[4.20 PATCH] Revert "mwifiex: restructure rx_reorder_tbl_lock usage"

From: Brian Norris
Date: Fri Nov 30 2018 - 13:00:12 EST

This reverts commit 5188d5453bc9380ccd4ae1086138dd485d13aef2, because it
introduced lock recursion:

BUG: spinlock recursion on CPU#2, kworker/u13:1/395
lock: 0xffffffc0e28a47f0, .magic: dead4ead, .owner: kworker/u13:1/395, .owner_cpu: 2
CPU: 2 PID: 395 Comm: kworker/u13:1 Not tainted 4.20.0-rc4+ #2
Hardware name: Google Kevin (DT)
Workqueue: MWIFIEX_RX_WORK_QUEUE mwifiex_rx_work_queue [mwifiex]
Call trace:
dump_backtrace+0x0/0x140
show_stack+0x20/0x28
dump_stack+0x84/0xa4
spin_bug+0x98/0xa4
do_raw_spin_lock+0x5c/0xdc
_raw_spin_lock_irqsave+0x38/0x48
mwifiex_flush_data+0x2c/0xa4 [mwifiex]
call_timer_fn+0xcc/0x1c4
run_timer_softirq+0x264/0x4f0
__do_softirq+0x1a8/0x35c
do_softirq+0x54/0x64
netif_rx_ni+0xe8/0x120
mwifiex_recv_packet+0xfc/0x10c [mwifiex]
mwifiex_process_rx_packet+0x1d4/0x238 [mwifiex]
mwifiex_11n_dispatch_pkt+0x190/0x1ac [mwifiex]
mwifiex_11n_rx_reorder_pkt+0x28c/0x354 [mwifiex]
mwifiex_process_sta_rx_packet+0x204/0x26c [mwifiex]
mwifiex_handle_rx_packet+0x15c/0x16c [mwifiex]
mwifiex_rx_work_queue+0x104/0x134 [mwifiex]
worker_thread+0x4cc/0x72c
kthread+0x134/0x13c
ret_from_fork+0x10/0x18

This was clearly not tested well at all. I simply performed 'wget' in a
loop and it fell over within a few seconds.

Fixes: 5188d5453bc9 ("mwifiex: restructure rx_reorder_tbl_lock usage")
Cc: <stable@xxxxxxxxxxxxxxx>
Cc: Ganapathi Bhat <gbhat@xxxxxxxxxxx>
Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
---
This is a 4.19 regression, but IMO the revert should be merged ASAP.

drivers/net/wireless/marvell/mwifiex/11n.c | 5 +-
.../wireless/marvell/mwifiex/11n_rxreorder.c | 96 ++++++++++---------
.../net/wireless/marvell/mwifiex/uap_txrx.c | 3 -
3 files changed, 51 insertions(+), 53 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/11n.c b/drivers/net/wireless/marvell/mwifiex/11n.c
index e2addd8b878b..5d75c971004b 100644
--- a/drivers/net/wireless/marvell/mwifiex/11n.c
+++ b/drivers/net/wireless/marvell/mwifiex/11n.c
@@ -696,11 +696,10 @@ void mwifiex_11n_delba(struct mwifiex_private *priv, int tid)
"Send delba to tid=%d, %pM\n",
tid, rx_reor_tbl_ptr->ta);
mwifiex_send_delba(priv, tid, rx_reor_tbl_ptr->ta, 0);
- spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock,
- flags);
- return;
+ goto exit;
}
}
+exit:
spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
}

diff --git a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
index 8e63d14c1e1c..5380fba652cc 100644
--- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
+++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
@@ -103,8 +103,6 @@ static int mwifiex_11n_dispatch_pkt(struct mwifiex_private *priv, void *payload)
* There could be holes in the buffer, which are skipped by the function.
* Since the buffer is linear, the function uses rotation to simulate
* circular buffer.
- *
- * The caller must hold rx_reorder_tbl_lock spinlock.
*/
static void
mwifiex_11n_dispatch_pkt_until_start_win(struct mwifiex_private *priv,
@@ -113,21 +111,25 @@ mwifiex_11n_dispatch_pkt_until_start_win(struct mwifiex_private *priv,
{
int pkt_to_send, i;
void *rx_tmp_ptr;
+ unsigned long flags;

