syzbot


INFO: rcu detected stall in sys_pselect6

Status: auto-closed as invalid on 2021/12/05 02:59
Subsystems: fs
[Documentation on labels]
First crash: 971d, last: 971d

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10462 ticks this GP) idle=3e1/1/0x4000000000000000 softirq=163778/163784 fqs=0 
	(t=10501 jiffies g=251497 q=28)
rcu: rcu_preempt kthread starved for 10502 jiffies! g251497 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:
 context_switch kernel/sched/core.c:4940 [inline]
 __schedule+0x940/0x26f0 kernel/sched/core.c:6287
 schedule+0xd3/0x270 kernel/sched/core.c:6366
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 23441 Comm: syz-executor.5 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:native_apic_mem_write+0x8/0x10 arch/x86/include/asm/apic.h:110
Code: c7 40 f7 ee 8e e8 28 3b 8a 00 eb b0 66 0f 1f 44 00 00 be 01 00 00 00 e9 e6 1e 2d 00 cc cc cc cc cc cc 89 ff 89 b7 00 c0 5f ff <c3> 0f 1f 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 53 89 fb 48
RSP: 0018:ffffc90000007fd0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff8b337a60 RCX: 1ffff11017383f0c
RDX: 1ffffffff1666f4c RSI: 0000000000000000 RDI: 00000000000000b0
RBP: 0000000000000000 R08: ffffffff8eefa018 R09: ffffffff8eefa00f
R10: ffffffff8eefa017 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f99e6120700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ed95088458 CR3: 000000006a2b8000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 apic_eoi arch/x86/include/asm/apic.h:399 [inline]
 ack_APIC_irq arch/x86/include/asm/apic.h:445 [inline]
 __sysvec_apic_timer_interrupt+0x79/0x530 arch/x86/kernel/apic/apic.c:1101
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:434 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3ba/0xb40 kernel/locking/qspinlock.c:508
Code: eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c f3 90 <41> 83 ec 01 0f 84 72 04 00 00 41 0f b6 45 00 38 d8 7f 08 84 c0 0f
RSP: 0018:ffffc9000385f568 EFLAGS: 00000206
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff1769a0c
RDX: 0000000000000001 RSI: ffffffff817c49b1 RDI: ffffffff81334591
RBP: ffffffff8bb4d060 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff817c4979 R11: 0000000000000000 R12: 0000000000004a2a
R13: fffffbfff1769a0c R14: 0000000000000001 R15: ffff8880b9c327c0
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:363 [inline]
 sysctl_head_grab+0x20/0xb0 fs/proc/proc_sysctl.c:306
 grab_header fs/proc/proc_sysctl.c:492 [inline]
 proc_sys_poll+0x7c/0x440 fs/proc/proc_sysctl.c:635
 vfs_poll include/linux/poll.h:90 [inline]
 do_select+0x8cb/0x16a0 fs/select.c:534
 core_sys_select+0x3c2/0x9c0 fs/select.c:677
 do_pselect.constprop.0+0x17b/0x1c0 fs/select.c:759
 __do_sys_pselect6 fs/select.c:800 [inline]
 __se_sys_pselect6 fs/select.c:791 [inline]
 __x64_sys_pselect6+0x1c5/0x2b0 fs/select.c:791
 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: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f99e6120188 EFLAGS: 00000246 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000040
RBP: 00000000004bfcc4 R08: 0000000020000200 R09: 0000000000000000
R10: 0000000020000140 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffd09146c9f R14: 00007f99e6120300 R15: 0000000000022000
NMI backtrace for cpu 1
CPU: 1 PID: 23446 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #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:105
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:711 [inline]
 rcu_pending kernel/rcu/tree.c:3880 [inline]
 rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599
 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:1421
