Return-path: Received: from omr2.cc.vt.edu ([198.82.141.100]:35719 "EHLO omr2.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751633AbaHSRwm (ORCPT ); Tue, 19 Aug 2014 13:52:42 -0400 To: Hugh Dickins Cc: Vincent Donnefort , Bryan Wu , linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org Subject: Re: 3.17-rc1: leds blink workqueue causes sleeping BUGs In-Reply-To: Your message of "Sat, 16 Aug 2014 20:27:01 -0700." From: Valdis.Kletnieks@vt.edu References: Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1408467967_2094P"; micalg=pgp-sha1; protocol="application/pgp-signature" Date: Tue, 19 Aug 2014 13:06:07 -0400 Message-ID: <10857.1408467967@turing-police.cc.vt.edu> (sfid-20140819_195250_367586_7F754865) Sender: linux-wireless-owner@vger.kernel.org List-ID: --==_Exmh_1408467967_2094P Content-Type: text/plain; charset=us-ascii On Sat, 16 Aug 2014 20:27:01 -0700, Hugh Dickins said: > Can we safely revert your 8b37e1bef5a6 ("leds: convert blink timer to > workqueue"), or have there been other changes which now depend upon it? I suspect there's something else busted. I hand-reverted that patch, and I *still* see the following lockdep whine that looks related (as it talks about leddev_list_lock). next-0811 was OK, looks like next-0815 and -0818 had this.... [ 2.473044] iTCO_vendor_support: vendor-support=0 [ 2.473122] device-mapper: uevent: version 1.0.3 [ 2.473145] ============================================= [ 2.473177] [ INFO: possible recursive locking detected ] [ 2.473204] 3.17.0-rc1-next-20140818-dirty #274 Not tainted [ 2.473231] --------------------------------------------- [ 2.473258] kworker/3:0/25 is trying to acquire lock: [ 2.473283] (&trig->leddev_list_lock){.+.?..}, at: [] led_trigger_event+0x26/0x69 [ 2.473341] but task is already holding lock: [ 2.473370] (&trig->leddev_list_lock){.+.?..}, at: [] led_trigger_event+0x26/0x69 [ 2.473425] other info that might help us debug this: [ 2.473456] Possible unsafe locking scenario: [ 2.473485] CPU0 [ 2.473498] ---- [ 2.473511] lock(&trig->leddev_list_lock); [ 2.473538] lock(&trig->leddev_list_lock); [ 2.473565] *** DEADLOCK *** [ 2.473594] May be due to missing lock nesting notation [ 2.473626] 11 locks held by kworker/3:0/25: [ 2.473648] #0: ("events_long"){.+.+.+}, at: [] process_one_work+0x1e9/0x4ad [ 2.473704] #1: (serio_event_work){+.+.+.}, at: [] process_one_work+0x1e9/0x4ad [ 2.473760] #2: (serio_mutex){+.+.+.}, at: [] serio_handle_event+0x19/0x19c [ 2.473816] #3: (&dev->mutex){......}, at: [] __driver_attach+0x2f/0x7e [ 2.473869] #4: (&dev->mutex){......}, at: [] __driver_attach+0x47/0x7e [ 2.473922] #5: (&serio->drv_mutex){+.+.+.}, at: [] serio_connect_driver+0x21/0x42 [ 2.473980] #6: (input_mutex){+.+.+.}, at: [] input_register_device+0x2a9/0x381 [ 2.474036] #7: (vt_led_registered_lock){+.+.+.}, at: [] input_led_connect+0x49/0x1cd [ 2.474095] #8: (triggers_list_lock){++++.+}, at: [] led_trigger_set_default+0x27/0x87 [ 2.474154] #9: (&led_cdev->trigger_lock){+.+.+.}, at: [] led_trigger_set_default+0x2f/0x87 [ 2.474214] #10: (&trig->leddev_list_lock){.+.?..}, at: [] led_trigger_event+0x26/0x69 [ 2.474274] stack backtrace: [ 2.474297] CPU: 3 PID: 25 Comm: kworker/3:0 Not tainted 3.17.0-rc1-next-20140818-dirty #274 [ 2.474338] Hardware name: Dell Inc. Latitude E6530/07Y85M, BIOS A15 06/20/2014 [ 2.474374] Workqueue: events_long serio_handle_event [ 2.474401] 0000000000000000 ffff880224ceb960 ffffffff9368ba02 ffffffff945ff130 [ 2.474447] ffffffff945ff130 ffff880224ceba20 ffffffff9307b730 0000000a00000246 [ 2.474492] 0000000000000000 ffffffff945ff130 ffffffff00000003 23605381dcae248d [ 2.474538] Call Trace: [ 2.474554] [] dump_stack+0x51/0xaa [ 2.474581] [] __lock_acquire+0xd22/0xed1 [ 2.474611] [] ? __lock_acquire+0x68c/0xed1 [ 2.474641] [] ? led_trigger_event+0x26/0x69 [ 2.474671] [] lock_acquire+0xdd/0x16a [ 2.474699] [] ? lock_acquire+0xdd/0x16a [ 2.474727] [] ? led_trigger_event+0x26/0x69 [ 2.474758] [] _raw_read_lock+0x30/0x3f [ 2.474786] [] ? led_trigger_event+0x26/0x69 [ 2.474816] [] led_trigger_event+0x26/0x69 [ 2.474846] [] vt_led_set+0x32/0x34 [ 2.474873] [] __led_set_brightness+0x1b/0x1d [ 2.474904] [] led_set_brightness+0x37/0x39 [ 2.474934] [] led_trigger_event+0x48/0x69 [ 2.474965] [] kbd_ledstate_trigger_activate+0x47/0x4f [ 2.474999] [] led_trigger_set+0xfd/0x139 [ 2.475028] [] led_trigger_set_default+0x62/0x87 [ 2.475061] [] led_classdev_register+0x139/0x144 [ 2.475093] [] input_led_connect+0x8a/0x1cd [ 2.475123] [] input_register_device+0x370/0x381 [ 2.475154] [] atkbd_connect+0x216/0x269 [ 2.475182] [] serio_connect_driver+0x2c/0x42 [ 2.475213] [] serio_driver_probe+0x1b/0x1d [ 2.476508] [] driver_probe_device+0xda/0x203 [ 2.477797] [] __driver_attach+0x5c/0x7e [ 2.479081] [] ? __device_attach+0x38/0x38 [ 2.480328] [] bus_for_each_dev+0x6a/0x82 [ 2.481604] [] driver_attach+0x19/0x1b [ 2.482874] [] serio_handle_event+0x156/0x19c [ 2.483387] ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300) [ 2.485373] [] process_one_work+0x28b/0x4ad [ 2.485976] ata1.00: ACPI cmd ef/10:06:00:00:00:00 (SET FEATURES) succeeded [ 2.485979] ata1.00: ACPI cmd f5/00:00:00:00:00:00 (SECURITY FREEZE LOCK) filtered out [ 2.485982] ata1.00: ACPI cmd b1/c1:00:00:00:00:00 (DEVICE CONFIGURATION OVERLAY) filtered out [ 2.486523] ata1.00: ACPI cmd 00/00:00:00:00:00:a0 (NOP) rejected by device (Stat=0x51 Err=0x04) [ 2.489121] ata1.00: ATA-8: ST500LX003-1AC15G, DEM4, max UDMA/133 [ 2.489123] ata1.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 31/32) [ 2.492676] ata1.00: ACPI cmd ef/10:06:00:00:00:00 (SET FEATURES) succeeded [ 2.492678] ata1.00: ACPI cmd f5/00:00:00:00:00:00 (SECURITY FREEZE LOCK) filtered out [ 2.492681] ata1.00: ACPI cmd b1/c1:00:00:00:00:00 (DEVICE CONFIGURATION OVERLAY) filtered out [ 2.493213] ata1.00: ACPI cmd 00/00:00:00:00:00:a0 (NOP) rejected by device (Stat=0x51 Err=0x04) [ 2.495797] ata1.00: configured for UDMA/133 [ 2.497541] scsi 0:0:0:0: Direct-Access ATA ST500LX003-1AC15 DEM4 PQ: 0 ANSI: 5 [ 2.498023] sd 0:0:0:0: [sda] 976773168 512-byte logical blocks: (500 GB/465 GiB) [ 2.498026] sd 0:0:0:0: [sda] 4096-byte physical blocks [ 2.498169] sd 0:0:0:0: [sda] Write Protect is off [ 2.498172] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [ 2.498231] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 2.505326] sda: sda1 sda2 sda3 [ 2.506172] sd 0:0:0:0: [sda] Attached SCSI disk [ 2.511495] [] worker_thread+0x351/0x46a [ 2.512855] [] ? process_scheduled_works+0x2a/0x2a [ 2.514195] [] kthread+0xd6/0xde [ 2.515521] [] ? __kthread_parkme+0x62/0x62 [ 2.516814] [] ret_from_fork+0x7c/0xb0 [ 2.518095] [] ? __kthread_parkme+0x62/0x62 [ 2.519527] device-mapper: ioctl: 4.27.0-ioctl (2013-10-30) initialised: dm-devel@redhat.com [ 2.520836] Intel P-state driver initializing. (Looks like the lockdep output got intermixed with ata spinning up my disk) --==_Exmh_1408467967_2094P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Exmh version 2.5 07/13/2001 iQIVAwUBU/OD/wdmEQWDXROgAQK5GhAAq3CXeIA8qKtZ0oPOfdKqG2Ciby2CSdjP qGLhTUfDGz80fpaD4IYpMRRiNYaPjHTdJNwNfX9061gZub64v8Qi+KUDnS7w11Pa +61GoPW3rIv3g5Zyk1Z2D6vJAOXeMugCOwPvG/qo6aX5QcD0CeuaiwbocDMf4xOd ZuG30f5lisezQde8YYdNQ+cjjO/RQox8IDmb67rU1oa53Kj81F6Oa4iaxlaVJdUK cFxSARcO+cZQPC4QqTWtZfzKyYwHTgzubRMMz9DQAXkUp7rwAPdMaC+T1DVFq8Z/ s7X+OK8jQ+Z1eyXNn48uZJxDzelIc+0h4Rsbus2XQb3N9KHoanXocR/RexJE/MUZ xViOUkT8DTRe8tHCZMQA2ukO8uTOTaCVTwAdP7jmQSnP8mFd0LGYgIFhOP7p57pE ENTSfK8r8aWxeQzWSLUTnU1r2sY4UGv7EXhceubw409kwcbaSYJ3iLbRFusLI81I Y2JEAxv5DPoF+dvroI4JUjjRnfqEnM/LIVUXckdBtyLqcSekT25tBi2pvaNWbPaF GAipiYjcf4I3g+lvtYrBTguWrmFzScsFbUfS5bq06DiJcR6fy5E0k8fb947k318a R6UPnRHqvXcUsF/AIpJfwCLsaVLN491Yk+hu1g0/OAd/bW72Q+HQUa1E6/FrCFRS jBYotT4KUb4= =7IUy -----END PGP SIGNATURE----- --==_Exmh_1408467967_2094P--