From patchwork Fri Apr 1 21:12:12 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Greear X-Patchwork-Id: 8727841 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: X-Original-To: patchwork-ath10k@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0C679C0554 for ; Fri, 1 Apr 2016 21:13:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1C0FA203A4 for ; Fri, 1 Apr 2016 21:13:21 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 22E4120148 for ; Fri, 1 Apr 2016 21:13:20 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1am6NN-0001i9-QR; Fri, 01 Apr 2016 21:13:05 +0000 Received: from merlin.infradead.org ([2001:4978:20e::2]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1am6NL-0001hR-Az for ath10k@bombadil.infradead.org; Fri, 01 Apr 2016 21:13:03 +0000 Received: from mail2.candelatech.com ([208.74.158.173]) by merlin.infradead.org with esmtp (Exim 4.85 #2 (Red Hat Linux)) id 1am6NJ-0000lk-VY for ath10k@lists.infradead.org; Fri, 01 Apr 2016 21:13:02 +0000 Received: from ben-dt3.candelatech.com (firewall.candelatech.com [50.251.239.81]) by mail2.candelatech.com (Postfix) with ESMTP id 82ED040ECA9; Fri, 1 Apr 2016 14:12:20 -0700 (PDT) From: greearb@candelatech.com To: ath10k@lists.infradead.org Subject: [PATCH v2 5/5] ath10k: Fix deadlock when peer cannot be created. Date: Fri, 1 Apr 2016 14:12:12 -0700 Message-Id: <1459545132-11295-5-git-send-email-greearb@candelatech.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1459545132-11295-1-git-send-email-greearb@candelatech.com> References: <1459545132-11295-1-git-send-email-greearb@candelatech.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160401_171302_219698_37D88862 X-CRM114-Status: UNSURE ( 8.51 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.9 (--) X-BeenThere: ath10k@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ben Greear , linux-wireless@vger.kernel.org MIME-Version: 1.0 Sender: "ath10k" Errors-To: ath10k-bounces+patchwork-ath10k=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Ben Greear 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: [] ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core] but task is already holding lock: (&(&ar->data_lock)->rlock){+.-...}, at: [] 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: [] rtnl_lock+0x12/0x14 #1: (&ar->conf_mutex){+.+.+.}, at: [] ath10k_add_interface+0x3b/0xbda [ath10k_core] #2: (&(&ar->data_lock)->rlock){+.-...}, at: [] ath10k_peer_create+0x122/0x1ae [ath10k_core] #3: (rcu_read_lock){......}, at: [] 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: [] dump_stack+0x81/0xb6 [] __lock_acquire+0xc5b/0xde7 [] ? ath10k_wmi_tx_beacons_iter+0x15/0x11a [ath10k_core] [] ? mark_lock+0x24/0x201 [] lock_acquire+0x132/0x1cb [] ? lock_acquire+0x132/0x1cb [] ? ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core] [] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core] [] _raw_spin_lock_bh+0x31/0x40 [] ? ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core] [] ath10k_wmi_tx_beacons_iter+0x26/0x11a [ath10k_core] [] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core] [] __iterate_interfaces+0x9d/0x13d [mac80211] [] ieee80211_iterate_active_interfaces_atomic+0x32/0x3e [mac80211] [] ? ath10k_wmi_cmd_send_nowait+0x1ce/0x1ce [ath10k_core] [] ath10k_wmi_tx_beacons_nowait.isra.13+0x14/0x16 [ath10k_core] [] ath10k_wmi_cmd_send+0x71/0x242 [ath10k_core] [] ath10k_wmi_peer_delete+0x3f/0x42 [ath10k_core] [] ath10k_peer_create+0x15e/0x1ae [ath10k_core] [] ath10k_add_interface+0x70d/0xbda [ath10k_core] [] drv_add_interface+0x123/0x1a5 [mac80211] [] ieee80211_do_open+0x351/0x667 [mac80211] [] ieee80211_open+0x49/0x4c [mac80211] [] __dev_open+0x88/0xde [] __dev_change_flags+0xa4/0x13a [] dev_change_flags+0x1f/0x54 [] devinet_ioctl+0x2b9/0x5c9 [] ? copy_to_user+0x32/0x38 [] inet_ioctl+0x81/0x9d [] ? inet_ioctl+0x81/0x9d [] sock_do_ioctl+0x20/0x3d [] sock_ioctl+0x222/0x22e [] do_vfs_ioctl+0x453/0x4d7 [] ? __sys_recvmsg+0x4c/0x5b [] ? __fget_light+0x48/0x6c [] SyS_ioctl+0x52/0x74 [] entry_SYSCALL_64_fastpath+0x16/0x7a Signed-off-by: Ben Greear --- drivers/net/wireless/ath/ath10k/mac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index 020dd25..be8345c 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -700,10 +700,10 @@ static int ath10k_peer_create(struct ath10k *ar, peer = ath10k_peer_find(ar, vdev_id, addr); if (!peer) { + spin_unlock_bh(&ar->data_lock); ath10k_warn(ar, "failed to find peer %pM on vdev %i after creation\n", addr, vdev_id); ath10k_wmi_peer_delete(ar, vdev_id, addr); - spin_unlock_bh(&ar->data_lock); return -ENOENT; }