pkt_to_send = (start_win > tbl->start_win) ?
min((start_win - tbl->start_win), tbl->win_size) :
tbl->win_size;

for (i = 0; i < pkt_to_send; ++i) {
+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
rx_tmp_ptr = NULL;
if (tbl->rx_reorder_ptr[i]) {
rx_tmp_ptr = tbl->rx_reorder_ptr[i];
tbl->rx_reorder_ptr[i] = NULL;
}
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
if (rx_tmp_ptr)
mwifiex_11n_dispatch_pkt(priv, rx_tmp_ptr);
}

+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
/*
* We don't have a circular buffer, hence use rotation to simulate
* circular buffer
@@ -138,6 +140,7 @@ mwifiex_11n_dispatch_pkt_until_start_win(struct mwifiex_private *priv,
}

tbl->start_win = start_win;
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
}

/*
@@ -147,8 +150,6 @@ mwifiex_11n_dispatch_pkt_until_start_win(struct mwifiex_private *priv,
* The start window is adjusted automatically when a hole is located.
* Since the buffer is linear, the function uses rotation to simulate
* circular buffer.
- *
- * The caller must hold rx_reorder_tbl_lock spinlock.
*/
static void
mwifiex_11n_scan_and_dispatch(struct mwifiex_private *priv,
@@ -156,15 +157,22 @@ mwifiex_11n_scan_and_dispatch(struct mwifiex_private *priv,
{
int i, j, xchg;
void *rx_tmp_ptr;
+ unsigned long flags;

for (i = 0; i < tbl->win_size; ++i) {
- if (!tbl->rx_reorder_ptr[i])
+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
+ if (!tbl->rx_reorder_ptr[i]) {
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock,
+ flags);
break;
+ }
rx_tmp_ptr = tbl->rx_reorder_ptr[i];
tbl->rx_reorder_ptr[i] = NULL;
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
mwifiex_11n_dispatch_pkt(priv, rx_tmp_ptr);
}

+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
/*
* We don't have a circular buffer, hence use rotation to simulate
* circular buffer
@@ -177,6 +185,7 @@ mwifiex_11n_scan_and_dispatch(struct mwifiex_private *priv,
}
}
tbl->start_win = (tbl->start_win + i) & (MAX_TID_VALUE - 1);
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
}

/*
@@ -184,8 +193,6 @@ mwifiex_11n_scan_and_dispatch(struct mwifiex_private *priv,
*
* The function stops the associated timer and dispatches all the
* pending packets in the Rx reorder table before deletion.
- *
- * The caller must hold rx_reorder_tbl_lock spinlock.
*/
static void
mwifiex_del_rx_reorder_entry(struct mwifiex_private *priv,
@@ -211,7 +218,11 @@ mwifiex_del_rx_reorder_entry(struct mwifiex_private *priv,

del_timer_sync(&tbl->timer_context.timer);
tbl->timer_context.timer_is_set = false;
+
+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
list_del(&tbl->list);
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
+
kfree(tbl->rx_reorder_ptr);
kfree(tbl);

@@ -224,17 +235,22 @@ mwifiex_del_rx_reorder_entry(struct mwifiex_private *priv,
/*
* This function returns the pointer to an entry in Rx reordering
* table which matches the given TA/TID pair.
- *
- * The caller must hold rx_reorder_tbl_lock spinlock.
*/
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;

