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From: Qian Cai <cai@lca.pw>
To: Waiman Long <longman@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Stephen Rothwell <sfr@canb.auug.org.au>
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	rcu@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Will Deacon <will@kernel.org>, Ingo Molnar <mingo@kernel.org>,
	Frederic Weisbecker <fweisbec@gmail.com>
Subject: Re: Hard lockups due to "tick/common: Make tick_periodic() check for missing ticks"
Date: Thu, 19 Mar 2020 09:58:31 -0400	[thread overview]
Message-ID: <11BEA1A5-2E93-4E01-A05C-A6BA73A74CEB@lca.pw> (raw)
In-Reply-To: <F95F95DE-77D9-4A1D-AA5C-CAC165F6B4C8@lca.pw>



> On Mar 6, 2020, at 10:33 PM, Qian Cai <cai@lca.pw> wrote:
> 
> 
> 
>> On Mar 5, 2020, at 11:06 PM, Qian Cai <cai@lca.pw> wrote:
>> 
> 
> Using this config,
> 
>> https://raw.githubusercontent.com/cailca/linux-mm/master/x86.config
> 
> Reverted the linux-next commit d441dceb5dce (“tick/common: Make tick_periodic() check for missing ticks”)
> fixed the lockup that could easily happen during boot.


Thomas or Stephen, can you back out this patch from linux-next while Waiman is getting to the bottom of it?
I can still reproduce it as today.

[    0.021353][    T1] ... fixed-purpose events:   0
[    0.021353][    T1] ... event mask:             000000000000003f
[    0.021353][    T1] rcu: Hierarchical SRCU implementation.
[    0.021353][    T5] NMI watchdog: Enabled. Permanently consumes one hw-PMU counter.
[    0.021353][    T1] smp: Bringing up secondary CPUs ...
[    0.021353][    T1] x86: Booting SMP configuration:
[    0.021353][    T1] .... node  #0, CPUs:        #1
[    0.021353][    T1] .... node  #1, CPUs:    #2
[    0.021353][    T1]   #3
[    0.021353][    T1] .... node  #2, CPUs:    #4
[    0.021353][    T1]   #5
[    0.021353][    T1] .... node  #3, CPUs:    #6
[    0.021353][    T1]   #7
[    0.021353][    T1] .... node  #4, CPUs:    #8
[    0.000000][    T0] smpboot: CPU 8 Converting physical 0 to logical die 1
[    0.021353][    C0] NMI watchdog: Watchdog detected hard LOCKUP on cpu 0
[    0.021353][    C0] Modules linked in:
[    0.021353][    C0] irq event stamp: 51754775
[    0.021353][    C0] hardirqs last  enabled at (51754775): [<ffffffff936a8117>] _raw_spin_unlock_irq+0x27/0x40
[    0.021353][    C0] hardirqs last disabled at (51754774): [<ffffffff9369c394>] __schedule+0x214/0x1070
[    0.021353][    C0] softirqs last  enabled at (78480): [<ffffffff93a00447>] __do_softirq+0x447/0x766
[    0.021353][    C0] softirqs last disabled at (78463): [<ffffffff92cd2226>] irq_exit+0xd6/0xf0
[    0.021353][    C0] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc6-next-20200319 #1
[    0.021353][    C0] Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 03/09/2018
[    0.021353][    C0] RIP: 0010:lock_is_held_type+0x3e/0x150
[    0.021353][    C0] Code: 02 00 48 83 ec 18 48 89 7d d0 48 8d bb 74 08 00 00 89 75 c4 e8 23 fe 28 00 8b 8b 74 08 00 00 85 c9 0f 85 02 01 00 00 9c 41 5e <fa> 48 c7 c7 b4 8c 93 94 e8 05 fe 28 00 8b 15 23 b8 ba 01 85 d2 74
[    0.021353][    C0] RSP: 0018:ffffc90003177a88 EFLAGS: 00000246
[    0.021353][    C0] RAX: 0000000000000000 RBX: ffff888480e0c040 RCX: 0000000000000000
[    0.021353][    C0] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff888480e0c8b4
