====================================================== WARNING: possible circular locking dependency detected 4.20.0-next-20190103 #5 Not tainted ------------------------------------------------------ syz-executor0/18110 is trying to acquire lock: 00000000f185317d (&pgdat->kswapd_wait){....}, at: __wake_up_common_lock+0x19b/0x390 kernel/sched/wait.c:120 but task is already holding lock: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:329 [inline] 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_bulk mm/page_alloc.c:2665 [inline] 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: __rmqueue_pcplist mm/page_alloc.c:3138 [inline] 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_pcplist mm/page_alloc.c:3167 [inline] 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue mm/page_alloc.c:3189 [inline] 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: get_page_from_freelist+0x1ab1/0x50f0 mm/page_alloc.c:3608 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&(&zone->lock)->rlock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 rmqueue mm/page_alloc.c:3199 [inline] get_page_from_freelist+0x13d0/0x50f0 mm/page_alloc.c:3608 __alloc_pages_nodemask+0x4fd/0xdc0 mm/page_alloc.c:4646 alloc_pages_current+0x107/0x210 mm/mempolicy.c:2106 alloc_pages include/linux/gfp.h:509 [inline] depot_save_stack+0x3da/0x460 lib/stackdepot.c:260 save_stack+0xa9/0xd0 mm/kasan/common.c:79 set_track mm/kasan/common.c:85 [inline] kasan_kmalloc mm/kasan/common.c:482 [inline] kasan_kmalloc+0xcf/0xe0 mm/kasan/common.c:455 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:397 slab_post_alloc_hook mm/slab.h:444 [inline] slab_alloc mm/slab.c:3379 [inline] kmem_cache_alloc+0x11a/0x710 mm/slab.c:3539 kmem_cache_zalloc include/linux/slab.h:730 [inline] fill_pool lib/debugobjects.c:134 [inline] __debug_object_init+0xb6b/0x1280 lib/debugobjects.c:380 debug_object_init lib/debugobjects.c:436 [inline] debug_object_activate+0x32f/0x4e0 lib/debugobjects.c:518 debug_timer_activate kernel/time/timer.c:708 [inline] debug_activate kernel/time/timer.c:763 [inline] __mod_timer kernel/time/timer.c:1040 [inline] mod_timer kernel/time/timer.c:1101 [inline] add_timer+0x4e6/0x1470 kernel/time/timer.c:1137 __queue_delayed_work+0x253/0x390 kernel/workqueue.c:1533 queue_delayed_work_on+0x19a/0x200 kernel/workqueue.c:1558 queue_delayed_work include/linux/workqueue.h:527 [inline] schedule_delayed_work include/linux/workqueue.h:628 [inline] unaccount_event kernel/events/core.c:4311 [inline] _free_event+0xee1/0x1640 kernel/events/core.c:4419 put_event+0x47/0x60 kernel/events/core.c:4532 perf_event_release_kernel+0x890/0xf70 kernel/events/core.c:4638 perf_release+0x37/0x50 kernel/events/core.c:4648 __fput+0x3c5/0xb10 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x1f4/0x2b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x32a/0x3b0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #3 (&base->lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 lock_timer_base+0xb7/0x2a0 kernel/time/timer.c:937 __mod_timer kernel/time/timer.c:1009 [inline] mod_timer kernel/time/timer.c:1101 [inline] add_timer+0x884/0x1470 kernel/time/timer.c:1137 __queue_delayed_work+0x253/0x390 kernel/workqueue.c:1533 queue_delayed_work_on+0x19a/0x200 kernel/workqueue.c:1558 queue_delayed_work include/linux/workqueue.h:527 [inline] schedule_delayed_work