Return-Path: Date: Wed, 10 Jul 2013 18:30:32 +0100 From: Gustavo Padovan To: Sedat Dilek Cc: Stephen Rothwell , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, Marcel Holtmann , Johan Hedberg , Linux PM List , "Rafael J. Wysocki" Subject: Re: linux-next: Tree for Apr 26 [ bluetooth on suspend/resume ] Message-ID: <20130710173032.GF2952@joana> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: List-ID: Hi Sedat, * Sedat Dilek [2013-04-26 19:40:20 +0200]: > On Fri, Apr 26, 2013 at 7:32 PM, Sedat Dilek wrote: > > On Fri, Apr 26, 2013 at 7:30 PM, Sedat Dilek wrote: > >> On Fri, Apr 26, 2013 at 10:03 AM, Stephen Rothwell wrote: > >>> Hi all, > >>> > >>> Changes since 20130424: > >>> > >>> Removed tree: ppc-temp (remerged into powerpc) > >>> > >>> The net-next tree gained conflicts against the net and pci trees and a > >>> build failure for which I applied a merge fix patch. > >>> > >>> The omap_dss2 tree gained a build failure so I used the version from > >>> next-20130424. > >>> > >>> The trivial tree gained a conflict against the arm tree. > >>> > >>> The staging tree still had its build failure for which I applied a > >>> supplied patch. > >>> > >>> The arm-soc tree gained a conflict against the spi-mb tree. > >>> > >>> The renesas tree gained a conflict against the input tree. > >>> > >> > >> [ CC linux-bluetooth + linux-pm folks ] > >> > >> I see the following: > >> > >> [ 176.667799] PM: Syncing filesystems ... done. > >> [ 176.670014] PM: Preparing system for mem sleep > >> [ 176.670422] Freezing user space processes ... > >> [ 196.656719] Freezing of tasks failed after 20.00 seconds (1 tasks > >> refusing to freeze, wq_busy=0): > >> [ 196.656728] bluetoothd D ffffffff8180d8c0 0 1012 863 0x00000004 > >> [ 196.656731] ffff88008fdb3cc8 0000000000000046 ffff8800926530d0 > >> 0000020000000000 > >> [ 196.656735] ffff88008feca200 ffff88008fdb3fd8 ffff88008fdb3fd8 > >> ffff88008fdb3fd8 > >> [ 196.656738] ffff880119f78300 ffff88008feca200 ffff88008fdb3cf8 > >> ffff880095281950 > >> [ 196.656741] Call Trace: > >> [ 196.656749] [] schedule+0x29/0x70 > >> [ 196.656752] [] schedule_preempt_disabled+0xe/0x10 > >> [ 196.656754] [] __mutex_lock_slowpath+0x125/0x2f0 > >> [ 196.656757] [] mutex_lock+0x1e/0x40 > >> [ 196.656773] [] hci_dev_open+0x51/0x2e0 [bluetooth] > >> [ 196.656780] [] hci_sock_ioctl+0x1f2/0x3f0 [bluetooth] > >> [ 196.656783] [] sock_do_ioctl+0x30/0x70 > >> [ 196.656786] [] sock_ioctl+0x79/0x2f0 > >> [ 196.656790] [] do_vfs_ioctl+0x96/0x560 > >> [ 196.656794] [] SyS_ioctl+0x91/0xb0 > >> [ 196.656797] [] system_call_fastpath+0x1a/0x1f > >> [ 196.656811] > >> [ 196.656812] Restarting tasks ... done. > > > > Forgot to attach dmesg + config, sorry. > > > > Oops, NULL-pointer-deref [ __queue_work() ] > > [ 25.968262] Bluetooth: BNEP socket layer initialized > [ 25.974875] usb 2-1.5: link qh1-0e01/ffff880091bc90c0 start 0 [1/2 us] > [ 25.974932] BUG: unable to handle kernel NULL pointer dereference > at 0000000000000100 > [ 25.974944] IP: [] __queue_work+0x32/0x3d0 > [ 25.974955] PGD 0 > [ 25.974960] Oops: 0000 [#1] SMP > [ 25.974966] Modules linked in: bnep btusb(+) videobuf2_memops > snd_timer drm_kms_helper videobuf2_core snd_seq_device drm parport_pc > bluetooth microcode videodev ppdev psmouse snd cfg80211 soundcore > samsung_laptop wmi lp serio_raw video parport mac_hid lpc_ich > hid_generic usbhid hid r8169 > [ 25.975014] CPU: 3 PID: 1007 Comm: bluetoothd Not tainted > 3.9.0-rc8-next20130426-3-iniza-small #1 > [ 25.975022] Hardware name: SAMSUNG ELECTRONICS CO., LTD. > 530U3BI/530U4BI/530U4BH/530U3BI/530U4BI/530U4BH, BIOS 13XK 03/28/2013 > [ 25.975030] task: ffff88008feda300 ti: ffff88008fed4000 task.ti: > ffff88008fed4000 > [ 25.975037] RIP: 0010:[] [] > __queue_work+0x32/0x3d0 > [ 25.975047] RSP: 0018:ffff88008fed5c48 EFLAGS: 00010046 > [ 25.975052] RAX: 0000000000000096 RBX: 0000000000000292 RCX: 0000000000000000 > [ 25.975058] RDX: ffff880095281850 RSI: 0000000000000000 RDI: 0000000000000100 > [ 25.975063] RBP: ffff88008fed5c88 R08: 0000000000000000 R09: 0000000000000300 > [ 25.975069] R10: ffff880094981a00 R11: 0000000000000000 R12: ffff880095281850 > [ 25.975074] R13: 0000000000000000 R14: 0000000000000100 R15: 00000000000009c4 > [ 25.975081] FS: 00007f2f61707740(0000) GS:ffff88011fac0000(0000) > knlGS:0000000000000000 > [ 25.975088] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 25.975093] CR2: 0000000000000100 CR3: 000000009101f000 CR4: 00000000000407e0 > [ 25.975099] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 25.975104] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > [ 25.975109] Stack: > [ 25.975113] ffff88008fed5c88 ffffffff00000100 ffff880095281000 > 0000000000000292 > [ 25.975124] ffff880095281000 ffff880095281908 ffff88008fed5cf0 > 00000000000009c4 > [ 25.975133] ffff88008fed5ca8 ffffffff81077be5 ffff880095281000 > ffff88008fed5ce8 > [ 25.975143] Call Trace: > [ 25.975151] [] queue_work_on+0x45/0x50 > [ 25.975165] [] hci_req_run+0xbf/0xf0 [bluetooth] > [ 25.975177] [] ? hci_init2_req+0x720/0x720 [bluetooth] > [ 25.975188] [] __hci_req_sync+0xd6/0x1c0 [bluetooth] > [ 25.975197] [] ? try_to_wake_up+0x2b0/0x2b0 > [ 25.975205] [] ? usb_autopm_put_interface+0x30/0x40 > [ 25.975217] [] hci_dev_open+0x275/0x2e0 [bluetooth] > [ 25.975230] [] hci_sock_ioctl+0x1f2/0x3f0 [bluetooth] > [ 25.975238] [] sock_do_ioctl+0x30/0x70 > [ 25.975245] [] sock_ioctl+0x79/0x2f0 > [ 25.975254] [] do_vfs_ioctl+0x96/0x560 > [ 25.975262] [] SyS_ioctl+0x91/0xb0 > [ 25.975271] [] system_call_fastpath+0x1a/0x1f Sorry for the big delay on this one, I lost track of this e-mail. So, the only way I see this happening is a race between hci_register_dev and hci_dev_open. If someone issue a syscall to power the bluetooth device on while hci_register_dev is still running and have not yet created the workqueues. The following patch should help with this, it defers the addition of the device into the list, so hci_dev_open will only see the device if workqueue and other things were already created. Gustavo diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index dc34bfa..ce34960 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -2165,10 +2165,6 @@ int hci_register_dev(struct hci_dev *hdev) BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); - write_lock(&hci_dev_list_lock); - list_add(&hdev->list, &hci_dev_list); - write_unlock(&hci_dev_list_lock); - hdev->workqueue = alloc_workqueue(hdev->name, WQ_HIGHPRI | WQ_UNBOUND | WQ_MEM_RECLAIM, 1); if (!hdev->workqueue) { @@ -2207,6 +2203,10 @@ int hci_register_dev(struct hci_dev *hdev) hci_notify(hdev, HCI_DEV_REG); hci_dev_hold(hdev); + write_lock(&hci_dev_list_lock); + list_add(&hdev->list, &hci_dev_list); + write_unlock(&hci_dev_list_lock); + queue_work(hdev->req_workqueue, &hdev->power_on); return id; @@ -2216,9 +2216,6 @@ err_wqueue: destroy_workqueue(hdev->req_workqueue); err: ida_simple_remove(&hci_index_ida, hdev->id); - write_lock(&hci_dev_list_lock); - list_del(&hdev->list); - write_unlock(&hci_dev_list_lock); return error; }