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INFO: rcu detected stall in sys_futex (4)

Status: closed as invalid on 2022/02/08 10:00
Subsystems: kernel
[Documentation on labels]
First crash: 1096d, last: 1096d
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_futex (7) kernel 65 10d 218d 0/28 upstream: reported on 2024/06/24 16:48
upstream INFO: rcu detected stall in sys_futex (3) kernel 959 1847d 1896d 0/28 auto-closed as invalid on 2020/03/08 12:44
upstream INFO: rcu detected stall in sys_futex (2) kernel 6 2015d 2159d 0/28 auto-closed as invalid on 2019/10/25 14:11
linux-5.15 INFO: rcu detected stall in sys_futex (2) origin:lts-only syz error 12 26d 237d 0/3 upstream: reported syz repro on 2024/06/05 16:49
upstream INFO: rcu detected stall in sys_futex kernel 1 2221d 2221d 0/28 closed as invalid on 2018/12/31 04:10
linux-5.15 INFO: rcu detected stall in sys_futex 4 393d 567d 0/3 auto-obsoleted due to no activity on 2024/04/10 17:08
linux-6.1 INFO: rcu detected stall in sys_futex 17 20d 573d 0/3 upstream: reported on 2023/07/05 11:35
upstream INFO: rcu detected stall in sys_futex (5) kernel 12 827d 1072d 0/28 auto-obsoleted due to no activity on 2023/02/12 18:33
upstream INFO: rcu detected stall in sys_futex (6) kernel 10 395d 631d 0/28 auto-obsoleted due to no activity on 2024/03/29 00:57

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=e9b/1/0x4000000000000000 softirq=75039/75039 fqs=7 
	(detected by 1, t=10502 jiffies, g=93857, q=60)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 17380 Comm: syz-executor.2 Not tainted 5.17.0-rc1-syzkaller-00186-g23a46422c561 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:iterate_chain_key kernel/locking/lockdep.c:421 [inline]
RIP: 0010:__lock_acquire+0xc67/0x5470 kernel/locking/lockdep.c:5015
Code: c8 c1 c6 10 31 f0 8d 34 11 89 c1 29 c2 c1 c9 0d 01 f0 89 f7 31 ca 01 d0 29 d7 89 d1 48 8b 54 24 38 c1 c1 04 31 f9 48 c1 e1 20 <48> 09 c1 48 c1 ea 03 48 b8 00 00 00 00 00 fc ff df 0f b6 04 02 48
RSP: 0018:ffffc90000007bf8 EFLAGS: 00000896
RAX: 00000000ae833244 RBX: ffffffff8ffd8260 RCX: cd16587000000000
RDX: ffff88801f2be180 RSI: 00000000ffe8de65 RDI: 00000000474380db
RBP: ffff88801f2be182 R08: 0000000000000000 R09: ffffffff8ffd394f
R10: fffffbfff1ffa729 R11: 0000000000000001 R12: ffff88801f2be160
R13: ffff88801f2bd700 R14: ffffffff8d94faa8 R15: 0000000000000001
FS:  00005555558eb400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000073467000 CR4: 0000000000350ef0
DR0: 0800000000000080 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x243/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 2a 61 0c f8 48 89 ef e8 e2 d6 0c f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 13 8a ff f7 65 8b 05 cc 8e b1 76 85 c0 74 0a 5b 5d c3 e8 a0 c1
RSP: 0018:ffffc90003b47b98 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff1b29369
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffff888077332680 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff817ea2d8 R11: 0000000000000000 R12: 0000000000000206
R13: ffff888077331d14 R14: ffff888077332680 R15: ffff8880b9c39c40
 try_to_wake_up+0x560/0x1510 kernel/sched/core.c:4135
 wake_up_process kernel/sched/core.c:4217 [inline]
 wake_up_q+0x7e/0xf0 kernel/sched/core.c:964
 futex_wake+0x3e9/0x490 kernel/futex/waitwake.c:184
 do_futex+0x266/0x300 kernel/futex/syscalls.c:111
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex kernel/futex/syscalls.c:164 [inline]
 __x64_sys_futex+0x1b0/0x4a0 kernel/futex/syscalls.c:164
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7efd05c5d059
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff41322f78 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007efd05d7003c RCX: 00007efd05c5d059
