ibmvnic: device remove has higher precedence over reset

Returning -EBUSY in ibmvnic_remove() does not actually hold the
removal procedure since driver core doesn't care for the return
value (see __device_release_driver() in drivers/base/dd.c
calling dev->bus->remove()) though vio_bus_remove
(in arch/powerpc/platforms/pseries/vio.c) records the
return value and passes it on. [1]

During the device removal precedure, checking for resetting
bit is dropped so that we can continue executing all the
cleanup calls in the rest of the remove function. Otherwise,
it can cause latent memory leaks and kernel crashes.

[1] https://lore.kernel.org/linuxppc-dev/20210117101242.dpwayq6wdgfdzirl@pengutronix.de/T/#m48f5befd96bc9842ece2a3ad14f4c27747206a53
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 7d7195a026ba ("ibmvnic: Do not process device remove during device reset")
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Link: https://lore.kernel.org/r/20210129043402.95744-1-ljp@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 8820c98ea891e39bb921348ec51c4919fc1e641f..f79034c786c847427fbf8bc9ad6921049a9d84e7 100644 (file)
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5444,11 +5444,6 @@ static int ibmvnic_remove(struct vio_dev *dev)
        unsigned long flags;
 
        spin_lock_irqsave(&adapter->state_lock, flags);
-       if (test_bit(0, &adapter->resetting)) {
-               spin_unlock_irqrestore(&adapter->state_lock, flags);
-               return -EBUSY;
-       }
-
        adapter->state = VNIC_REMOVING;
        spin_unlock_irqrestore(&adapter->state_lock, flags);