From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752469AbdIBLKF (ORCPT ); Sat, 2 Sep 2017 07:10:05 -0400 Received: from mout.gmx.net ([212.227.17.20]:59844 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751539AbdIBLKE (ORCPT ); Sat, 2 Sep 2017 07:10:04 -0400 Message-ID: <1504350596.16793.44.camel@gmx.de> Subject: hotplug lockdep splat (tip-rt) From: Mike Galbraith To: LKML Cc: Thomas Gleixner Date: Sat, 02 Sep 2017 13:09:56 +0200 Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:Qi8/bs11sVAXqH6i02SCXjCq7JK97g08x/hGv9Je7yA9/gaUjru DOKL5KGHzpmxng+GksswVZ9CcC0rhXjnInPSLEepDwrgu2E0KcGxc2/4lwFRMFL9ZRKYt1U NCISxPEeMiCU64WKXWiTHUZAXNv9aZ+mGPDfPPk5RwRmI/oZzB6SyBnMR+BgmpKCuvWB/uD GqJsKCOa2cegYn+pOW57w== X-UI-Out-Filterresults: notjunk:1;V01:K0:tKXFP1LXC2Y=:Ihzu7YnYRuzXeEdi9rRI/l PnzsStc92OrQmiNL8vYnArOWyoYcZ/8qcUc6Ua1DoSpCI4qCN+pt8mbLRB2g7mUwCBjpIb/wL qLkaLUImgkF4AN5qXNRBbGKyMeAqp23RTWQc8WM2CgzOnvofI14DPRbiJUwoxwA+jBpM0e6kY Dc/n+LcjM+aF2UJoiF1FFUFVe4elAzFELitmr2A35na6C8+z6GQpraqZdssC4Z/CXz6VQi2hZ jW/KV7c/JYPDBIlIAhOoJIWm03WEKrrTcgozrbUZhC6XEnfLmTlkDTcXU6kZhvXbwlEQ28FMi uBe5ZCL8eCYpKk7cIH8UWEgYA9QBefPT6+jOf6Re8wK10cmy2uS4hyHPWWbuHjTa1MHXlcRRa +QK/KcbB5JLVhggW3fYmj3fzrTiFnXdoDM9WTfm1UUOysEb0q30MOeUrFx8XhcAejjOu9fglW 5lNawOGqhUHrzlyR8Hx1nOnSEEqDcmfqcQybXpiNG9CUlLr1cqIZXKTNXaP9Z75JidZh6Iw5y oarx/sWeicAHulEhgPA8GiGau6dB7/NWihMLh6yeiF6kYNitUu6kQku/ZFqDkz4VcczaKyYCR DAzOW602phZpXyYm+r0w3sHib+HgSHX1vUK7BXJqwDvD64jY+Teei0anKVuBpIh9lG9kGwXOe qgnpxDjiXadsmKPfrf1uJLyspPky6l6Z0mV1VCWE15PlVOD+EBSA9OSckCZY+E7/MakkX7qb/ Xg6eAnEdkD6M33gQeG0CQzRgFBvXTbY90j341y0YaHGOmk7uQhikCBdMjfRJiJ4frbsccR+AJ SfPGuR7nEaaAUld7l0RmaUpYD44bd8QSUPThAo5cq8T9JmlLBY= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.11-rt rolled forward, sprinkle liberally with seasoning of choice. [ 7514.772861] ====================================================== [ 7514.772862] WARNING: possible circular locking dependency detected [ 7514.772863] 4.13.0.g06260ca-rt11-tip-lockdep #20 Tainted: G E [ 7514.772863] ------------------------------------------------------ [ 7514.772867] stress-cpu-hotp/4102 is trying to acquire lock: [ 7514.772867] ((complete)&st->done){+.+.}, at: [] takedown_cpu+0x9a/0x120 [ 7514.772877] [ 7514.772877] but task is already holding lock: [ 7514.772877] (sparse_irq_lock){+.+.}, at: [] takedown_cpu+0x4a/0x120 [ 7514.772879] [ 7514.772879] which lock already depends on the new lock. [ 7514.772879] [ 7514.772879] [ 7514.772879] the existing dependency chain (in reverse order) is: [ 7514.772880] [ 7514.772880] -> #2 (sparse_irq_lock){+.+.}: [ 7514.772889] lock_acquire+0xbd/0x250 [ 7514.772908] _mutex_lock+0x31/0x50 [ 7514.772913] irq_affinity_online_cpu+0x13/0xc0 [ 7514.772914] cpuhp_invoke_callback+0x24c/0x9c0 [ 7514.772914] cpuhp_up_callbacks+0x30/0xb0 [ 7514.772915] cpuhp_thread_fun+0x159/0x170 [ 7514.772918] smpboot_thread_fn+0x268/0x310 [ 7514.772919] kthread+0x145/0x180 [ 7514.772921] ret_from_fork+0x2a/0x40 [ 7514.772922] [ 7514.772922] -> #1 (cpuhp_state){+.+.}: [ 7514.772926] smpboot_thread_fn+0x268/0x310 [ 7514.772927] kthread+0x145/0x180 [ 7514.772928] ret_from_fork+0x2a/0x40 [ 7514.772930] 0xffffffffffffffff [ 7514.772930] [ 7514.772930] -> #0 ((complete)&st->done){+.+.