rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=558589, q=209) rcu: All QSes seen, last rcu_preempt kthread activity 10496 (4295239738-4295229242), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10496 jiffies! g558589 f0x2 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:28864 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4681 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5938 schedule+0xd3/0x270 kernel/sched/core.c:6017 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop kernel/rcu/tree.c:1996 [inline] rcu_gp_kthread+0xd34/0x1980 kernel/rcu/tree.c:2169 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: NMI backtrace for cpu 1 CPU: 1 PID: 29069 Comm: syz-executor.0 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 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+0x1d1/0x1d6 kernel/rcu/tree_stall.h:479 print_other_cpu_stall kernel/rcu/tree_stall.h:584 [inline] check_cpu_stall kernel/rcu/tree_stall.h:709 [inline] rcu_pending kernel/rcu/tree.c:3922 [inline] rcu_sched_clock_irq+0x2001/0x20c0 kernel/rcu/tree.c:2641 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:1537 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:199 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 ce 1a 2e f8 48 89 ef e8 76 90 2e f8 e8 41 c9 4e f8 fb bf 01 00 00 00 46 6e 22 f8 65 8b 05 ef e8 d4 76 85 c0 74 02 5d c3 e8 4b 3e d3 RSP: 0018:ffffc90000dc0e08 EFLAGS: 00000202 RAX: 00000000011da692 RBX: ffffffff874b6f90 RCX: 1ffffffff1fa1b1a RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000001 RBP: ffff8880b9d40240 R08: 0000000000000001 R09: ffffffff8fcd5937 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90000dc0e98 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8880b9d40240 expire_timers kernel/time/timer.c:1465 [inline] __run_timers.part.0+0x665/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x16e/0x1c0 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:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__sanitizer_cov_trace_switch+0xb8/0xf0 kernel/kcov.c:321 Code: 48 39 f7 72 1b 48 83 c2 01 48 89 5c 30 e0 48 89 6c 30 e8 4c 89 5c 30 f0 4e 89 4c e8 20 48 89 10 48 83 c1 01 49 39 ca 75 95 5b <5d> 41 5c 41 5d c3 48 83 f8 40 bb 07 00 00 00 0f 84 6c ff ff ff 5b RSP: 0018:ffffc90002fdf3c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffff888027a81c40 RDI: 0000000000000003 RBP: 0000000000000008 R08: ffffffff89dca1e0 R09: ffffffff839f3f99 R10: 0000000000000007 R11: 0000000000000002 R12: ffff888027a81c40 R13: 0000000000000151 R14: dffffc0000000000 R15: 0000000000000000 tomoyo_domain_quota_is_ok+0x1c9/0x550 security/tomoyo/util.c:1066 tomoyo_supervisor+0x2f2/0xf00 security/tomoyo/common.c:2089 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline] tomoyo_path_number_perm+0x419/0x590 security/tomoyo/file.c:734 tomoyo_path_mknod+0x10d/0x190 security/tomoyo/tomoyo.c:239 security_path_mknod+0xf9/0x170 security/security.c:1131 may_o_create fs/namei.c:3049 [inline] lookup_open.isra.0+0x475/0x13d0 fs/namei.c:3191 open_last_lookups fs/namei.c:3298 [inline] path_openat+0x9b3/0x27f0 fs/namei.c:3504 do_filp_open+0x1aa/0x400 fs/namei.c:3534 do_sys_openat2+0x16d/0x420 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_openat fs/open.c:1236 [inline] __se_sys_openat fs/open.c:1231 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231 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: 0033:0x4665e9 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:00007efd558cb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 00000000000026e1 RSI: 00000000200000c0 RDI: ffffffffffffff9c RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffbf1c4d7f R14: 00007efd558cb300 R15: 0000000000022000 ================================ WARNING: inconsistent lock state 5.14.0-rc5-syzkaller #0 Not tainted -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. syz-executor.0/29069 [HC0[0]:SC1[1]:HE0:SE0] takes: ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: print_other_cpu_stall kernel/rcu/tree_stall.h:543 [inline] ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: check_cpu_stall kernel/rcu/tree_stall.h:709 [inline] ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: rcu_pending kernel/rcu/tree.c:3922 [inline] ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: rcu_sched_clock_irq+0xc9a/0x20c0 kernel/rcu/tree.c:2641 {IN-HARDIRQ-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159 rcu_report_exp_cpu_mult+0x1c/0x280 kernel/rcu/tree_exp.h:237 flush_smp_call_function_queue+0x34b/0x640 kernel/smp.c:663 __sysvec_call_function_single+0x95/0x3d0 arch/x86/kernel/smp.c:248 sysvec_call_function_single+0x8e/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:646 rmqueue_pcplist mm/page_alloc.c:3678 [inline] rmqueue mm/page_alloc.c:3704 [inline] get_page_from_freelist+0x8c1/0x2f80 mm/page_alloc.c:4166 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391 alloc_pages_vma+0xd9/0x710 mm/mempolicy.c:2208 do_anonymous_page mm/memory.c:3767 [inline] handle_pte_fault mm/memory.c:4556 [inline] __handle_mm_fault+0x1f67/0x5320 mm/memory.c:4693 handle_mm_fault+0x1c8/0x790 mm/memory.c:4791 faultin_page mm/gup.c:951 [inline] __get_user_pages+0x806/0x1430 mm/gup.c:1173 __get_user_pages_locked mm/gup.c:1359 [inline] __get_user_pages_remote+0x18f/0x840 mm/gup.c:1865 