powerpc/eeh: Drop taken reference to driver on eeh_rmv_device

Commit f5c57710dd62dd06f176934a8b4b8accbf00f9f8 ("powerpc/eeh: Use
partial hotplug for EEH unaware drivers") introduces eeh_rmv_device,
which may grab a reference to a driver, but not release it.

That prevents a driver from being removed after it has gone through EEH
recovery.

This patch drops the reference if it was taken.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c
index 7bb30dca4e19..fdc679d309ec 100644
--- a/arch/powerpc/kernel/eeh_driver.c
+++ b/arch/powerpc/kernel/eeh_driver.c
@@ -362,9 +362,13 @@ static void *eeh_rmv_device(void *data, void *userdata)
          */
         if (!dev || (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE))
                 return NULL;
+
         driver = eeh_pcid_get(dev);
-        if (driver && driver->err_handler)
-                return NULL;
+        if (driver) {
+                eeh_pcid_put(dev);
+                if (driver->err_handler)
+                        return NULL;
+        }
 
         /* Remove it from PCI subsystem */
         pr_debug("EEH: Removing %s without EEH sensitive driver\n",