syzbot


INFO: rcu detected stall in fork

Status: closed as invalid on 2022/02/08 10:10
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 333d, last: 333d

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=4ef/1/0x4000000000000000 softirq=95713/95714 fqs=0 
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P2765/1:b..l
	(detected by 0, t=10502 jiffies, g=155721, q=32)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2764 Comm: syz-executor.4 Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
RIP: 0010:do_raw_spin_lock+0xa9/0x2b0 kernel/locking/spinlock_debug.c:114
Code: 01 00 00 8b 45 04 3d ad 4e ad de 0f 85 77 01 00 00 4c 8d 6d 10 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 <0f> 85 ba 01 00 00 48 8b 55 10 65 48 8b 04 25 40 70 02 00 48 39 c2
RSP: 0018:ffffc90000fd8da8 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 1ffff920001fb1b6 RCX: 0000000000000000
RDX: 1ffff110173a5482 RSI: 0000000000010002 RDI: ffff8880b9d2a404
RBP: ffff8880b9d2a400 R08: 0000000000000000 R09: ffffffff8ff7aa0f
R10: fffffbfff1fef541 R11: 0000000000000001 R12: 0000000000000000
R13: ffff8880b9d2a410 R14: ffff8880b9d2a400 R15: 0000000000000001
FS:  00007f8bab1f2700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8bac991090 CR3: 000000001cc28000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __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:__sanitizer_cov_trace_pc+0x59/0x60 kernel/kcov.c:208
Code: 74 2b 8b 82 80 15 00 00 83 f8 02 75 20 48 8b 8a 88 15 00 00 8b 92 84 15 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 34 c1 <48> 89 01 c3 0f 1f 00 41 55 41 54 49 89 fc 55 48 bd eb 83 b5 80 46
RSP: 0018:ffffc9000fd6f900 EFLAGS: 00000212
RAX: 000000000000010f RBX: ffff888015fa3250 RCX: ffffc90010b2e000
RDX: 0000000000040000 RSI: ffffffff81b1ad1b RDI: 0000000000000003
RBP: ffffc90001030000 R08: ffffc90001030000 R09: 0000000000000003
R10: ffffffff81b1ad0c R11: 0000000000000001 R12: ffffc9000102f000
R13: ffffc90001039000 R14: ffffc90000000000 R15: dffffc0000000000
 is_within_this_va mm/vmalloc.c:1180 [inline]
 find_vmap_lowest_match mm/vmalloc.c:1230 [inline]
 __alloc_vmap_area mm/vmalloc.c:1437 [inline]
 alloc_vmap_area+0x44b/0x1dc0 mm/vmalloc.c:1547
 __get_vm_area_node.constprop.0+0x128/0x380 mm/vmalloc.c:2434
 __vmalloc_node_range+0x12c/0xab0 mm/vmalloc.c:3055
 alloc_thread_stack_node kernel/fork.c:244 [inline]
 dup_task_struct kernel/fork.c:886 [inline]
 copy_process+0x926/0x75a0 kernel/fork.c:2023
 kernel_clone+0xe7/0xab0 kernel/fork.c:2582
 __do_sys_fork+0x8a/0xc0 kernel/fork.c:2645
 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: 0033:0x7f8bac87ce99
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:00007f8bab1f2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000039
RAX: ffffffffffffffda RBX: 00007f8bac98ff60 RCX: 00007f8bac87ce99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8bac8d6ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffecc8c4bdf R14: 00007f8bab1f2300 R15: 0000000000022000
 </TASK>
task:syz-executor.1  state:R  running task     stack:29024 pid: 2765 ppid:  3705 flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6668
 irqentry_exit+0x31/0x80 kernel/entry/common.c:425
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:200
Code: 45 00 5d be 03 00 00 00 e9 d6 39 64 02 66 0f 1f 44 00 00 48 8b be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 65 8b 05 f9 a7 8b 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 40 70 02 00 a9
RSP: 0018:ffffc9000fdbf8d8 EFLAGS: 00000282
RAX: 0000000080000000 RBX: ffffc9000fdbfb88 RCX: 0000000000000000
RDX: ffff888055f1c080 RSI: ffffffff83a30c7f RDI: ffffc9000fdbfb88
RBP: ffffc9000fdbfb88 R08: 0000000000000000 R09: ffffc9000fdbfb88
R10: ffffffff83a509d5 R11: 00000000000003f1 R12: ffff88807f3d8000
R13: 00000000000000ec R14: ffff88807f140008 R15: dffffc0000000000
 context_compute_hash+0xf/0x2a0 security/selinux/ss/context.c:26
 sidtab_context_to_sid+0x27/0x1100 security/selinux/ss/sidtab.c:268
 security_compute_sid.part.0+0xb61/0x15f0 security/selinux/ss/services.c:1904
 security_compute_sid security/selinux/ss/services.c:1936 [inline]
 security_transition_sid+0xbc/0x190 security/selinux/ss/services.c:1936
 selinux_determine_inode_label+0x256/0x340 security/selinux/hooks.c:1808
 may_create+0x24f/0x370 security/selinux/hooks.c:1843
 security_inode_symlink+0x9a/0x100 security/security.c:1251
