package/kernel/mac80211/patches/020-02-rt2x00usb-do-not-anchor-rx-and-tx-urb-s.patch

   1 From 93c7018ec16bb83399dd4db61c361a6d6aba0d5a Mon Sep 17 00:00:00 2001
   2 From: Stanislaw Gruszka <sgruszka@redhat.com>
   3 Date: Wed, 8 Feb 2017 12:18:09 +0100
   4 Subject: [PATCH 02/19] rt2x00usb: do not anchor rx and tx urb's
   5
   6 We might kill TX or RX urb during rt2x00usb_flush_entry(), what can
   7 cause anchor list corruption like shown below:
   8
   9 [ 2074.035633] WARNING: CPU: 2 PID: 14480 at lib/list_debug.c:33 __list_add+0xac/0xc0
  10 [ 2074.035634] list_add corruption. prev->next should be next (ffff88020f362c28), but was dead000000000100. (prev=ffff8801d161bb70).
  11 <snip>
  12 [ 2074.035670] Call Trace:
  13 [ 2074.035672]  [<ffffffff813bde47>] dump_stack+0x63/0x8c
  14 [ 2074.035674]  [<ffffffff810a2231>] __warn+0xd1/0xf0
  15 [ 2074.035676]  [<ffffffff810a22af>] warn_slowpath_fmt+0x5f/0x80
  16 [ 2074.035678]  [<ffffffffa073855d>] ? rt2x00usb_register_write_lock+0x3d/0x60 [rt2800usb]
  17 [ 2074.035679]  [<ffffffff813dbe4c>] __list_add+0xac/0xc0
  18 [ 2074.035681]  [<ffffffff81591c6c>] usb_anchor_urb+0x4c/0xa0
  19 [ 2074.035683]  [<ffffffffa07322af>] rt2x00usb_kick_rx_entry+0xaf/0x100 [rt2x00usb]
  20 [ 2074.035684]  [<ffffffffa0732322>] rt2x00usb_clear_entry+0x22/0x30 [rt2x00usb]
  21
  22 To fix do not anchor TX and RX urb's, it is not needed as during
  23 shutdown we kill those urbs in rt2x00usb_free_entries().
  24
  25 Cc: Vishal Thanki <vishalthanki@gmail.com>
  26 Fixes: 8b4c0009313f ("rt2x00usb: Use usb anchor to manage URB")
  27 Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
  28 Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
  29 ---
  30  drivers/net/wireless/ralink/rt2x00/rt2x00usb.c | 4 ----
  31  1 file changed, 4 deletions(-)
  32
  33 --- a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
  34 +++ b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
  35 @@ -319,10 +319,8 @@ static bool rt2x00usb_kick_tx_entry(stru
  36                           entry->skb->data, length,
  37                           rt2x00usb_interrupt_txdone, entry);
  38
  39 -       usb_anchor_urb(entry_priv->urb, rt2x00dev->anchor);
  40         status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
  41         if (status) {
  42 -               usb_unanchor_urb(entry_priv->urb);
  43                 if (status == -ENODEV)
  44                         clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
  45                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
  46 @@ -410,10 +408,8 @@ static bool rt2x00usb_kick_rx_entry(stru
  47                           entry->skb->data, entry->skb->len,
  48                           rt2x00usb_interrupt_rxdone, entry);
  49
  50 -       usb_anchor_urb(entry_priv->urb, rt2x00dev->anchor);
  51         status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
  52         if (status) {
  53 -               usb_unanchor_urb(entry_priv->urb);
  54                 if (status == -ENODEV)
  55                         clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
  56                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);