 __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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:mac80211_hwsim_tx_frame_no_nl.isra.0+0xa37/0x1330 drivers/net/wireless/mac80211_hwsim.c:1537
Code: 7f 04 41 8b 55 04 48 89 f8 48 c1 e8 03 0f b6 0c 28 48 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85 b3 07 00 00 45 8b 7f 04 <89> d7 89 54 24 08 44 89 fe e8 2b b3 3f fc 8b 54 24 08 44 39 fa 74
RSP: 0018:ffffc90000dc0ba0 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff88801d3eb2a0 RCX: 0000000000000000
RDX: 000000000000096c RSI: ffffffff853675e6 RDI: ffff88801d3eb4d4
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff85367445
R10: ffffffff85367503 R11: 0000000000000000 R12: ffff88803f5ef140
R13: ffff888021d734d0 R14: ffff888021d732a0 R15: 000000000000096c
 mac80211_hwsim_tx_frame+0x1ee/0x2a0 drivers/net/wireless/mac80211_hwsim.c:1784
 mac80211_hwsim_beacon_tx+0x49b/0x930 drivers/net/wireless/mac80211_hwsim.c:1838
 __iterate_interfaces+0x1e5/0x520 net/mac80211/util.c:793
 ieee80211_iterate_active_interfaces_atomic+0x70/0x180 net/mac80211/util.c:829
 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1861
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:spin_unlock include/linux/spinlock.h:403 [inline]
RIP: 0010:sysctl_head_finish fs/proc/proc_sysctl.c:319 [inline]
RIP: 0010:sysctl_head_finish fs/proc/proc_sysctl.c:313 [inline]
RIP: 0010:proc_sys_poll+0x2cc/0x440 fs/proc/proc_sysctl.c:659
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 4f 01 00 00 48 8b 6b 18 48 85 ed 0f 85 be 00 00 00 e8 8b 27 83 ff 48 c7 c7 60 d0 b4 8b <e8> ff 79 44 07 e8 7a 27 83 ff 44 89 e0 48 83 c4 20 5b 5d 41 5c 41
RSP: 0018:ffffc900031df6e8 EFLAGS: 00000212
RAX: 0000000000025d52 RBX: ffff88807c5b8000 RCX: ffffc900017c1000
RDX: 0000000000040000 RSI: ffffffff81f2f9b5 RDI: ffffffff8bb4d060
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000003
R10: ffffffff81f2f97b R11: 0000000000000000 R12: 0000000000000145
R13: ffffc900031df898 R14: 0000000000000000 R15: ffff88807900d7a8
 vfs_poll include/linux/poll.h:90 [inline]
 do_select+0x8cb/0x16a0 fs/select.c:534
 core_sys_select+0x3c2/0x9c0 fs/select.c:677
 do_pselect.constprop.0+0x17b/0x1c0 fs/select.c:759
 __do_sys_pselect6 fs/select.c:800 [inline]
 __se_sys_pselect6 fs/select.c:791 [inline]
 __x64_sys_pselect6+0x1c5/0x2b0 fs/select.c:791
 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: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f755c0c0188 EFLAGS: 00000246 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000040
RBP: 00000000004bfcc4 R08: 0000000020000200 R09: 0000000000000000
R10: 0000000020000140 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffd1b8a707f R14: 00007f755c0c0300 R15: 0000000000022000
----------------
Code disassembly (best guess):
   0:	c7 40 f7 ee 8e e8 28 	movl   $0x28e88eee,-0x9(%rax)
   7:	3b 8a 00 eb b0 66    	cmp    0x66b0eb00(%rdx),%ecx
   d:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  12:	be 01 00 00 00       	mov    $0x1,%esi
  17:	e9 e6 1e 2d 00       	jmpq   0x2d1f02
  1c:	cc                   	int3
  1d:	cc                   	int3
  1e:	cc                   	int3
  1f:	cc                   	int3
  20:	cc                   	int3
  21:	cc                   	int3
  22:	89 ff                	mov    %edi,%edi
  24:	89 b7 00 c0 5f ff    	mov    %esi,-0xa04000(%rdi)
* 2a:	c3                   	retq <-- trapping instruction
  2b:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  32:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  39:	fc ff df
  3c:	53                   	push   %rbx
  3d:	89 fb                	mov    %edi,%ebx
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/09/06 02:51 upstream 0319b848b155 d236a457 .config console log report info ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_pselect6
* Struck through repros no longer work on HEAD.