• Ben Greear's avatar
    ath10k: fix deadlock when peer cannot be created · fee48cf8
    Ben Greear authored
    We must not attempt to send WMI packets while holding the data-lock,
    as it may deadlock:
    
    BUG: sleeping function called from invalid context at drivers/net/wireless/ath/ath10k/wmi.c:1824
    in_atomic(): 1, irqs_disabled(): 0, pid: 2878, name: wpa_supplicant
    
    =============================================
    [ INFO: possible recursive locking detected ]
    4.4.6+ #21 Tainted: G        W  O
    ---------------------------------------------
    wpa_supplicant/2878 is trying to acquire lock:
     (&(&ar->data_lock)->rlock){+.-...}, at: [<ffffffffa0721511>] ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core]
    
    but task is already holding lock:
     (&(&ar->data_lock)->rlock){+.-...}, at: [<ffffffffa070251b>] ath10k_peer_create+0x122/0x1ae [ath10k_core]
    
    other info that might help us debug this:
     Possible unsafe locking scenario:
    
           CPU0
           ----
      lock(&(&ar->data_lock)->rlock);
      lock(&(&ar->data_lock)->rlock);
    
     *** DEADLOCK ***
    
     May be due to missing lock nesting notation
    
    4 locks held by wpa_supplicant/2878:
     #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff816493ca>] rtnl_lock+0x12/0x14
     #1:  (&ar->conf_mutex){+.+.+.}, at: [<ffffffffa0706932>] ath10k_add_interface+0x3b/0xbda [ath10k_core]
     #2:  (&(&ar->data_lock)->rlock){+.-...}, at: [<ffffffffa070251b>] ath10k_peer_create+0x122/0x1ae [ath10k_core]
     #3:  (rcu_read_lock){......}, at: [<ffffffffa062f304>] rcu_read_lock+0x0/0x66 [mac80211]
    
    stack backtrace:
    CPU: 3 PID: 2878 Comm: wpa_supplicant Tainted: G        W  O    4.4.6+ #21
    Hardware name: To be filled by O.E.M. To be filled by O.E.M./ChiefRiver, BIOS 4.6.5 06/07/2013
     0000000000000000 ffff8801fcadf8f0 ffffffff8137086d ffffffff82681720
     ffffffff82681720 ffff8801fcadf9b0 ffffffff8112e3be ffff8801fcadf920
     0000000100000000 ffffffff82681720 ffffffffa0721500 ffff8801fcb8d348
    Call Trace:
     [<ffffffff8137086d>] dump_stack+0x81/0xb6
     [<ffffffff8112e3be>] __lock_acquire+0xc5b/0xde7
     [<ffffffffa0721500>] ? ath10k_wmi_tx_beacons_iter+0x15/0x11a [ath10k_core]
     [<ffffffff8112d0d0>] ? mark_lock+0x24/0x201
     [<ffffffff8112e908>] lock_acquire+0x132/0x1cb
     [<ffffffff8112e908>] ? lock_acquire+0x132/0x1cb
     [<ffffffffa0721511>] ? ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core]
     [<ffffffffa07214eb>] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core]
     [<ffffffff816f9e2b>] _raw_spin_lock_bh+0x31/0x40
     [<ffffffffa0721511>] ? ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core]
     [<ffffffffa0721511>] ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core]
     [<ffffffffa07214eb>] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core]
     [<ffffffffa062eb18>] __iterate_interfaces+0x9d/0x13d [mac80211]
     [<ffffffffa062f609>] ieee80211_iterate_active_interfaces_atomic+0x32/0x3e [mac80211]
     [<ffffffffa07214eb>] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core]
     [<ffffffffa071fa9f>] ath10k_wmi_tx_beacons_nowait.isra.13+0x14/0x16 [ath10k_core]
     [<ffffffffa0721676>] ath10k_wmi_cmd_send+0x71/0x242 [ath10k_core]
     [<ffffffffa07023f6>] ath10k_wmi_peer_delete+0x3f/0x42 [ath10k_core]
     [<ffffffffa0702557>] ath10k_peer_create+0x15e/0x1ae [ath10k_core]
     [<ffffffffa0707004>] ath10k_add_interface+0x70d/0xbda [ath10k_core]
     [<ffffffffa05fffcc>] drv_add_interface+0x123/0x1a5 [mac80211]
     [<ffffffffa061554b>] ieee80211_do_open+0x351/0x667 [mac80211]
     [<ffffffffa06158aa>] ieee80211_open+0x49/0x4c [mac80211]
     [<ffffffff8163ecf9>] __dev_open+0x88/0xde
     [<ffffffff8163ef6e>] __dev_change_flags+0xa4/0x13a
     [<ffffffff8163f023>] dev_change_flags+0x1f/0x54
     [<ffffffff816a5532>] devinet_ioctl+0x2b9/0x5c9
     [<ffffffff816514dd>] ? copy_to_user+0x32/0x38
     [<ffffffff816a6115>] inet_ioctl+0x81/0x9d
     [<ffffffff816a6115>] ? inet_ioctl+0x81/0x9d
     [<ffffffff81621cf8>] sock_do_ioctl+0x20/0x3d
     [<ffffffff816223c4>] sock_ioctl+0x222/0x22e
     [<ffffffff8121cf95>] do_vfs_ioctl+0x453/0x4d7
     [<ffffffff81625603>] ? __sys_recvmsg+0x4c/0x5b
     [<ffffffff81225af1>] ? __fget_light+0x48/0x6c
     [<ffffffff8121d06b>] SyS_ioctl+0x52/0x74
     [<ffffffff816fa736>] entry_SYSCALL_64_fastpath+0x16/0x7a
    Signed-off-by: default avatarBen Greear <greearb@candelatech.com>
    Signed-off-by: default avatarKalle Valo <kvalo@qca.qualcomm.com>
    fee48cf8
mac.c 198 KB