include/linux/workqueue.h:628 [inline] psi_group_change kernel/sched/psi.c:485 [inline] psi_task_change+0x3ea/0x590 kernel/sched/psi.c:534 psi_enqueue kernel/sched/stats.h:82 [inline] enqueue_task kernel/sched/core.c:727 [inline] activate_task+0x1f8/0x470 kernel/sched/core.c:751 wake_up_new_task+0x50c/0xd30 kernel/sched/core.c:2423 _do_fork+0x2a5/0x1170 kernel/fork.c:2241 kernel_thread+0x34/0x40 kernel/fork.c:2275 rest_init+0x28/0x37b init/main.c:408 arch_call_rest_init+0xe/0x1b start_kernel+0x882/0x8bd init/main.c:740 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:470 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #2 (&rq->lock){-.-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:144 rq_lock kernel/sched/sched.h:1149 [inline] task_fork_fair+0xb5/0x7a0 kernel/sched/fair.c:10058 sched_fork+0x437/0xb90 kernel/sched/core.c:2359 copy_process+0x1ff6/0x8720 kernel/fork.c:1887 _do_fork+0x1a9/0x1170 kernel/fork.c:2216 kernel_thread+0x34/0x40 kernel/fork.c:2275 rest_init+0x28/0x37b init/main.c:408 arch_call_rest_init+0xe/0x1b start_kernel+0x882/0x8bd init/main.c:740 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:470 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #1 (&p->pi_lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 try_to_wake_up+0xb9/0x1480 kernel/sched/core.c:1965 default_wake_function+0x30/0x50 kernel/sched/core.c:3710 autoremove_wake_function+0x79/0x360 kernel/sched/wait.c:375 __wake_up_common+0x1d3/0x7d0 kernel/sched/wait.c:92 __wake_up_common_lock+0x1c6/0x390 kernel/sched/wait.c:121 __wake_up+0xe/0x10 kernel/sched/wait.c:145 wakeup_kswapd+0x5ba/0x8f0 mm/vmscan.c:4001 wake_all_kswapds+0x14d/0x300 mm/page_alloc.c:4092 __alloc_pages_slowpath+0x1ecf/0x2cc0 mm/page_alloc.c:4363 __alloc_pages_nodemask+0xa37/0xdc0 mm/page_alloc.c:4666 __alloc_pages include/linux/gfp.h:473 [inline] __alloc_pages_node include/linux/gfp.h:486 [inline] alloc_new_node_page mm/mempolicy.c:951 [inline] alloc_new_node_page+0x438/0x510 mm/mempolicy.c:935 unmap_and_move mm/migrate.c:1177 [inline] migrate_pages+0x494/0x2cc0 mm/migrate.c:1428 migrate_to_node mm/mempolicy.c:979 [inline] do_migrate_pages+0x526/0x740 mm/mempolicy.c:1080 kernel_migrate_pages+0x5af/0x740 mm/mempolicy.c:1460 __do_sys_migrate_pages mm/mempolicy.c:1479 [inline] __se_sys_migrate_pages mm/mempolicy.c:1475 [inline] __x64_sys_migrate_pages+0x97/0xf0 mm/mempolicy.c:1475 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&pgdat->kswapd_wait){....}: lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 __wake_up_common_lock+0x19b/0x390 kernel/sched/wait.c:120 __wake_up+0xe/0x10 kernel/sched/wait.c:145 wakeup_kswapd+0x5ba/0x8f0 mm/vmscan.c:4001 steal_suitable_fallback+0x50d/0x7c0 mm/page_alloc.c:2334 __rmqueue_fallback mm/page_alloc.c:2619 [inline] __rmqueue mm/page_alloc.c:2645 [inline] rmqueue_bulk mm/page_alloc.c:2667 [inline] __rmqueue_pcplist mm/page_alloc.c:3138 [inline] rmqueue_pcplist mm/page_alloc.c:3167 [inline] rmqueue mm/page_alloc.c:3189 [inline] get_page_from_freelist+0x2f53/0x50f0 mm/page_alloc.c:3608 __alloc_pages_nodemask+0x4fd/0xdc0 mm/page_alloc.c:4646 alloc_pages_vma+0xdd/0x540 mm/mempolicy.c:2070 alloc_zeroed_user_highpage_movable include/linux/highmem.h:208 [inline] do_anonymous_page mm/memory.c:2934 [inline] handle_pte_fault mm/memory.c:3779 [inline] __handle_mm_fault+0x2537/0x55a0 mm/memory.c:3905 handle_mm_fault+0x4ec/0xc80 