[    0.021353][    C0] RBP: ffffc90003177ac8 R08: ffffed110f700fb9 R09: 0000000000000001
[    0.021353][    C0] R10: ffff88887b807dc7 R11: ffffed110f700fb8 R12: ffff888480e0c040
[    0.021353][    C0] R13: 0000000000000000 R14: 0000000000000246 R15: ffff888453444340
[    0.021353][    C0] FS:  0000000000000000(0000) GS:ffff888453400000(0000) knlGS:0000000000000000
[    0.021353][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.021353][    C0] CR2: ffff88887b9ff000 CR3: 00000003a7e12000 CR4: 00000000003406f0
[    0.021353][    C0] Call Trace:
[    0.021353][    C0]  __schedule+0x821/0x1070
[    0.021353][    C0]  ? firmware_map_remove+0xe9/0xe9
[    0.021353][    C0]  schedule+0x95/0x160
[    0.021353][    C0]  do_boot_cpu+0x58c/0xaf0
[    0.021353][    C0]  native_cpu_up+0x298/0x430
[    0.021353][    C0]  ? common_cpu_up+0x150/0x150
[    0.021353][    C0]  bringup_cpu+0x44/0x310
[    0.021353][    C0]  ? timers_prepare_cpu+0x114/0x190
[    0.021353][    C0]  ? takedown_cpu+0x2e0/0x2e0
[    0.021353][    C0]  cpuhp_invoke_callback+0x197/0x1120
[    0.021353][    C0]  ? ring_buffer_record_is_set_on+0x40/0x40
[    0.021353][    C0]  _cpu_up+0x171/0x280
[    0.021353][    C0]  do_cpu_up+0xb1/0x120
[    0.021353][    C0]  cpu_up+0x13/0x20
[    0.021353][    C0]  smp_init+0x91/0x118
[    0.021353][    C0]  kernel_init_freeable+0x221/0x4f8
[    0.021353][    C0]  ? mark_held_locks+0x34/0xb0
[    0.021353][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
[    0.021353][    C0]  ? start_kernel+0x8c0/0x8c0
[    0.021353][    C0]  ? lockdep_hardirqs_on+0x1b0/0x2a0
[    0.021353][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
[    0.021353][    C0]  ? rest_init+0x307/0x307
[    0.021353][    C0]  kernel_init+0x11/0x139
[    0.021353][    C0]  ? rest_init+0x307/0x307
[    0.021353][    C0]  ret_from_fork+0x27/0x50

> 
>> 
>> [    0.013514][    C0] NMI watchdog: Watchdog detected hard LOCKUP on cpu 0 
>> [    0.013514][    C0] Modules linked in: 
>> [    0.013514][    C0] irq event stamp: 64186318 
>> [    0.013514][    C0] hardirqs last  enabled at (64186317): [<ffffffff84c9b107>] _raw_spin_unlock_irq+0x27/0x40 
>> [    0.013514][    C0] hardirqs last disabled at (64186318): [<ffffffff84c8f384>] __schedule+0x214/0x1070 
>> [    0.013514][    C0] softirqs last  enabled at (267904): [<ffffffff85000447>] __do_softirq+0x447/0x766 
>> [    0.013514][    C0] softirqs last disabled at (267897): [<ffffffff842d1f16>] irq_exit+0xd6/0xf0 
>> [    0.013514][    C0] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200305+ #6 
>> [    0.013514][    C0] Hardware name: HP ProLiant BL660c Gen9, BIOS I38 10/17/2018 
>> [    0.013514][    C0] RIP: 0010:lock_is_held_type+0x12a/0x150 
>> [    0.013514][    C0] Code: 41 0f 94 c4 65 48 8b 1c 25 40 0f 02 00 48 8d bb 74 08 00 00 e8 77 c0 28 00 c7 83 74 08 00 00 00 00 00 00 41 56 9d 48 83 c4 18 <44> 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 45 31 e4 eb c7 41 bc 01 
>> [    0.013514][    C0] RSP: 0000:ffffc9000628f9f8 EFLAGS: 00000082 
>> [    0.013514][    C0] RAX: 0000000000000000 RBX: ffff889880efc040 RCX: ffffffff8438b449 
>> [    0.013514][    C0] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff889880efc8b4 
>> [    0.013514][    C0] RBP: ffffc9000628fa20 R08: ffffed1108588a24 R09: ffffed1108588a24 
>> [    0.013514][    C0] R10: ffff888842c4511b R11: 0000000000000000 R12: 0000000000000000 
