[PATCH net] ice: Correctly deal with PFs that do not support RDMA

[Dave Ertman]

There are two cases where the current PF does not support RDMA
functionality.  The first is if the NVM loaded on the device is set
to not support RDMA (common_caps.rdma is false).  The second is if
the kernel bonding driver has included the current PF in an active
link aggregate.

When the driver has determined that this PF does not support RDMA, then
auxiliary devices should not be created on the auxiliary bus.  Without
a device on the auxiliary bus, even if the irdma driver is present, there
will be no RDMA activity attempted on this PF.

Currently, in the reset flow, an attempt to create auxiliary devices is
performed without regard to the ability of the PF.  There needs to be a
check in ice_aux_plug_dev (as the central point that creates auxiliary
devices) to see if the PF is in a state to support the functionality.

When disabling and re-enabling RDMA due to the inclusion/removal of the PF
in a link aggregate, we also need to set/clear the bit which controls
auxiliary device creation so that a reset recovery in a link aggregate
situation doesn't try to create auxiliary devices when it shouldn't.

Fixes: f9f5301e7e2d ("ice: Register auxiliary device to provide RDMA")
Reported-by: Yongxin Liu <yongxin.liu@xxxxxxxxxxxxx>
Signed-off-by: Dave Ertman <david.m.ertman@xxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
---
 drivers/net/ethernet/intel/ice/ice.h     | 2 ++
 drivers/net/ethernet/intel/ice/ice_idc.c | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index eadcb9958346..3c4f08d20414 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -695,6 +695,7 @@ static inline void ice_set_rdma_cap(struct ice_pf *pf)
 {
 	if (pf->hw.func_caps.common_cap.rdma && pf->num_rdma_msix) {
 		set_bit(ICE_FLAG_RDMA_ENA, pf->flags);
+		set_bit(ICE_FLAG_AUX_ENA, pf->flags);
 		ice_plug_aux_dev(pf);
 	}
 }
@@ -707,5 +708,6 @@ static inline void ice_clear_rdma_cap(struct ice_pf *pf)
 {
 	ice_unplug_aux_dev(pf);
 	clear_bit(ICE_FLAG_RDMA_ENA, pf->flags);
+	clear_bit(ICE_FLAG_AUX_ENA, pf->flags);
 }
 #endif /* _ICE_H_ */
diff --git a/drivers/net/ethernet/intel/ice/ice_idc.c b/drivers/net/ethernet/intel/ice/ice_idc.c
index 1f2afdf6cd48..adcc9a251595 100644
--- a/drivers/net/ethernet/intel/ice/ice_idc.c
+++ b/drivers/net/ethernet/intel/ice/ice_idc.c
@@ -271,6 +271,12 @@ int ice_plug_aux_dev(struct ice_pf *pf)
 	struct auxiliary_device *adev;
 	int ret;
 
+	/* if this PF doesn't support a technology that requires auxiliary
+	 * devices, then gracefully exit
+	 */
+	if (!ice_is_aux_ena(pf))
+		return 0;
+
 	iadev = kzalloc(sizeof(*iadev), GFP_KERNEL);
 	if (!iadev)
 		return -ENOMEM;
-- 
2.31.1