mm/memory.c:3942 do_user_addr_fault arch/x86/mm/fault.c:1475 [inline] __do_page_fault+0x5da/0xd60 arch/x86/mm/fault.c:1541 do_page_fault+0xe6/0x7d8 arch/x86/mm/fault.c:1572 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1143 other info that might help us debug this: Chain exists of: &pgdat->kswapd_wait --> &base->lock --> &(&zone->lock)->rlock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&zone->lock)->rlock); lock(&base->lock); lock(&(&zone->lock)->rlock); lock(&pgdat->kswapd_wait); *** DEADLOCK *** 2 locks held by syz-executor0/18110: #0: 00000000aef237e1 (&mm->mmap_sem){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1416 [inline] #0: 00000000aef237e1 (&mm->mmap_sem){++++}, at: __do_page_fault+0x339/0xd60 arch/x86/mm/fault.c:1541 #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:329 [inline] #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_bulk mm/page_alloc.c:2665 [inline] #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: __rmqueue_pcplist mm/page_alloc.c:3138 [inline] #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_pcplist mm/page_alloc.c:3167 [inline] #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: rmqueue mm/page_alloc.c:3189 [inline] #1: 000000005e86d102 (&(&zone->lock)->rlock){-.-.}, at: get_page_from_freelist+0x1ab1/0x50f0 mm/page_alloc.c:3608 stack backtrace: CPU: 0 PID: 18110 Comm: syz-executor0 Not tainted 4.20.0-next-20190103 #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1db/0x2d0 lib/dump_stack.c:113 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1224 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2350 [inline] __lock_acquire+0x2fed/0x4a10 kernel/locking/lockdep.c:3338 lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 __wake_up_common_lock+0x19b/0x390 kernel/sched/wait.c:120 __wake_up+0xe/0x10 kernel/sched/wait.c:145 wakeup_kswapd+0x5ba/0x8f0 mm/vmscan.c:4001 steal_suitable_fallback+0x50d/0x7c0 mm/page_alloc.c:2334 __rmqueue_fallback mm/page_alloc.c:2619 [inline] __rmqueue mm/page_alloc.c:2645 [inline] rmqueue_bulk mm/page_alloc.c:2667 [inline] __rmqueue_pcplist mm/page_alloc.c:3138 [inline] rmqueue_pcplist mm/page_alloc.c:3167 [inline] rmqueue mm/page_alloc.c:3189 [inline] get_page_from_freelist+0x2f53/0x50f0 mm/page_alloc.c:3608 __alloc_pages_nodemask+0x4fd/0xdc0 mm/page_alloc.c:4646 alloc_pages_vma+0xdd/0x540 mm/mempolicy.c:2070 alloc_zeroed_user_highpage_movable include/linux/highmem.h:208 [inline] do_anonymous_page mm/memory.c:2934 [inline] handle_pte_fault mm/memory.c:3779 [inline] __handle_mm_fault+0x2537/0x55a0 mm/memory.c:3905 handle_mm_fault+0x4ec/0xc80 mm/memory.c:3942 do_user_addr_fault arch/x86/mm/fault.c:1475 [inline] __do_page_fault+0x5da/0xd60 arch/x86/mm/fault.c:1541 do_page_fault+0xe6/0x7d8 arch/x86/mm/fault.c:1572 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1143 RIP: 0033:0x40f8ef Code: 0f 84 c8 02 00 00 48 83 bd 78 ff ff ff 00 0f 84 f9 04 00 00 48 8b 95 68 ff ff ff 44 89 95 38 ff ff ff 4c 8d ac 10 00 f7 ff ff <49> 89 85 90 06 00 00 49 8d 85 10 03 00 00 49 89 95 98 06 00 00 41 RSP: 002b:00007ffe89d4d370 EFLAGS: 00010206 RAX: 00007f8bda822000 RBX: 0000000000020000 RCX: 0000000000457f1a RDX: 0000000000021000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 00007ffe89d4d450 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe89d4d530 R13: 00007f8bda842700 R14: 000000000073bfac R15: 000000000073bfac