From: Larysa Zaremba <[email protected]>

Add a ring_lock mutex to protect sections, where software rings are
affected. Particularly, to prevent system crash, when tx_timeout
and .ndo_bpf() happen at the same time.

Fixes: 2d4238f55697 ("ice: Add support for AF_XDP")
Signed-off-by: Larysa Zaremba <[email protected]>
---
 drivers/net/ethernet/intel/ice/ice.h      |  2 ++
 drivers/net/ethernet/intel/ice/ice_lib.c  | 23 ++++++++++---
 drivers/net/ethernet/intel/ice/ice_main.c | 39 ++++++++++++++++++++---
 drivers/net/ethernet/intel/ice/ice_xsk.c  | 13 ++------
 4 files changed, 57 insertions(+), 20 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice.h 
b/drivers/net/ethernet/intel/ice/ice.h
index 701a61d791dd..7c1e24afa34b 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -307,6 +307,7 @@ enum ice_pf_state {
        ICE_PHY_INIT_COMPLETE,
        ICE_FD_VF_FLUSH_CTX,            /* set at FD Rx IRQ or timeout */
        ICE_AUX_ERR_PENDING,
+       ICE_RTNL_WAITS_FOR_RESET,
        ICE_STATE_NBITS         /* must be last */
 };
 
@@ -941,6 +942,7 @@ int ice_prepare_xdp_rings(struct ice_vsi *vsi, struct 
bpf_prog *prog,
                          enum ice_xdp_cfg cfg_type);
 int ice_destroy_xdp_rings(struct ice_vsi *vsi, enum ice_xdp_cfg cfg_type);
 void ice_map_xdp_rings(struct ice_vsi *vsi);
+bool ice_rebuild_pending(struct ice_vsi *vsi);
 int
 ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
             u32 flags);
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c 
b/drivers/net/ethernet/intel/ice/ice_lib.c
index 7629b0190578..a5dc6fc6e63d 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -2426,7 +2426,10 @@ void ice_vsi_decfg(struct ice_vsi *vsi)
                dev_err(ice_pf_to_dev(pf), "Failed to remove RDMA scheduler 
config for VSI %u, err %d\n",
                        vsi->vsi_num, err);
 
-       if (ice_is_xdp_ena_vsi(vsi))
+       /* xdp_rings can be absent, if program was attached amid reset,
+        * VSI rebuild is supposed to create them later
+        */
+       if (ice_is_xdp_ena_vsi(vsi) && vsi->xdp_rings)
                /* return value check can be skipped here, it always returns
                 * 0 if reset is in progress
                 */
@@ -2737,12 +2740,24 @@ ice_queue_set_napi(struct ice_vsi *vsi, unsigned int 
queue_index,
        if (current_work() == &pf->serv_task ||
            test_bit(ICE_PREPARED_FOR_RESET, pf->state) ||
            test_bit(ICE_DOWN, pf->state) ||
-           test_bit(ICE_SUSPENDED, pf->state))
+           test_bit(ICE_SUSPENDED, pf->state)) {
+               bool rtnl_held_here = true;
+
+               while (!rtnl_trylock()) {
+                       if (test_bit(ICE_RTNL_WAITS_FOR_RESET, pf->state)) {
+                               rtnl_held_here = false;
+                               break;
+                       }
+                       usleep_range(1000, 2000);
+               }
                __ice_queue_set_napi(vsi->netdev, queue_index, type, napi,
-                                    false);
-       else
+                                    true);
+               if (rtnl_held_here)
+                       rtnl_unlock();
+       } else {
                __ice_queue_set_napi(vsi->netdev, queue_index, type, napi,
                                     true);
+       }
 }
 
 /**
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c 
b/drivers/net/ethernet/intel/ice/ice_main.c
index 15a6805ac2a1..7724ed8fc1b1 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2986,6 +2986,20 @@ static int ice_max_xdp_frame_size(struct ice_vsi *vsi)
                return ICE_RXBUF_3072;
 }
 
+/**
+ * ice_rebuild_pending - ice_vsi_rebuild will be performed, when locks are 
released
+ * @vsi: VSI to setup XDP for
+ *
+ * ice_vsi_close() in the reset path is called under rtnl_lock(),
+ * so it happened strictly before or after .ndo_bpf().
+ * In case it has happened before, we do not have anything attached to rings
+ */
+bool ice_rebuild_pending(struct ice_vsi *vsi)
+{
+       return ice_is_reset_in_progress(vsi->back->state) &&
+              !vsi->rx_rings[0]->desc;
+}
+
 /**
  * ice_xdp_setup_prog - Add or remove XDP eBPF program
  * @vsi: VSI to setup XDP for
@@ -3009,7 +3023,7 @@ ice_xdp_setup_prog(struct ice_vsi *vsi, struct bpf_prog 
*prog,
        }
 
