Hi, I haven't reviewed this patch in its entirety, but I'm pretty sure you're introducing a reliable AA deadlock. See below.
Are you sure you're actually testing these codepaths? On Tue, Oct 31, 2017 at 03:12:47PM +0530, Ganapathi Bhat wrote: > From: Karthik Ananthapadmanabha <[email protected]> > > Fix the incorrect usage of rx_reorder_tbl_lock spinlock: > > 1. We shouldn't access the fields of the elements returned by > mwifiex_11n_get_rx_reorder_tbl() after we have released spin > lock. To fix this, To fix this, aquire the spinlock before > calling this function and release the lock only after processing > the corresponding element is complete. > > 2. Realsing the spinlock during iteration of the list and holding > it back before next iteration is unsafe. Fix it by releasing the > lock only after iteration of the list is complete. > > Signed-off-by: Karthik Ananthapadmanabha <[email protected]> > Signed-off-by: Ganapathi Bhat <[email protected]> > --- > .../net/wireless/marvell/mwifiex/11n_rxreorder.c | 34 > +++++++++++++++++----- > drivers/net/wireless/marvell/mwifiex/uap_txrx.c | 3 ++ > 2 files changed, 29 insertions(+), 8 deletions(-) > > diff --git a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c > b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c > index 4631bc2..b99ace8 100644 > --- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c > +++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c > @@ -234,23 +234,19 @@ static int mwifiex_11n_dispatch_pkt(struct > mwifiex_private *priv, void *payload) > > /* > * This function returns the pointer to an entry in Rx reordering > - * table which matches the given TA/TID pair. > + * table which matches the given TA/TID pair. The caller must > + * hold rx_reorder_tbl_lock, before calling this function. > */ > struct mwifiex_rx_reorder_tbl * > mwifiex_11n_get_rx_reorder_tbl(struct mwifiex_private *priv, int tid, u8 *ta) > { > struct mwifiex_rx_reorder_tbl *tbl; > - unsigned long flags; > > - spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > list_for_each_entry(tbl, &priv->rx_reorder_tbl_ptr, list) { > if (!memcmp(tbl->ta, ta, ETH_ALEN) && tbl->tid == tid) { > - spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, > - flags); > return tbl; > } > } > - spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > > return NULL; > } > @@ -355,11 +351,14 @@ void mwifiex_11n_del_rx_reorder_tbl_by_ta(struct > mwifiex_private *priv, u8 *ta) > * If we get a TID, ta pair which is already present dispatch all the > * the packets and move the window size until the ssn > */ > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, ta); > if (tbl) { > mwifiex_11n_dispatch_pkt_until_start_win(priv, tbl, seq_num); > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > return; > } > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > /* if !tbl then create one */ > new_node = kzalloc(sizeof(struct mwifiex_rx_reorder_tbl), GFP_KERNEL); > if (!new_node) > @@ -571,15 +570,19 @@ int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private > *priv, > u16 pkt_index; > bool init_window_shift = false; > int ret = 0; > + unsigned long flags; > > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, ta); > if (!tbl) { > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > if (pkt_type != PKT_TYPE_BAR) > mwifiex_11n_dispatch_pkt(priv, payload); > return ret; > } > > if ((pkt_type == PKT_TYPE_AMSDU) && !tbl->amsdu) { > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > mwifiex_11n_dispatch_pkt(priv, payload); > return ret; > } > @@ -666,6 +669,8 @@ int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private > *priv, > if (!tbl->timer_context.timer_is_set || > prev_start_win != tbl->start_win) > mwifiex_11n_rxreorder_timer_restart(tbl); > + > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > return ret; > } > > @@ -683,6 +688,7 @@ int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private > *priv, > struct mwifiex_ra_list_tbl *ra_list; > u8 cleanup_rx_reorder_tbl; > int tid_down; > + unsigned long flags; > > if (type == TYPE_DELBA_RECEIVE) > cleanup_rx_reorder_tbl = (initiator) ? true : false; > @@ -693,14 +699,18 @@ int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private > *priv, > peer_mac, tid, initiator); > > if (cleanup_rx_reorder_tbl) { > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, > peer_mac); > if (!tbl) { > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, > + flags); > mwifiex_dbg(priv->adapter, EVENT, > "event: TID, TA not found in table\n"); > return; > } > mwifiex_del_rx_reorder_entry(priv, tbl); > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > } else { > ptx_tbl = mwifiex_get_ba_tbl(priv, tid, peer_mac); > if (!ptx_tbl) { > @@ -732,6 +742,7 @@ int mwifiex_ret_11n_addba_resp(struct mwifiex_private > *priv, > int tid, win_size; > struct mwifiex_rx_reorder_tbl *tbl; > uint16_t block_ack_param_set; > + unsigned long flags; > > block_ack_param_set = le16_to_cpu(add_ba_rsp->block_ack_param_set); > > @@ -745,17 +756,20 @@ int mwifiex_ret_11n_addba_resp(struct mwifiex_private > *priv, > mwifiex_dbg(priv->adapter, ERROR, "ADDBA RSP: failed %pM > tid=%d)\n", > add_ba_rsp->peer_mac_addr, tid); > > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, > add_ba_rsp->peer_mac_addr); > if (tbl) > mwifiex_del_rx_reorder_entry(priv, tbl); > > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > return 0; > } > > win_size = (block_ack_param_set & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) > >> BLOCKACKPARAM_WINSIZE_POS; > > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, > add_ba_rsp->peer_mac_addr); > if (tbl) { > @@ -766,6 +780,7 @@ int mwifiex_ret_11n_addba_resp(struct mwifiex_private > *priv, > else > tbl->amsdu = false; > } > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > > mwifiex_dbg(priv->adapter, CMD, > "cmd: ADDBA RSP: %pM tid=%d ssn=%d win_size=%d\n", > @@ -806,9 +821,7 @@ void mwifiex_11n_cleanup_reorder_tbl(struct > mwifiex_private *priv) > spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); ^^ Acquisition > list_for_each_entry_safe(del_tbl_ptr, tmp_node, > &priv->rx_reorder_tbl_ptr, list) { > - spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); ^^ No longer dropping the lock > mwifiex_del_rx_reorder_entry(priv, del_tbl_ptr); ^^ This function also acquires the lock Deadlock! Brian > - spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > } > INIT_LIST_HEAD(&priv->rx_reorder_tbl_ptr); > spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > @@ -933,6 +946,7 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private > *priv, > int tlv_buf_left = len; > int ret; > u8 *tmp; > + unsigned long flags; > > mwifiex_dbg_dump(priv->adapter, EVT_D, "RXBA_SYNC event:", > event_buf, len); > @@ -952,14 +966,18 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private > *priv, > tlv_rxba->mac, tlv_rxba->tid, tlv_seq_num, > tlv_bitmap_len); > > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > rx_reor_tbl_ptr = > mwifiex_11n_get_rx_reorder_tbl(priv, tlv_rxba->tid, > tlv_rxba->mac); > if (!rx_reor_tbl_ptr) { > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, > + flags); > mwifiex_dbg(priv->adapter, ERROR, > "Can not find rx_reorder_tbl!"); > return; > } > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > > for (i = 0; i < tlv_bitmap_len; i++) { > for (j = 0 ; j < 8; j++) { > diff --git a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c > b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c > index 1e6a62c..21dc14f 100644 > --- a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c > +++ b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c > @@ -421,12 +421,15 @@ int mwifiex_process_uap_rx_packet(struct > mwifiex_private *priv, > spin_unlock_irqrestore(&priv->sta_list_spinlock, flags); > } > > + spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags); > if (!priv->ap_11n_enabled || > (!mwifiex_11n_get_rx_reorder_tbl(priv, uap_rx_pd->priority, ta) && > (le16_to_cpu(uap_rx_pd->rx_pkt_type) != PKT_TYPE_AMSDU))) { > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > ret = mwifiex_handle_uap_rx_forward(priv, skb); > return ret; > } > + spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags); > > /* Reorder and send to kernel */ > pkt_type = (u8)le16_to_cpu(uap_rx_pd->rx_pkt_type); > -- > 1.9.1 >