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007efd05d70038
RBP: 00007efd05d6ff60 R08: 0000000000000000 R09: 00000000000000d0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007efd05d7003c
R13: 00007efd05d75818 R14: 00007efd05d70030 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread starved for 10488 jiffies! g93857 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28736 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 17382 Comm: syz-executor.2 Not tainted 5.17.0-rc1-syzkaller-00186-g23a46422c561 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:458
 print_other_cpu_stall kernel/rcu/tree_stall.h:563 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:706 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq+0x1f7c/0x2150 kernel/rcu/tree.c:2617
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0x447/0xc90 kernel/smp.c:969
Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 fb 7d 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 95 06 00 00 8b 43 08 31
RSP: 0018:ffffc90003b9fae0 EFLAGS: 00000246
RAX: 0000000000040000 RBX: ffff8880b9c41fa0 RCX: ffffc90002d01000
RDX: 0000000000040000 RSI: ffffffff816cdf55 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff816cdf7b R11: 0000000000000000 R12: ffffed10173883f5
R13: 0000000000000000 R14: ffff8880b9c41fa8 R15: 0000000000000001
 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1135
 kill_bdev block/bdev.c:76 [inline]
 set_blocksize+0x2b3/0x370 block/bdev.c:153
 sb_set_blocksize+0x49/0x110 block/bdev.c:162
 minix_fill_super+0x9e/0x1bd0 fs/minix/inode.c:191
 mount_bdev+0x34d/0x410 fs/super.c:1367
 legacy_get_tree+0x105/0x220 fs/fs_context.c:610
 vfs_get_tree+0x89/0x2f0 fs/super.c:1497
 do_new_mount fs/namespace.c:2994 [inline]
 path_mount+0x1320/0x1fa0 fs/namespace.c:3324
 do_mount fs/namespace.c:3337 [inline]
 __do_sys_mount fs/namespace.c:3545 [inline]
 __se_sys_mount fs/namespace.c:3522 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3522
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7efd05c5e58a
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efd045d1f88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000180 RCX: 00007efd05c5e58a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007efd045d1fe0
RBP: 00007efd045d2020 R08: 00007efd045d2020 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007efd045d1fe0 R15: 0000000020000200
 </TASK>
----------------
Code disassembly (best guess):
   0:	c8 c1 c6 10          	enterq $0xc6c1,$0x10
   4:	31 f0                	xor    %esi,%eax
   6:	8d 34 11             	lea    (%rcx,%rdx,1),%esi
   9:	89 c1                	mov    %eax,%ecx
   b:	29 c2                	sub    %eax,%edx
   d:	c1 c9 0d             	ror    $0xd,%ecx
  10:	01 f0                	add    %esi,%eax
  12:	89 f7                	mov    %esi,%edi
  14:	31 ca                	xor    %ecx,%edx
  16:	01 d0                	add    %edx,%eax
  18:	29 d7                	sub    %edx,%edi
  1a:	89 d1                	mov    %edx,%ecx
  1c:	48 8b 54 24 38       	mov    0x38(%rsp),%rdx
  21:	c1 c1 04             	rol    $0x4,%ecx
  24:	31 f9                	xor    %edi,%ecx
  26:	48 c1 e1 20          	shl    $0x20,%rcx
* 2a:	48 09 c1             	or     %rax,%rcx <-- trapping instruction
  2d:	48 c1 ea 03          	shr    $0x3,%rdx
  31:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  38:	fc ff df
  3b:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/01/28 06:52 upstream 23a46422c561 495e00c5 .config console log report info ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_futex
* Struck through repros no longer work on HEAD.