From: Yanguo Li yanguo.li@corigine.com

When there are CT table entries, and you rmmod nfp, the following events can happen:

task1： nfp_net_pci_remove ↓ nfp_flower_stop->(asynchronous)tcf_ct_flow_table_cleanup_work(3) ↓ nfp_zone_table_entry_destroy(1)

task2： nfp_fl_ct_handle_nft_flow(2)

When the execution order is (1)->(2)->(3), it will crash. Therefore, in the function nfp_fl_ct_del_flow, nf_flow_table_offload_del_cb needs to be executed synchronously.

At the same time, in order to solve the deadlock problem and the problem of rtnl_lock sometimes failing, replace rtnl_lock with the private nfp_fl_lock.

Fixes: 7cc93d888df7 ("nfp: flower-ct: remove callback delete deadlock") Cc: stable@vger.kernel.org Signed-off-by: Yanguo Li yanguo.li@corigine.com Signed-off-by: Louis Peens louis.peens@corigine.com --- .../net/ethernet/netronome/nfp/flower/cmsg.c | 10 ++++---- .../ethernet/netronome/nfp/flower/conntrack.c | 19 ++++++++++----- .../net/ethernet/netronome/nfp/flower/main.h | 2 ++ .../ethernet/netronome/nfp/flower/metadata.c | 2 ++ .../ethernet/netronome/nfp/flower/offload.c | 24 ++++++++++++++----- .../ethernet/netronome/nfp/flower/qos_conf.c | 20 ++++++++++------ 6 files changed, 54 insertions(+), 23 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c index f21cf1f40f98..153533cd8f08 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c +++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c @@ -210,6 +210,7 @@ nfp_flower_cmsg_merge_hint_rx(struct nfp_app *app, struct sk_buff *skb) unsigned int msg_len = nfp_flower_cmsg_get_data_len(skb); struct nfp_flower_cmsg_merge_hint *msg; struct nfp_fl_payload *sub_flows[2]; + struct nfp_flower_priv *priv; int err, i, flow_cnt;

msg = nfp_flower_cmsg_get_data(skb); @@ -228,14 +229,15 @@ nfp_flower_cmsg_merge_hint_rx(struct nfp_app *app, struct sk_buff *skb) return; }

- rtnl_lock(); + priv = app->priv; + mutex_lock(&priv->nfp_fl_lock); for (i = 0; i < flow_cnt; i++) { u32 ctx = be32_to_cpu(msg->flow[i].host_ctx);

sub_flows[i] = nfp_flower_get_fl_payload_from_ctx(app, ctx); if (!sub_flows[i]) { nfp_flower_cmsg_warn(app, "Invalid flow in merge hint\n"); - goto err_rtnl_unlock; + goto err_mutex_unlock; } }

@@ -244,8 +246,8 @@ nfp_flower_cmsg_merge_hint_rx(struct nfp_app *app, struct sk_buff *skb) if (err == -ENOMEM) nfp_flower_cmsg_warn(app, "Flow merge memory fail.\n");

-err_rtnl_unlock: - rtnl_unlock(); +err_mutex_unlock: + mutex_unlock(&priv->nfp_fl_lock); }

static void diff --git a/drivers/net/ethernet/netronome/nfp/flower/conntrack.c b/drivers/net/ethernet/netronome/nfp/flower/conntrack.c index 2643c4b3ff1f..2967bab72505 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/conntrack.c +++ b/drivers/net/ethernet/netronome/nfp/flower/conntrack.c @@ -2131,8 +2131,6 @@ nfp_fl_ct_offload_nft_flow(struct nfp_fl_ct_zone_entry *zt, struct flow_cls_offl struct nfp_fl_ct_flow_entry *ct_entry; struct netlink_ext_ack *extack = NULL;

- ASSERT_RTNL(); - extack = flow->common.extack; switch (flow->command) { case FLOW_CLS_REPLACE: @@ -2178,9 +2176,13 @@ int nfp_fl_ct_handle_nft_flow(enum tc_setup_type type, void *type_data, void *cb

switch (type) { case TC_SETUP_CLSFLOWER: - rtnl_lock(); + while (!mutex_trylock(&zt->priv->nfp_fl_lock)) { + if (!zt->nft) /* avoid deadlock */ + return err; + msleep(20); + } err = nfp_fl_ct_offload_nft_flow(zt, flow); - rtnl_unlock(); + mutex_unlock(&zt->priv->nfp_fl_lock); break; default: return -EOPNOTSUPP; @@ -2208,6 +2210,7 @@ int nfp_fl_ct_del_flow(struct nfp_fl_ct_map_entry *ct_map_ent) struct nfp_fl_ct_flow_entry *ct_entry; struct nfp_fl_ct_zone_entry *zt; struct rhashtable *m_table; + struct nf_flowtable *nft;

if (!ct_map_ent) return -ENOENT; @@ -2226,8 +2229,12 @@ int nfp_fl_ct_del_flow(struct nfp_fl_ct_map_entry *ct_map_ent) if (ct_map_ent->cookie > 0) kfree(ct_map_ent);