- list_for_each_entry(tbl, &priv->rx_reorder_tbl_ptr, list)
- if (!memcmp(tbl->ta, ta, ETH_ALEN) && tbl->tid == tid)
+ 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;
}
@@ -251,9 +267,14 @@ void mwifiex_11n_del_rx_reorder_tbl_by_ta(struct mwifiex_private *priv, u8 *ta)
return;

spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
- list_for_each_entry_safe(tbl, tmp, &priv->rx_reorder_tbl_ptr, list)
- if (!memcmp(tbl->ta, ta, ETH_ALEN))
+ list_for_each_entry_safe(tbl, tmp, &priv->rx_reorder_tbl_ptr, list) {
+ if (!memcmp(tbl->ta, ta, ETH_ALEN)) {
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock,
+ flags);
mwifiex_del_rx_reorder_entry(priv, tbl);
+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
+ }
+ }
spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);

return;
@@ -262,18 +283,24 @@ void mwifiex_11n_del_rx_reorder_tbl_by_ta(struct mwifiex_private *priv, u8 *ta)
/*
* This function finds the last sequence number used in the packets
* buffered in Rx reordering table.
- *
- * The caller must hold rx_reorder_tbl_lock spinlock.
*/
static int
mwifiex_11n_find_last_seq_num(struct reorder_tmr_cnxt *ctx)
{
struct mwifiex_rx_reorder_tbl *rx_reorder_tbl_ptr = ctx->ptr;
+ struct mwifiex_private *priv = ctx->priv;
+ unsigned long flags;
int i;

- for (i = rx_reorder_tbl_ptr->win_size - 1; i >= 0; --i)
- if (rx_reorder_tbl_ptr->rx_reorder_ptr[i])
+ spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
+ for (i = rx_reorder_tbl_ptr->win_size - 1; i >= 0; --i) {
+ if (rx_reorder_tbl_ptr->rx_reorder_ptr[i]) {
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock,
+ flags);
return i;
+ }
+ }
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);

return -1;
}
@@ -291,22 +318,17 @@ mwifiex_flush_data(struct timer_list *t)
struct reorder_tmr_cnxt *ctx =
from_timer(ctx, t, timer);
int start_win, seq_num;
- unsigned long flags;

ctx->timer_is_set = false;
- spin_lock_irqsave(&ctx->priv->rx_reorder_tbl_lock, flags);
seq_num = mwifiex_11n_find_last_seq_num(ctx);

- if (seq_num < 0) {
- spin_unlock_irqrestore(&ctx->priv->rx_reorder_tbl_lock, flags);
+ if (seq_num < 0)
return;
- }

mwifiex_dbg(ctx->priv->adapter, INFO, "info: flush data %d\n", seq_num);
start_win = (ctx->ptr->start_win + seq_num + 1) & (MAX_TID_VALUE - 1);
mwifiex_11n_dispatch_pkt_until_start_win(ctx->priv, ctx->ptr,
start_win);
- spin_unlock_irqrestore(&ctx->priv->rx_reorder_tbl_lock, flags);
}

/*
@@ -333,14 +355,11 @@ mwifiex_11n_create_rx_reorder_tbl(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)
@@ -551,20 +570,16 @@ int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private *priv,
int prev_start_win, start_win, end_win, win_size;
u16 pkt_index;
bool init_window_shift = false;
- unsigned long flags;
int ret = 0;

- 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;
}
@@ -651,8 +666,6 @@ 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;
}

@@ -681,18 +694,14 @@ mwifiex_del_ba_tbl(struct mwifiex_private *priv, int tid, u8 *peer_mac,
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) {
@@ -726,7 +735,6 @@ 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);

@@ -740,20 +748,17 @@ 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) {
@@ -764,7 +769,6 @@ 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",
@@ -804,8 +808,11 @@ void mwifiex_11n_cleanup_reorder_tbl(struct mwifiex_private *priv)

spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
list_for_each_entry_safe(del_tbl_ptr, tmp_node,
- &priv->rx_reorder_tbl_ptr, list)
+ &priv->rx_reorder_tbl_ptr, list) {
+ spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
mwifiex_del_rx_reorder_entry(priv, del_tbl_ptr);
+ 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);

@@ -929,7 +936,6 @@ 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);
@@ -949,18 +955,14 @@ 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 a83c5afc256a..5ce85d5727e4 100644
--- a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
+++ b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
@@ -421,15 +421,12 @@ 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))) {
ret = mwifiex_handle_uap_rx_forward(priv, skb);
- spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
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);
--
2.20.0.rc1.387.gf8505762e3-goog