        /* hot swap progs and avoid toggling link */
-       if (ice_is_xdp_ena_vsi(vsi) == !!prog) {
+       if (ice_is_xdp_ena_vsi(vsi) == !!prog || ice_rebuild_pending(vsi)) {
                ice_vsi_assign_bpf_prog(vsi, prog);
                return 0;
        }
@@ -3081,21 +3095,33 @@ static int ice_xdp(struct net_device *dev, struct 
netdev_bpf *xdp)
 {
        struct ice_netdev_priv *np = netdev_priv(dev);
        struct ice_vsi *vsi = np->vsi;
+       struct ice_pf *pf = vsi->back;
+       int ret;
 
        if (vsi->type != ICE_VSI_PF) {
                NL_SET_ERR_MSG_MOD(xdp->extack, "XDP can be loaded only on PF 
VSI");
                return -EINVAL;
        }
 
+       while (test_and_set_bit(ICE_CFG_BUSY, pf->state)) {
+               set_bit(ICE_RTNL_WAITS_FOR_RESET, pf->state);
+               usleep_range(1000, 2000);
+       }
+       clear_bit(ICE_RTNL_WAITS_FOR_RESET, pf->state);
+
        switch (xdp->command) {
        case XDP_SETUP_PROG:
-               return ice_xdp_setup_prog(vsi, xdp->prog, xdp->extack);
+               ret = ice_xdp_setup_prog(vsi, xdp->prog, xdp->extack);
+               break;
        case XDP_SETUP_XSK_POOL:
-               return ice_xsk_pool_setup(vsi, xdp->xsk.pool,
-                                         xdp->xsk.queue_id);
+               ret = ice_xsk_pool_setup(vsi, xdp->xsk.pool, xdp->xsk.queue_id);
+               break;
        default:
-               return -EINVAL;
+               ret = -EINVAL;
        }
+
+       clear_bit(ICE_CFG_BUSY, pf->state);
+       return ret;
 }
 
 /**
@@ -7672,7 +7698,10 @@ static void ice_rebuild(struct ice_pf *pf, enum 
ice_reset_req reset_type)
                ice_gnss_init(pf);
 
        /* rebuild PF VSI */
+       while (test_and_set_bit(ICE_CFG_BUSY, pf->state))
+               usleep_range(1000, 2000);
        err = ice_vsi_rebuild_by_type(pf, ICE_VSI_PF);
+       clear_bit(ICE_CFG_BUSY, pf->state);
        if (err) {
                dev_err(dev, "PF VSI rebuild failed: %d\n", err);
                goto err_vsi_rebuild;
diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c 
b/drivers/net/ethernet/intel/ice/ice_xsk.c
index 225d027d3d7a..962af14f9fd5 100644
--- a/drivers/net/ethernet/intel/ice/ice_xsk.c
+++ b/drivers/net/ethernet/intel/ice/ice_xsk.c
@@ -370,7 +370,6 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct 
xsk_buff_pool *pool, u16 qid)
 {
        bool if_running, pool_present = !!pool;
        int ret = 0, pool_failure = 0;
-       struct ice_pf *pf = vsi->back;
 
        if (qid >= vsi->num_rxq || qid >= vsi->num_txq) {
                netdev_err(vsi->netdev, "Please use queue id in scope of 
combined queues count\n");
@@ -378,18 +377,11 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct 
xsk_buff_pool *pool, u16 qid)
                goto failure;
        }
 
-       if_running = netif_running(vsi->netdev) && ice_is_xdp_ena_vsi(vsi);
+       if_running = !ice_rebuild_pending(vsi) &&
+                    (netif_running(vsi->netdev) && ice_is_xdp_ena_vsi(vsi));
 
        if (if_running) {
                struct ice_rx_ring *rx_ring = vsi->rx_rings[qid];
-               int timeout = 50;
-
-               while (test_and_set_bit(ICE_CFG_BUSY, pf->state)) {
-                       timeout--;
-                       if (!timeout)
-                               return -EBUSY;
-                       usleep_range(1000, 2000);
-               }
 
                ret = ice_qp_dis(vsi, qid);
                if (ret) {
@@ -412,7 +404,6 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct 
xsk_buff_pool *pool, u16 qid)
                        
napi_schedule(&vsi->rx_rings[qid]->xdp_ring->q_vector->napi);
                else if (ret)
                        netdev_err(vsi->netdev, "ice_qp_ena error = %d\n", ret);
-               clear_bit(ICE_CFG_BUSY, pf->state);
        }
 
 failure:
-- 
2.34.1

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