}: [ 7514.772932] __lock_acquire+0x113b/0x1190 [ 7514.772933] lock_acquire+0xbd/0x250 [ 7514.772934] wait_for_completion+0x51/0x120 [ 7514.772935] takedown_cpu+0x9a/0x120 [ 7514.772936] cpuhp_invoke_callback+0x24c/0x9c0 [ 7514.772937] cpuhp_down_callbacks+0x3b/0x80 [ 7514.772939] _cpu_down+0xba/0xf0 [ 7514.772940] do_cpu_down+0x35/0x50 [ 7514.772949] device_offline+0x7d/0xa0 [ 7514.772950] online_store+0x3a/0x70 [ 7514.772959] kernfs_fop_write+0x10a/0x190 [ 7514.772962] __vfs_write+0x23/0x150 [ 7514.772963] vfs_write+0xc2/0x1c0 [ 7514.772964] SyS_write+0x45/0xa0 [ 7514.772965] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 7514.772966] [ 7514.772966] other info that might help us debug this: [ 7514.772966] [ 7514.772966] Chain exists of: [ 7514.772966] (complete)&st->done --> cpuhp_state --> sparse_irq_lock [ 7514.772966] [ 7514.772968] Possible unsafe locking scenario: [ 7514.772968] [ 7514.772968] CPU0 CPU1 [ 7514.772968] ---- ---- [ 7514.772968] lock(sparse_irq_lock); [ 7514.772969] lock(cpuhp_state); [ 7514.772970] lock(sparse_irq_lock); [ 7514.772970] lock((complete)&st->done); [ 7514.772971] [ 7514.772971] *** DEADLOCK *** [ 7514.772971] [ 7514.772972] 8 locks held by stress-cpu-hotp/4102: [ 7514.772972] #0: (sb_writers#4){.+.+}, at: [] vfs_write+0x190/0x1c0 [ 7514.772974] #1: (&of->mutex){+.+.}, at: [] kernfs_fop_write+0xda/0x190 [ 7514.772976] #2: (s_active#140){.+.+}, at: [] kernfs_fop_write+0xe2/0x190 [ 7514.772979] #3: (device_hotplug_lock){+.+.}, at: [] lock_device_hotplug_sysfs+0x11/0x40 [ 7514.772981] #4: (&dev->mutex){....}, at: [] device_offline+0x3f/0xa0 [ 7514.772983] #5: (cpu_add_remove_lock){+.+.}, at: [] do_cpu_down+0x1f/0x50 [ 7514.772985] #6: (cpu_hotplug_lock.rw_sem){++++}, at: [] percpu_down_write+0x21/0x110 [ 7514.772987] #7: (sparse_irq_lock){+.+.}, at: [] takedown_cpu+0x4a/0x120 [ 7514.772989] [ 7514.772989] stack backtrace: [ 7514.772990] CPU: 5 PID: 4102 Comm: stress-cpu-hotp Tainted: G E 4.13.0.g06260ca-rt11-tip-lockdep #20 [ 7514.772991] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 [ 7514.772992] Call Trace: [ 7514.772995] dump_stack+0x7c/0xbf [ 7514.772997] print_circular_bug+0x2d3/0x2e0 [ 7514.772999] ? copy_trace+0xb0/0xb0 [ 7514.773001] check_prev_add+0x666/0x700 [ 7514.773002] ? copy_trace+0xb0/0xb0 [ 7514.773008] ? __stop_cpus+0x51/0x70 [ 7514.773010] ? copy_trace+0xb0/0xb0 [ 7514.773011] __lock_acquire+0x113b/0x1190 [ 7514.773013] ? trace_hardirqs_on_caller+0xf2/0x1a0 [ 7514.773015] lock_acquire+0xbd/0x250 [ 7514.773018] ? takedown_cpu+0x9a/0x120 [ 7514.773020] wait_for_completion+0x51/0x120 [ 7514.773021] ? takedown_cpu+0x9a/0x120 [ 7514.773022] ? cpuhp_invoke_callback+0x9c0/0x9c0 [ 7514.773023] takedown_cpu+0x9a/0x120 [ 7514.773025] ? cpuhp_complete_idle_dead+0x10/0x10 [ 7514.773026] cpuhp_invoke_callback+0x24c/0x9c0 [ 7514.773028] cpuhp_down_callbacks+0x3b/0x80 [ 7514.773030] _cpu_down+0xba/0xf0 [ 7514.773031] do_cpu_down+0x35/0x50 [ 7514.773033] device_offline+0x7d/0xa0 [ 7514.773034] online_store+0x3a/0x70 [ 7514.773036] kernfs_fop_write+0x10a/0x190 [ 7514.773037] __vfs_write+0x23/0x150 [ 7514.773039] ? rcu_read_lock_sched_held+0x9b/0xb0 [ 7514.773043] ? rcu_sync_lockdep_assert+0x2d/0x60 [ 7514.773045] ? __sb_start_write+0x190/0x240 [ 7514.773046] ? vfs_write+0x190/0x1c0 [ 7514.773048] vfs_write+0xc2/0x1c0 [ 7514.773050] SyS_write+0x45/0xa0 [ 7514.773051] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 7514.773053] RIP: 0033:0x7fc5e51fd2d0 [ 7514.773053] RSP: 002b:00007ffd73d17678 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 7514.773054] RAX: ffffffffffffffda RBX: 00007fc5e54bd678 RCX: 00007fc5e51fd2d0 [ 7514.773055] RDX: 0000000000000002 RSI: 00007fc5e5d64000 RDI: 0000000000000001 [ 7514.773056] RBP: 00007fc5e54bd620 R08: 000000000000000a R09: 00007fc5e5d16700 [ 7514.773056] R10: 000000000198bc50 R11: 0000000000000246 R12: 0000000000000110 [ 7514.773057] R13: 00000000000000e4 R14: 0000000000002710 R15: 00000000000000f1