>> [    0.013514][    C0] R13: ffff889880efc908 R14: 0000000000000046 R15: 0000000000000003 
>> [    0.013514][    C0] FS:  0000000000000000(0000) GS:ffff888842c00000(0000) knlGS:0000000000000000 
>> [    0.013514][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 
>> [    0.013514][    C0] CR2: ffff88a0707ff000 CR3: 0000000b72012001 CR4: 00000000001606f0 
>> [    0.013514][    C0] Call Trace: 
>> [    0.013514][    C0]  rcu_read_lock_sched_held+0xac/0xe0 
>> lock_is_held at include/linux/lockdep.h:361
>> (inlined by) rcu_read_lock_sched_held at kernel/rcu/update.c:121
>> [    0.013514][    C0]  ? rcu_read_lock_bh_held+0xc0/0xc0 
>> [    0.013514][    C0]  rcu_note_context_switcx186/0x3b0 
>> [    0.013514][    C0]  __schedule+0x21f/0x1070 
>> [    0.013514][    C0]  ? __sched_text_start+0x8/0x8 
>> [    0.013514][    C0]  schedule+0x95/0x160 
>> [    0.013514][    C0]  do_boot_cpu+0x58c/0xaf0 
>> [    0.013514][    C0]  native_cpu_up+0x298/0x430 
>> [    0.013514][    C0]  ? common_cpu_up+0x150/0x150 
>> [    0.013514][    C0]  bringup_cpu+0x44/0x310 
>> [    0.013514][    C0]  ? timers_prepare_cpu+0x114/0x190 
>> [    0.013514][    C0]  ? takedown_cpu+0x2e0/0x2e0 
>> [    0.013514][    C0]  cpuhp_invoke_callback+0x197/0x1120 
>> [    0.013514][    C0]  ? ring_buffer_record_is_set_on+0x40/0x40 
>> [    0.013514][    C0]  _cpu_up+0x171/0x280 
>> [    0.013514][    C0]  do_cpu_up+0xb1/0x120 
>> [    0.013514][    C0]  cpu_up+0x13/0x20 
>> [    0.013514][    C0]  smp_init+0x91/0x118 
>> [    0.013514][    C0]  kernel_init_freeable+0x221/0x4f8 
>> [    0.013514][    C0]  ? mark_held_locks+0x34/0xb0 
>> [    0.013514][    C0]  ? _raw_spin_unlock_irq+0x27/0x40 
>> [    0.013514][    C0]  ? start_kernel+0x876/0x876 
>> [    0.013514][    C0]  ? lockdep_hardirqs_on+0x1b0/0x2a0 
>> [    0.013514][    C0]  ? _raw_spin_unlock_irq+0x27/0x40 
>> [    0.013514][    C0]  ? rest_init+0x307/0x307 
>> [    0.013514][    C0]  kernel_init+0x  0.013514][    C0]  ? rest_init+0x307/0x307 
>> [    0.013514][    C0]  ret_from_fork+0x3a/0x50 
>> 
> 
> We could have many slightly different traces,
> 
> [    0.000000][    T0] smpboot: CPU 8 Converting physical 0 to logical die 1
> [    0.021496][    C0] NMI watchdog: Watchdog detected hard LOCKUP on cpu 0
> [    0.021496][    C0] Modules linked in:
> [    0.021496][    C0] irq event stamp: 53241496
> [    0.021496][    C0] hardirqs last  enabled at (53241495): [<ffffffffa9c8c037>] _raw_spin_unlock_irq+0x27/0x40
> [    0.021496][    C0] hardirqs last disabled at (53241496): [<ffffffffa9c80244>] __schedule+0x214/0x1070
> [    0.021496][    C0] softirqs last  enabled at (88160): [<ffffffffaa000447>] __do_softirq+0x447/0x766
> [    0.021496][    C0] softirqs last disabled at (88153): [<ffffffffa92d0c66>] irq_exit+0xd6/0xf0
> [    0.021496][    C0] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4+ #25
> [    0.021496][    C0] Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 03/09/2018
> [    0.021496][    C0] RIP: 0010:__asan_load8+0x0/0xa0
> [    0.021496][    C0] Code: e8 03 0f b6 04 30 84 c0 74 c2 38 d0 0f 9e c0 84 c0 74 b9 ba 01 00 00 00 be 04 00 00 00 e8 c8 e3 ff ff 5d c3 66 0f 1f 44 00 00 <55> 48 89 e5 48 8b 4d 08 eb 3a 0f 1f 00 48 b8 00 00 00 00 00 00 00
> [    0.021496][    C0] RSP: 0018:ffffc900031779d8 EFLAGS: 00000082
