cxgb4: fix IRQ free race during driver unload

IRQs are requested during driver's ndo_open() and then later
freed up in disable_interrupts() during driver unload.
A race exists where driver can set the CXGB4_FULL_INIT_DONE
flag in ndo_open() after the disable_interrupts() in driver
unload path checks it, and hence misses calling free_irq().

Fix by unregistering netdevice first and sync with driver's
ndo_open(). This ensures disable_interrupts() checks the flag
correctly and frees up the IRQs properly.

Fixes: b37987e8db5f ("cxgb4: Disable interrupts and napi before unregistering netdev")
Signed-off-by: Shahjada Abul Husain <shahjada@chelsio.com>
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index 9a2b166..dbf9a0e 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -2643,6 +2643,9 @@ static void detach_ulds(struct adapter *adap)
 {
        unsigned int i;
 
+       if (!is_uld(adap))
+               return;
+
        mutex_lock(&uld_mutex);
        list_del(&adap->list_node);
 
@@ -7141,10 +7144,13 @@ static void remove_one(struct pci_dev *pdev)
                 */
                destroy_workqueue(adapter->workq);
 
-               if (is_uld(adapter)) {
-                       detach_ulds(adapter);
-                       t4_uld_clean_up(adapter);
-               }
+               detach_ulds(adapter);
+
+               for_each_port(adapter, i)
+                       if (adapter->port[i]->reg_state == NETREG_REGISTERED)
+                               unregister_netdev(adapter->port[i]);
+
+               t4_uld_clean_up(adapter);
 
                adap_free_hma_mem(adapter);
 
@@ -7152,10 +7158,6 @@ static void remove_one(struct pci_dev *pdev)
 
                cxgb4_free_mps_ref_entries(adapter);
 
-               for_each_port(adapter, i)
-                       if (adapter->port[i]->reg_state == NETREG_REGISTERED)
-                               unregister_netdev(adapter->port[i]);
-
                debugfs_remove_recursive(adapter->debugfs_root);
 
                if (!is_t4(adapter->params.chip))

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
index 743af9e..17faac7 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
@@ -581,6 +581,9 @@ void t4_uld_clean_up(struct adapter *adap)
 {
        unsigned int i;
 
+       if (!is_uld(adap))
+               return;
+
        mutex_lock(&uld_mutex);
        for (i = 0; i < CXGB4_ULD_MAX; i++) {
                if (!adap->uld[i].handle)