 vfs_symlink fs/namei.c:4244 [inline]
 vfs_symlink+0x3f4/0x6c0 fs/namei.c:4233
 do_symlinkat+0x261/0x2e0 fs/namei.c:4277
 __do_sys_symlink fs/namei.c:4299 [inline]
 __se_sys_symlink fs/namei.c:4297 [inline]
 __x64_sys_symlink+0x75/0x90 fs/namei.c:4297
 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: 0033:0x7f3e8ad807a7
RSP: 002b:00007fff2a9c4858 EFLAGS: 00000202 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3e8ad807a7
RDX: 00007fff2a9c4933 RSI: 00007f3e8addb0a6 RDI: 00007fff2a9c4920
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff2a9c46f0
R10: 00007fff2a9c45a7 R11: 0000000000000202 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007fff2a9c4920
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g155721 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:28888 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
 kthread+0x405/0x4f0 kernel/kthread.c:327
 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 0
CPU: 0 PID: 346 Comm: syz-executor.2 Not tainted 5.16.0-rc8-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: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:481
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq+0x1f7c/0x2150 kernel/rcu/tree.c:2597
 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:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1001
Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 e3 81 49 00 eb 07 0f 00 2d 1a 8f 75 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 a6 7c 49 00 8b 74 24 0c
RSP: 0018:ffffc900041477b8 EFLAGS: 00000202
RAX: 000000000017a9fb RBX: 0000000000000000 RCX: 1ffffffff1fefb56
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8bc9e7c0 R08: 0000000000000001 R09: ffffffff8ff7aa07
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: fffffbfff1793cf8 R14: 0000000000000001 R15: ffff8880b9c3a900
 pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x8b8/0xb40 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [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:349 [inline]
 preload_this_cpu_lock mm/vmalloc.c:1504 [inline]
 alloc_vmap_area+0xb13/0x1dc0 mm/vmalloc.c:1546
 __get_vm_area_node.constprop.0+0x128/0x380 mm/vmalloc.c:2434
 __vmalloc_node_range+0x12c/0xab0 mm/vmalloc.c:3055
 __vmalloc_node mm/vmalloc.c:3114 [inline]
 vzalloc+0x67/0x80 mm/vmalloc.c:3184
 do_arpt_get_ctl+0x5f0/0x8f0 net/ipv4/netfilter/arp_tables.c:660
 nf_getsockopt+0x72/0xd0 net/netfilter/nf_sockopt.c:116
 ip_getsockopt net/ipv4/ip_sockglue.c:1786 [inline]
 ip_getsockopt+0x164/0x1c0 net/ipv4/ip_sockglue.c:1765
 tcp_getsockopt+0x86/0xd0 net/ipv4/tcp.c:4251
 __sys_getsockopt+0x21f/0x5f0 net/socket.c:2220
 __do_sys_getsockopt net/socket.c:2235 [inline]
 __se_sys_getsockopt net/socket.c:2232 [inline]
 __x64_sys_getsockopt+0xba/0x150 net/socket.c:2232
 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: 0033:0x7f6a3364e4ba
Code: 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 37 00 00 00 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:00007fffaa0999a8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007fffaa0999bc RCX: 00007f6a3364e4ba
RDX: 0000000000000061 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fffaa0999bc R09: ffffffffff000000
R10: 00007fffaa099a10 R11: 0000000000000212 R12: 00007fffaa099a10
R13: 000000000011b80e R14: 000000000000000b R15: 00007fffaa09a120
 </TASK>
----------------
Code disassembly (best guess):
   0:	01 00                	add    %eax,(%rax)
   2:	00 8b 45 04 3d ad    	add    %cl,-0x52c2fbbb(%rbx)
   8:	4e ad                	rex.WRX lods %ds:(%rsi),%rax
   a:	de 0f                	fimuls (%rdi)
   c:	85 77 01             	test   %esi,0x1(%rdi)
   f:	00 00                	add    %al,(%rax)
  11:	4c 8d 6d 10          	lea    0x10(%rbp),%r13
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	4c 89 ea             	mov    %r13,%rdx
  22:	48 c1 ea 03          	shr    $0x3,%rdx
  26:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
* 2a:	0f 85 ba 01 00 00    	jne    0x1ea <-- trapping instruction
  30:	48 8b 55 10          	mov    0x10(%rbp),%rdx
  34:	65 48 8b 04 25 40 70 	mov    %gs:0x27040,%rax
  3b:	02 00
  3d:	48 39 c2             	cmp    %rax,%rdx

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2022/01/03 07:07 upstream c9e6606c7fe9 e1768e9c .config log report info INFO: rcu detected stall in fork
* Struck through repros no longer work on HEAD.