> [    0.021496][    C0] RAX: 000000000000000f RBX: ffff88820f118040 RCX: ffffffffa9386e1c
> [    0.021496][    C0] RDX: ffff88820f1188b0 RSI: ffff8884534442d8 RDI: ffff88820f118938
> [    0.021496][    C0] RBP: ffffc90003177a10 R08: ffffed1041e23009 R09: ffffed1041e23009
> [    0.021496][    C0] R10: ffffed1041e23008 R11: 0000000000000000 R12: ffff88820f118928
> [    0.021496][    C0] R13: ffff8884534442d8 R14: 0000000000000003 R15: ffff88820f118928
> [    0.021496][    C0] FS:  0000000000000000(0000) GS:ffff888453400000(0000) knlGS:0000000000000000
> [    0.021496][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    0.021496][    C0] CR2: ffff88887b9ff000 CR3: 0000000257c12000 CR4: 00000000003406f0
> [    0.021496][    C0] Call Trace:
> [    0.021496][    C0]  ? match_held_lock+0x20/0x250
> [    0.021496][    C0]  lock_unpin_lock+0x16a/0x260
> [    0.021496][    C0]  ? lock_repin_lock+0x210/0x210
> [    0.021496][    C0]  ? __kasan_check_read+0x11/0x20
> [    0.021496][    C0]  ? pick_next_task_fair+0x3a6/0x6b0
> [    0.021496][    C0]  __schedule+0xd4f/0x1070
> [    0.021496][    C0]  ? firmware_map_remove+0xee/0xee
> [    0.021496][    C0]  ? schedule+0xc9/0x160
> [    0.021496][    C0]  schedule+0x95/0x160
> [    0.021496][    C0]  do_boot_cpu+0x58c/0xaf0
> [    0.021496][    C0]  native_cpu_up+0x298/0x430
> [    0.021496][    C0]  ? common_cpu_up+0x150/0x150
> [    0.021496][    C0]  bringup_cpu+0x44/0x310
> [    0.021496][    C0]  ? timers_prepare_cpu+0x114/0x190
> [    0.021496][    C0]  ? takedown_cpu+0x2e0/0x2e0
> [    0.021496][    C0]  cpuhp_invoke_callback+0x197/0x1120
> [    0.021496][    C0]  ? ring_buffer_record_is_set_on+0x40/0x40
> [    0.021496][    C0]  _cpu_up+0x171/0x280
> [    0.021496][    C0]  do_cpu_up+0xb1/0x120
> [    0.021496][    C0]  cpu_up+0x13/0x20
> [    0.021496][    C0]  smp_init+0x91/0x118
> [    0.021496][    C0]  kernel_init_freeable+0x221/0x4f8
> [    0.021496][    C0]  ? mark_held_locks+0x34/0xb0
> [    0.021496][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
> [    0.021496][    C0]  ? start_kernel+0x857/0x857
> [    0.021496][    C0]  ? lockdep_hardirqs_on+0x1b0/0x2a0
> [    0.021496][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
> [    0.021496][    C0]  ? rest_init+0x307/0x307
> [    0.021496][    C0]  kernel_init+0x11/0x139
> [    0.021496][    C0]  ? rest_init+0x307/0x307
> [    0.021496][    C0]  ret_from_fork+0x27/0x50
> 
> [    0.021458][    C0] NMI watchdog: Watchdog detected hard LOCKUP on cpu 0
> [    0.021458][    C0] Modules linked in:
> [    0.021458][    C0] irq event stamp: 55574034
> [    0.021458][    C0] hardirqs last  enabled at (55574033): [<ffffffffa549d4d7>] _raw_spin_unlock_irq+0x27/0x40
> [    0.021458][    C0] hardirqs last disabled at (55574034): [<ffffffffa5491754>] __schedule+0x214/0x1070
> [    0.021458][    C0] softirqs last  enabled at (83640): [<ffffffffa5800447>] __do_softirq+0x447/0x766
> [    0.021458][    C0] softirqs last disabled at (83623): [<ffffffffa4ad2196>] irq_exit+0xd6/0xf0
> [    0.021458][    C0] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4+ #13
> [    0.021458][    C0] Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 03/09/2018
> [    0.021458][    C0] RIP: 0010:check_memory_region+0x136/0x200
> [    0.021458][    C0] Code: 00 eb 0c 49 83 c0 01 48 89 d8 49 39 d8 74 10 41 80 38 00 74 ee 4b 8d 44 0d 00 4d 85 c0 75 4d 4c 89 e3 48 29 c3 e9 3e ff ff ff <48> 85 db 74 2e 41 80 39 00 75 34 48 b8 01 00 00 00 00 fc ff df 49
