====================================================== WARNING: possible circular locking dependency detected 4.20.0-next-20190103 #5 Not tainted ------------------------------------------------------ syz-executor0/7485 is trying to acquire lock: 0000000092b4b508 (&pgdat->kswapd_wait){....}, at: __wake_up_common_lock+0x19b/0x390 kernel/sched/wait.c:120 but task is already holding lock: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:329 [inline] 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_bulk mm/page_alloc.c:2665 [inline] 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: __rmqueue_pcplist mm/page_alloc.c:3138 [inline] 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_pcplist mm/page_alloc.c:3167 [inline] 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue mm/page_alloc.c:3189 [inline] 00000000da371bf7 (&(&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 kmem_cache_alloc+0x12d/0x710 mm/slab.c:3541 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] kmem_getpages mm/slab.c:1396 [inline] cache_grow_begin+0x9c/0x8c0 mm/slab.c:2664 fallback_alloc+0x1fd/0x2d0 mm/slab.c:3206 ____cache_alloc_node+0x1be/0x1e0 mm/slab.c:3274 slab_alloc_node mm/slab.c:3314 [inline] kmem_cache_alloc_node_trace+0xec/0x720 mm/slab.c:3648 __do_kmalloc_node mm/slab.c:3670 [inline] __kmalloc_node+0x3d/0x70 mm/slab.c:3678 kmalloc_node include/linux/slab.h:588 [inline] kvmalloc_node+0xbd/0x100 mm/util.c:416 kvmalloc include/linux/mm.h:639 [inline] btf_parse kernel/bpf/btf.c:2836 [inline] btf_new_fd+0x487/0x3660 kernel/bpf/btf.c:2908 bpf_btf_load kernel/bpf/syscall.c:2438 [inline] __do_sys_bpf+0x1c42/0x43c0 kernel/bpf/syscall.c:2659 __se_sys_bpf kernel/bpf/syscall.c:2580 [inline] __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:2580 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_current+0x107/0x210 mm/mempolicy.c:2106 alloc_pages include/linux/gfp.h:509 [inline] pte_alloc_one+0x1b/0x1a0 arch/x86/mm/pgtable.c:35 __pte_alloc+0x20/0x310 mm/memory.c:406 copy_pte_range mm/memory.c:830 [inline] copy_pmd_range mm/memory.c:906 [inline] copy_pud_range mm/memory.c:940 [inline] copy_p4d_range mm/memory.c:962 [inline] copy_page_range+0x1844/0x2730 mm/memory.c:1024 dup_mmap kernel/fork.c:584 [inline] dup_mm kernel/fork.c:1318 [inline] copy_mm kernel/fork.c:1373 [inline] copy_process+0x4291/0x8720 kernel/fork.c:1917 _do_fork+0x1a9/0x1170 kernel/fork.c:2216 __do_sys_clone kernel/fork.c:2323 [inline] __se_sys_clone kernel/fork.c:2317 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2317 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe 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 *** 4 locks held by syz-executor0/7485: #0: 00000000febf67c4 (&dup_mmap_sem){++++}, at: dup_mmap kernel/fork.c:470 [inline] #0: 00000000febf67c4 (&dup_mmap_sem){++++}, at: dup_mm kernel/fork.c:1318 [inline] #0: 00000000febf67c4 (&dup_mmap_sem){++++}, at: copy_mm kernel/fork.c:1373 [inline] #0: 00000000febf67c4 (&dup_mmap_sem){++++}, at: copy_process+0x30a2/0x8720 kernel/fork.c:1917 #1: 00000000b1e39ab4 (&mm->mmap_sem){++++}, at: dup_mmap kernel/fork.c:471 [inline] #1: 00000000b1e39ab4 (&mm->mmap_sem){++++}, at: dup_mm kernel/fork.c:1318 [inline] #1: 00000000b1e39ab4 (&mm->mmap_sem){++++}, at: copy_mm kernel/fork.c:1373 [inline] #1: 00000000b1e39ab4 (&mm->mmap_sem){++++}, at: copy_process+0x30be/0x8720 kernel/fork.c:1917 #2: 000000003dd56d2e (&mm->mmap_sem/1){+.+.}, at: dup_mmap kernel/fork.c:480 [inline] #2: 000000003dd56d2e (&mm->mmap_sem/1){+.+.}, at: dup_mm kernel/fork.c:1318 [inline] #2: 000000003dd56d2e (&mm->mmap_sem/1){+.+.}, at: copy_mm kernel/fork.c:1373 [inline] #2: 000000003dd56d2e (&mm->mmap_sem/1){+.+.}, at: copy_process+0x3116/0x8720 kernel/fork.c:1917 #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:329 [inline] #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_bulk mm/page_alloc.c:2665 [inline] #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: __rmqueue_pcplist mm/page_alloc.c:3138 [inline] #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue_pcplist mm/page_alloc.c:3167 [inline] #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: rmqueue mm/page_alloc.c:3189 [inline] #3: 00000000da371bf7 (&(&zone->lock)->rlock){-.-.}, at: get_page_from_freelist+0x1ab1/0x50f0 mm/page_alloc.c:3608 stack backtrace: CPU: 1 PID: 7485 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_current+0x107/0x210 mm/mempolicy.c:2106 alloc_pages include/linux/gfp.h:509 [inline] pte_alloc_one+0x1b/0x1a0 arch/x86/mm/pgtable.c:35 __pte_alloc+0x20/0x310 mm/memory.c:406 copy_pte_range mm/memory.c:830 [inline] copy_pmd_range mm/memory.c:906 [inline] copy_pud_range mm/memory.c:940 [inline] copy_p4d_range mm/memory.c:962 [inline] copy_page_range+0x1844/0x2730 mm/memory.c:1024 dup_mmap kernel/fork.c:584 [inline] dup_mm kernel/fork.c:1318 [inline] copy_mm kernel/fork.c:1373 [inline] copy_process+0x4291/0x8720 kernel/fork.c:1917 _do_fork+0x1a9/0x1170 kernel/fork.c:2216 __do_sys_clone kernel/fork.c:2323 [inline] __se_sys_clone kernel/fork.c:2317 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2317 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45649a Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00 RSP: 002b:00007ffc97ce0f00 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffc97ce0f00 RCX: 000000000045649a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffc97ce0f40 R08: 0000000000000001 R09: 000000000189f940 R10: 000000000189fc10 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000