get_user_pages_remote+0x63/0x90 mm/gup.c:1938 get_arg_page+0xba/0x200 fs/exec.c:220 copy_string_kernel+0x1b4/0x520 fs/exec.c:631 kernel_execve+0x25c/0x460 fs/exec.c:1961 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 irq event stamp: 18720403 hardirqs last enabled at (18720402): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (18720402): [] _raw_spin_unlock_irq+0x1f/0x40 kernel/locking/spinlock.c:199 hardirqs last disabled at (18720403): [] sysvec_apic_timer_interrupt+0xb/0xc0 arch/x86/kernel/apic/apic.c:1100 softirqs last enabled at (2200): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last enabled at (2200): [] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636 softirqs last disabled at (2381): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (2381): [] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(rcu_node_0); lock(rcu_node_0); *** DEADLOCK *** 4 locks held by syz-executor.0/29069: #0: ffff888147c7a460 (sb_writers#5){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3287 [inline] #0: ffff888147c7a460 (sb_writers#5){.+.+}-{0:0}, at: path_openat+0x25ed/0x27f0 fs/namei.c:3504 #1: ffff8880836f8e80 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #1: ffff8880836f8e80 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: open_last_lookups fs/namei.c:3295 [inline] #1: ffff8880836f8e80 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: path_openat+0x94d/0x27f0 fs/namei.c:3504 #2: ffffffff8c130cd8 (tomoyo_ss){....}-{0:0}, at: tomoyo_path_number_perm+0x18d/0x590 security/tomoyo/file.c:720 #3: ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: print_other_cpu_stall kernel/rcu/tree_stall.h:543 [inline] #3: ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: check_cpu_stall kernel/rcu/tree_stall.h:709 [inline] #3: ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: rcu_pending kernel/rcu/tree.c:3922 [inline] #3: ffffffff8b985018 (rcu_node_0){?.-.}-{2:2}, at: rcu_sched_clock_irq+0xc9a/0x20c0 kernel/rcu/tree.c:2641 stack backtrace: CPU: 1 PID: 29069 Comm: syz-executor.0 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_usage_bug kernel/locking/lockdep.c:203 [inline] valid_state kernel/locking/lockdep.c:3933 [inline] mark_lock_irq kernel/locking/lockdep.c:4136 [inline] mark_lock.cold+0x61/0x8e kernel/locking/lockdep.c:4593 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:4194 __trace_hardirqs_on_caller kernel/locking/lockdep.c:4212 [inline] lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4280 [inline] lockdep_hardirqs_on_prepare+0x135/0x400 kernel/locking/lockdep.c:4232 trace_hardirqs_on+0x5b/0x1c0 kernel/trace/trace_preemptirq.c:49 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:199 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 ce 1a 2e f8 48 89 ef e8 76 90 2e f8 e8 41 c9 4e f8 fb bf 01 00 00 00 46 6e 22 f8 65 8b 05 ef e8 d4 76 85 c0 74 02 5d c3 e8 4b 3e d3 RSP: 0018:ffffc90000dc0e08 EFLAGS: 00000202 RAX: 00000000011da692 RBX: ffffffff874b6f90 RCX: 1ffffffff1fa1b1a RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000001 RBP: ffff8880b9d40240 R08: 0000000000000001 R09: ffffffff8fcd5937 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90000dc0e98 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8880b9d40240 expire_timers kernel/time/timer.c:1465 [inline] __run_timers.part.0+0x665/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x16e/0x1c0 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:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__sanitizer_cov_trace_switch+0xb8/0xf0 kernel/kcov.c:321 Code: 48 39 f7 72 1b 48 83 c2 01 48 89 5c 30 e0 48 89 6c 30 e8 4c 89 5c 30 f0 4e 89 4c e8 20 48 89 10 48 83 c1 01 49 39 ca 75 95 5b <5d> 41 5c 41 5d c3 48 83 f8 40 bb 07 00 00 00 0f 84 6c ff ff ff 5b RSP: 0018:ffffc90002fdf3c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffff888027a81c40 RDI: 0000000000000003 RBP: 0000000000000008 R08: ffffffff89dca1e0 R09: ffffffff839f3f99 R10: 0000000000000007 R11: 0000000000000002 R12: ffff888027a81c40 R13: 0000000000000151 R14: dffffc0000000000 R15: 0000000000000000 tomoyo_domain_quota_is_ok+0x1c9/0x550 security/tomoyo/util.c:1066 tomoyo_supervisor+0x2f2/0xf00 security/tomoyo/common.c:2089 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline] tomoyo_path_number_perm+0x419/0x590 security/tomoyo/file.c:734 tomoyo_path_mknod+0x10d/0x190 security/tomoyo/tomoyo.c:239 security_path_mknod+0xf9/0x170 security/security.c:1131 may_o_create fs/namei.c:3049 [inline] lookup_open.isra.0+0x475/0x13d0 fs/namei.c:3191 open_last_lookups fs/namei.c:3298 [inline] path_openat+0x9b3/0x27f0 fs/namei.c:3504 do_filp_open+0x1aa/0x400 fs/namei.c:3534 do_sys_openat2+0x16d/0x420 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_openat fs/open.c:1236 [inline] __se_sys_openat fs/open.c:1231 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231 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: 0033:0x4665e9 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:00007efd558cb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 00000000000026e1 RSI: 00000000200000c0 RDI: ffffffffffffff9c RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffbf1c4d7f R14: 00007efd558cb300 R15: 0000000000022000 softirq: huh, entered softirq 1 TIMER ffffffff816505a0 with preempt_count 00000100, exited with 00000101?