From 56f86e092f997770791f08e1ce0cbb473c29f42e Mon Sep 17 00:00:00 2001
From: Dave Ertman <david.m.ertman@intel.com>
Date: Thu, 20 Jan 2022 16:27:56 -0800
Subject: [PATCH 7/9] ice: Avoid RTNL lock when re-creating auxiliary device
Patch-mainline: v5.17-rc4
Git-commit: 5dbbbd01cbba831233c6ea9a3e6bfa133606d3c0
References: git-fixes

If a call to re-create the auxiliary device happens in a context that has
already taken the RTNL lock, then the call flow that recreates auxiliary
device can hang if there is another attempt to claim the RTNL lock by the
auxiliary driver.

To avoid this, any call to re-create auxiliary devices that comes from
an source that is holding the RTNL lock (e.g. netdev notifier when
interface exits a bond) should execute in a separate thread.  To
accomplish this, add a flag to the PF that will be evaluated in the
service task and dealt with there.

Fixes: f9f5301e7e2d ("ice: Register auxiliary device to provide RDMA")
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Reviewed-by: Jonathan Toppins <jtoppins@redhat.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/intel/ice/ice.h      | 3 ++-
 drivers/net/ethernet/intel/ice/ice_main.c | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index 9dc39206129f..a2d7d7ab8444 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -483,6 +483,7 @@ enum ice_pf_flags {
 	ICE_FLAG_VF_TRUE_PROMISC_ENA,
 	ICE_FLAG_MDD_AUTO_RESET_VF,
 	ICE_FLAG_LINK_LENIENT_MODE_ENA,
+	ICE_FLAG_PLUG_AUX_DEV,
 	ICE_PF_FLAGS_NBITS		/* must be last */
 };
 
@@ -883,7 +884,7 @@ 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);
+		set_bit(ICE_FLAG_PLUG_AUX_DEV, pf->flags);
 	}
 }
 
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index e695c3e78cc2..0c70d6127fe3 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2237,6 +2237,9 @@ static void ice_service_task(struct work_struct *work)
 		return;
 	}
 
+	if (test_and_clear_bit(ICE_FLAG_PLUG_AUX_DEV, pf->flags))
+		ice_plug_aux_dev(pf);
+
 	ice_clean_adminq_subtask(pf);
 	ice_check_media_subtask(pf);
 	ice_check_for_hang_subtask(pf);
-- 
2.16.4