[PATCH 4.19 56/79] ibmvnic: Do not process reset during or after device removal

From: Greg Kroah-Hartman
Date: Thu Sep 19 2019 - 18:31:54 EST


From: Thomas Falcon <tlfalcon@xxxxxxxxxxxxx>

[ Upstream commit 36f1031c51a2538e5558fb44c6d6b88f98d3c0f2 ]

Currently, the ibmvnic driver will not schedule device resets
if the device is being removed, but does not check the device
state before the reset is actually processed. This leads to a race
where a reset is scheduled with a valid device state but is
processed after the driver has been removed, resulting in an oops.

Fix this by checking the device state before processing a queued
reset event.

Reported-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
Tested-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Thomas Falcon <tlfalcon@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/ibm/ibmvnic.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 255de7d68cd33..5a57be66a4872 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1998,6 +1998,10 @@ static void __ibmvnic_reset(struct work_struct *work)

rwi = get_next_rwi(adapter);
while (rwi) {
+ if (adapter->state == VNIC_REMOVING ||
+ adapter->state == VNIC_REMOVED)
+ goto out;
+
if (adapter->force_reset_recovery) {
adapter->force_reset_recovery = false;
rc = do_hard_reset(adapter, rwi, reset_state);
@@ -2022,7 +2026,7 @@ static void __ibmvnic_reset(struct work_struct *work)
netdev_dbg(adapter->netdev, "Reset failed\n");
free_all_rwi(adapter);
}
-
+out:
adapter->resetting = false;
if (we_lock_rtnl)
rtnl_unlock();
--
2.20.1