->port, phy->phy);
-			phy->port = ephy->port;
-			phy->phy_state = PHY_DEVICE_DISCOVERED;
+			sas_port_add_ex_phy(ephy->port, phy);
 			return true;
 		}
 	}
@@ -963,11 +982,11 @@ static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
 
 	/* Parent and domain coherency */
 	if (!dev->parent && sas_phy_match_port_addr(dev->port, ex_phy)) {
-		sas_add_parent_port(dev, phy_id);
+		sas_ex_add_parent_port(dev, phy_id);
 		return 0;
 	}
 	if (dev->parent && sas_phy_match_dev_addr(dev->parent, ex_phy)) {
-		sas_add_parent_port(dev, phy_id);
+		sas_ex_add_parent_port(dev, phy_id);
 		if (ex_phy->routing_attr == TABLE_ROUTING)
 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
 		return 0;
@@ -1849,9 +1868,12 @@ static void sas_unregister_devs_sas_addr(struct domain_device *parent,
 	if (phy->port) {
 		sas_port_delete_phy(phy->port, phy->phy);
 		sas_device_set_phy(found, phy->port);
-		if (phy->port->num_phys == 0)
+		if (phy->port->num_phys == 0) {
 			list_add_tail(&phy->port->del_list,
 				&parent->port->sas_port_del_list);
+			if (ex_dev->parent_port == phy->port)
+				ex_dev->parent_port = NULL;
+		}
 		phy->port = NULL;
 	}
 }

drivers/scsi/libsas/sas_internal.h

@@ -189,21 +189,6 @@ static inline void sas_phy_set_target(struct asd_sas_phy *p, struct domain_devic
 	}
 }
 
-static inline void sas_add_parent_port(struct domain_device *dev, int phy_id)
-{
-	struct expander_device *ex = &dev->ex_dev;
-	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
-
-	if (!ex->parent_port) {
-		ex->parent_port = sas_port_alloc(&dev->rphy->dev, phy_id);
-		/* FIXME: error handling */
-		BUG_ON(!ex->parent_port);
-		BUG_ON(sas_port_add(ex->parent_port));
-		sas_port_mark_backlink(ex->parent_port);
-	}
-	sas_port_add_phy(ex->parent_port, ex_phy->phy);
-}
-
 static inline struct domain_device *sas_alloc_device(void)
 {
 	struct domain_device *dev = kzalloc(sizeof(*dev), GFP_KERNEL);