- if (!zt->pre_ct_count) { - zt->nft = NULL; + if (!zt->pre_ct_count && zt->nft) { + nft = zt->nft; + zt->nft = NULL; /* avoid deadlock */ + nf_flow_table_offload_del_cb(nft, + nfp_fl_ct_handle_nft_flow, + zt); nfp_fl_ct_clean_nft_entries(zt); } break; diff --git a/drivers/net/ethernet/netronome/nfp/flower/main.h b/drivers/net/ethernet/netronome/nfp/flower/main.h index 40372545148e..2b7c947ff4f2 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/main.h +++ b/drivers/net/ethernet/netronome/nfp/flower/main.h @@ -297,6 +297,7 @@ struct nfp_fl_internal_ports { * @predt_list: List to keep track of decap pretun flows * @neigh_table: Table to keep track of neighbor entries * @predt_lock: Lock to serialise predt/neigh table updates + * @nfp_fl_lock: Lock to protect the flow offload operation */ struct nfp_flower_priv { struct nfp_app *app; @@ -339,6 +340,7 @@ struct nfp_flower_priv { struct list_head predt_list; struct rhashtable neigh_table; spinlock_t predt_lock; /* Lock to serialise predt/neigh table updates */ + struct mutex nfp_fl_lock; /* Protect the flow operation */ };

/** diff --git a/drivers/net/ethernet/netronome/nfp/flower/metadata.c b/drivers/net/ethernet/netronome/nfp/flower/metadata.c index 0f06ef6e24bf..80e4675582bf 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/metadata.c +++ b/drivers/net/ethernet/netronome/nfp/flower/metadata.c @@ -528,6 +528,8 @@ int nfp_flower_metadata_init(struct nfp_app *app, u64 host_ctx_count, if (err) goto err_free_stats_ctx_table;

+ mutex_init(&priv->nfp_fl_lock); + err = rhashtable_init(&priv->ct_zone_table, &nfp_zone_table_params); if (err) goto err_free_merge_table; diff --git a/drivers/net/ethernet/netronome/nfp/flower/offload.c b/drivers/net/ethernet/netronome/nfp/flower/offload.c index c153f0575b92..0aceef9fe582 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/offload.c +++ b/drivers/net/ethernet/netronome/nfp/flower/offload.c @@ -1009,8 +1009,6 @@ int nfp_flower_merge_offloaded_flows(struct nfp_app *app, u64 parent_ctx = 0; int err;

- ASSERT_RTNL(); - if (sub_flow1 == sub_flow2 || nfp_flower_is_merge_flow(sub_flow1) || nfp_flower_is_merge_flow(sub_flow2)) @@ -1727,19 +1725,30 @@ static int nfp_flower_repr_offload(struct nfp_app *app, struct net_device *netdev, struct flow_cls_offload *flower) { + struct nfp_flower_priv *priv = app->priv; + int ret; + if (!eth_proto_is_802_3(flower->common.protocol)) return -EOPNOTSUPP;

+ mutex_lock(&priv->nfp_fl_lock); switch (flower->command) { case FLOW_CLS_REPLACE: - return nfp_flower_add_offload(app, netdev, flower); + ret = nfp_flower_add_offload(app, netdev, flower); + break; case FLOW_CLS_DESTROY: - return nfp_flower_del_offload(app, netdev, flower); + ret = nfp_flower_del_offload(app, netdev, flower); + break; case FLOW_CLS_STATS: - return nfp_flower_get_stats(app, netdev, flower); + ret = nfp_flower_get_stats(app, netdev, flower); + break; default: - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + break; } + mutex_unlock(&priv->nfp_fl_lock); + + return ret; }

static int nfp_flower_setup_tc_block_cb(enum tc_setup_type type, @@ -1778,6 +1787,7 @@ static int nfp_flower_setup_tc_block(struct net_device *netdev, repr_priv = repr->app_priv; repr_priv->block_shared = f->block_shared; f->driver_block_list = &nfp_block_cb_list; + f->unlocked_driver_cb = true;

switch (f->command) { case FLOW_BLOCK_BIND: @@ -1876,6 +1886,8 @@ nfp_flower_setup_indr_tc_block(struct net_device *netdev, struct Qdisc *sch, str nfp_flower_internal_port_can_offload(app, netdev))) return -EOPNOTSUPP;

+ f->unlocked_driver_cb = true; + switch (f->command) { case FLOW_BLOCK_BIND: cb_priv = nfp_flower_indr_block_cb_priv_lookup(app, netdev); diff --git a/drivers/net/ethernet/netronome/nfp/flower/qos_conf.c b/drivers/net/ethernet/netronome/nfp/flower/qos_conf.c index 99052a925d9e..e7180b4793c7 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/qos_conf.c +++ b/drivers/net/ethernet/netronome/nfp/flower/qos_conf.c @@ -523,25 +523,31 @@ int nfp_flower_setup_qos_offload(struct nfp_app *app, struct net_device *netdev, { struct netlink_ext_ack *extack = flow->common.extack; struct nfp_flower_priv *fl_priv = app->priv; + int ret;

if (!(fl_priv->flower_ext_feats & NFP_FL_FEATS_VF_RLIM)) { NL_SET_ERR_MSG_MOD(extack, "unsupported offload: loaded firmware does not support qos rate limit offload"); return -EOPNOTSUPP; }

+ mutex_lock(&fl_priv->nfp_fl_lock); switch (flow->command) { case TC_CLSMATCHALL_REPLACE: - return nfp_flower_install_rate_limiter(app, netdev, flow, - extack); + ret = nfp_flower_install_rate_limiter(app, netdev, flow, extack); + break; case TC_CLSMATCHALL_DESTROY: - return nfp_flower_remove_rate_limiter(app, netdev, flow, - extack); + ret = nfp_flower_remove_rate_limiter(app, netdev, flow, extack); + break; case TC_CLSMATCHALL_STATS: - return nfp_flower_stats_rate_limiter(app, netdev, flow, - extack); + ret = nfp_flower_stats_rate_limiter(app, netdev, flow, extack); + break; default: - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + break; } + mutex_unlock(&fl_priv->nfp_fl_lock); + + return ret; }

/* Offload tc action, currently only for tc police */