[PATCH AUTOSEL for 4.9 109/293] sfc: remove duplicate up_write on VF filter_sem

[Sasha Levin]

From: Edward Cree <ecree@xxxxxxxxxxxxxx>

[ Upstream commit 57f0c9cf58ff7fe479137ab847a886d0eed3ad1d ]

Somehow two copies of the line 'up_write(&vf->efx->filter_sem);' got into
 efx_ef10_sriov_set_vf_vlan().  This would put the mutex in a bad state and
 cause all subsequent down attempts to hang.

Fixes: 671b53eec2ed ("sfc: Ensure down_write(&filter_sem) and up_write() are matched before calling efx_net_open()")
Signed-off-by: Edward Cree <ecree@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
 drivers/net/ethernet/sfc/ef10_sriov.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/sfc/ef10_sriov.c b/drivers/net/ethernet/sfc/ef10_sriov.c
index a949b9d27329..d87d89d3c956 100644
--- a/drivers/net/ethernet/sfc/ef10_sriov.c
+++ b/drivers/net/ethernet/sfc/ef10_sriov.c
@@ -660,8 +660,6 @@ restore_filters:
 		up_write(&vf->efx->filter_sem);
 		mutex_unlock(&vf->efx->mac_lock);
 
-		up_write(&vf->efx->filter_sem);
-
 		rc2 = efx_net_open(vf->efx->net_dev);
 		if (rc2)
 			goto reset_nic;
-- 
2.15.1