[PATCH] ice: Fix wrong dsn read in ice_adapter_put

[Cyrill Gorcunov <gorcunov@gmail.com>]

When registering an adapter instance, we read the PCI configuration
space to fetch the DSN and generate an adapter index for lookups.

However, if the adapter has been physically unplugged, the PCI space
is no longer accessible. Reading it returns a zero value, which results
in either an incorrect adapter instance being put or the proper instance
not being put at all. To fix this, we will use the previously known
index instead.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
---
 drivers/net/ethernet/intel/ice/ice_adapter.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Index: linux-tip.git/drivers/net/ethernet/intel/ice/ice_adapter.c
===================================================================
--- linux-tip.git.orig/drivers/net/ethernet/intel/ice/ice_adapter.c
+++ linux-tip.git/drivers/net/ethernet/intel/ice/ice_adapter.c
@@ -130,13 +130,13 @@ struct ice_adapter *ice_adapter_get(stru
  */
 void ice_adapter_put(struct pci_dev *pdev)
 {
+	const struct ice_pf *pf = pci_get_drvdata(pdev);
+	unsigned long index = pf->adapter->index;
 	struct ice_adapter *adapter;
-	unsigned long index;
 
-	index = ice_adapter_xa_index(pdev);
 	scoped_guard(mutex, &ice_adapters_mutex) {
 		adapter = xa_load(&ice_adapters, index);
-		if (WARN_ON(!adapter))
+		if (WARN_ON(!adapter || adapter != pf->adapter))
 			return;
 		if (!refcount_dec_and_test(&adapter->refcount))
 			return;