> [    0.021458][    C0] RSP: 0018:ffffc900031779e8 EFLAGS: 00000083
> [    0.021458][    C0] RAX: fffff5200062ef48 RBX: 0000000000000001 RCX: ffffffffa4b94e16
> [    0.021458][    C0] RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90003177a40
> [    0.021458][    C0] RBP: ffffc90003177a00 R08: 1ffff9200062ef48 R09: fffff5200062ef48
> [    0.021458][    C0] R10: fffff5200062ef48 R11: ffffc90003177a43 R12: fffff5200062ef49
> [    0.021458][    C0] R13: ffffc90003177a80 R14: ffff888453444310 R15: ffff888453444308
> [    0.021458][    C0] FS:  0000000000000000(0000) GS:ffff888453400000(0000) knlGS:0000000000000000
> [    0.021458][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    0.021458][    C0] CR2: ffff88887b9ff000 CR3: 00000006e6c12000 CR4: 00000000003406f0
> [    0.021458][    C0] Call Trace:
> [    0.021458][    C0]  __kasan_check_write+0x14/0x20
> [    0.021458][    C0]  do_raw_spin_lock+0xe6/0x1e0
> [    0.021458][    C0]  ? rwlock_bug.part.1+0x60/0x60
> [    0.021458][    C0]  ? __schedule+0x227/0x1070
> [    0.021458][    C0]  _raw_spin_lock+0x37/0x40
> [    0.021458][    C0]  ? __schedule+0x227/0x1070
> [    0.021458][    C0]  __schedule+0x227/0x1070
> [    0.021458][    C0]  ? __sched_text_start+0x8/0x8
> [    0.021458][    C0]  schedule+0x95/0x160
> [    0.021458][    C0]  do_boot_cpu+0x58c/0xaf0
> [    0.021458][    C0]  native_cpu_up+0x298/0x430
> [    0.021458][    C0]  ? common_cpu_up+0x150/0x150
> [    0.021458][    C0]  bringup_cpu+0x44/0x310
> [    0.021458][    C0]  ? timers_prepare_cpu+0x114/0x190
> [    0.021458][    C0]  ? takedown_cpu+0x2e0/0x2e0
> [    0.021458][    C0]  cpuhp_invoke_callback+0x197/0x1120
> [    0.021458][    C0]  ? ring_buffer_record_is_set_on+0x40/0x40
> [    0.021458][    C0]  _cpu_up+0x171/0x280
> [    0.021458][    C0]  do_cpu_up+0xb1/0x120
> [    0.021458][    C0]  cpu_up+0x13/0x20
> [    0.021458][    C0]  smp_init+0x91/0x118
> [    0.021458][    C0]  kernel_init_freeable+0x221/0x4f8
> [    0.021458][    C0]  ? mark_held_locks+0x34/0xb0
> [    0.021458][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
> [    0.021458][    C0]  ? start_kernel+0x876/0x876
> [    0.021458][    C0]  ? lockdep_hardirqs_on+0x1b0/0x2a0
> [    0.021458][    C0]  ? _raw_spin_unlock_irq+0x27/0x40
> [    0.021458][    C0]  ? rest_init+0x307/0x307
> [    0.021458][    C0]  kernel_init+0x11/0x139
> [    0.021458][    C0]  ? rest_init+0x307/0x307
> [    0.021458][    C0]  ret_from_fork+0x27/0x50
> 
> 
> 


  parent reply	other threads:[~2020-03-19 13:58 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-06  4:06 PROVE_RCU_LIST + /proc/lockdep warning Qian Cai
2020-03-07  3:33 ` Hard lockups due to "tick/common: Make tick_periodic() check for missing ticks" Qian Cai
2020-03-08 21:18   ` Waiman Long
2020-03-19 13:58   ` Qian Cai [this message]
2020-03-19 19:00     ` Waiman Long
2020-03-20  2:00       ` Stephen Rothwell
2020-03-20 11:50         ` Thomas Gleixner
2020-03-07 17:16 ` PROVE_RCU_LIST + /proc/lockdep warning Joel Fernandes
2020-03-09  1:40   ` Boqun Feng
2020-03-10 18:42     ` Qian Cai
2020-03-11  3:30       ` Boqun Feng
2020-03-11 13:24         ` Qian Cai
2020-03-12  0:48           ` Boqun Feng

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