====================================================== WARNING: possible circular locking dependency detected 6.4.0-rc3-syzkaller-00278-g49572d536129 #0 Not tainted ------------------------------------------------------ kswapd0/112 is trying to acquire lock: ffff88803fffeba0 (&pgdat->kswapd_wait){..-.}-{2:2}, at: __wake_up_common_lock+0xb8/0x140 kernel/sched/wait.c:137 but task is already holding lock: ffff88802c82b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline] ffff88802c82b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x23e/0xbe0 kernel/time/hrtimer.c:1749 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (hrtimer_bases.lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 lock_hrtimer_base kernel/time/hrtimer.c:173 [inline] hrtimer_start_range_ns+0xe9/0xd80 kernel/time/hrtimer.c:1296 hrtimer_start_expires include/linux/hrtimer.h:432 [inline] do_start_rt_bandwidth kernel/sched/rt.c:116 [inline] start_rt_bandwidth kernel/sched/rt.c:127 [inline] inc_rt_group kernel/sched/rt.c:1241 [inline] inc_rt_tasks kernel/sched/rt.c:1285 [inline] __enqueue_rt_entity kernel/sched/rt.c:1461 [inline] enqueue_rt_entity kernel/sched/rt.c:1510 [inline] enqueue_task_rt+0xa86/0xfc0 kernel/sched/rt.c:1545 enqueue_task+0xad/0x330 kernel/sched/core.c:2082 __sched_setscheduler.constprop.0+0xb89/0x25d0 kernel/sched/core.c:7774 _sched_setscheduler kernel/sched/core.c:7820 [inline] sched_setscheduler_nocheck kernel/sched/core.c:7867 [inline] sched_set_fifo+0xb1/0x110 kernel/sched/core.c:7891 irq_thread+0xe3/0x540 kernel/irq/manage.c:1302 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #3 (&rt_b->rt_runtime_lock){-.-.}-{2:2}: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 __enable_runtime kernel/sched/rt.c:876 [inline] rq_online_rt+0xb3/0x3b0 kernel/sched/rt.c:2485 set_rq_online.part.0+0xf9/0x140 kernel/sched/core.c:9541 set_rq_online kernel/sched/core.c:9533 [inline] sched_cpu_activate+0x216/0x440 kernel/sched/core.c:9649 cpuhp_invoke_callback+0x645/0xeb0 kernel/cpu.c:192 cpuhp_thread_fun+0x47f/0x700 kernel/cpu.c:815 smpboot_thread_fn+0x659/0x9e0 kernel/smpboot.c:164 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x34/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:558 raw_spin_rq_lock kernel/sched/sched.h:1366 [inline] rq_lock kernel/sched/sched.h:1653 [inline] task_fork_fair+0x74/0x4f0 kernel/sched/fair.c:12095 sched_cgroup_fork+0x3d1/0x540 kernel/sched/core.c:4777 copy_process+0x4b8a/0x7600 kernel/fork.c:2618 kernel_clone+0xeb/0x890 kernel/fork.c:2918 user_mode_thread+0xb1/0xf0 kernel/fork.c:2996 rest_init+0x27/0x2b0 init/main.c:700 arch_call_rest_init+0x13/0x30 init/main.c:834 start_kernel+0x3b6/0x490 init/main.c:1088 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb3/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0xf4/0xfb -> #1 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 try_to_wake_up+0xab/0x1c40 kernel/sched/core.c:4191 autoremove_wake_function+0x16/0x150 kernel/sched/wait.c:419 __wake_up_common+0x147/0x650 kernel/sched/wait.c:107 __wake_up_common_lock+0xd4/0x140 kernel/sched/wait.c:138 wakeup_kswapd+0x3fe/0x5c0 mm/vmscan.c:7798 rmqueue mm/page_alloc.c:3057 [inline] get_page_from_freelist+0x6c5/0x2c00 mm/page_alloc.c:3499 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] __page_frag_cache_refill mm/page_alloc.c:4894 [inline] page_frag_alloc_align+0x27d/0xa60 mm/page_alloc.c:4925 __netdev_alloc_frag_align+0x123/0x190 net/core/skbuff.c:325 netdev_alloc_frag include/linux/skbuff.h:3175 [inline] e1000_alloc_frag drivers/net/ethernet/intel/e1000/e1000_main.c:2072 [inline] e1000_alloc_rx_buffers+0x26d/0xd60 drivers/net/ethernet/intel/e1000/e1000_main.c:4580 e1000_clean_rx_irq+0xa2a/0x1010 drivers/net/ethernet/intel/e1000/e1000_main.c:4468 e1000_clean+0x9bf/0x26b0 drivers/net/ethernet/intel/e1000/e1000_main.c:3803 __napi_poll+0xb7/0x6f0 net/core/dev.c:6496 napi_poll net/core/dev.c:6563 [inline] net_rx_action+0x8a9/0xcb0 net/core/dev.c:6696 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 common_interrupt+0xad/0xd0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] default_idle+0xf/0x20 arch/x86/kernel/process.c:710 default_idle_call+0x67/0xa0 kernel/sched/idle.c:97 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x317/0x3c0 kernel/sched/idle.c:282 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 start_secondary+0x221/0x2b0 arch/x86/kernel/smpboot.c:269 secondary_startup_64_no_verify+0xf4/0xfb -> #0 (&pgdat->kswapd_wait){..-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3108 [inline] check_prevs_add kernel/locking/lockdep.c:3227 [inline] validate_chain kernel/locking/lockdep.c:3842 [inline] __lock_acquire+0x2f21/0x5df0 kernel/locking/lockdep.c:5074 lock_acquire kernel/locking/lockdep.c:5691 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5656 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 __wake_up_common_lock+0xb8/0x140 kernel/sched/wait.c:137 wakeup_kswapd+0x3fe/0x5c0 mm/vmscan.c:7798 wake_all_kswapds+0x182/0x2d0 mm/page_alloc.c:4028 __alloc_pages_slowpath.constprop.0+0x1724/0x2170 mm/page_alloc.c:4296 __alloc_pages+0x408/0x4a0 mm/page_alloc.c:4781 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3192 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3291 __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] slab_alloc mm/slub.c:3459 [inline] __kmem_cache_alloc_lru mm/slub.c:3466 [inline] kmem_cache_alloc+0x38e/0x3b0 mm/slub.c:3475 kmem_cache_zalloc include/linux/slab.h:670 [inline] fill_pool+0x264/0x5c0 lib/debugobjects.c:168 debug_objects_fill_pool lib/debugobjects.c:597 [inline] debug_object_activate+0xfd/0x400 lib/debugobjects.c:693 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x320 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xa5b/0xbe0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x3c/0x70 kernel/locking/spinlock.c:194 kswapd_try_to_sleep mm/vmscan.c:7582 [inline] kswapd+0x33e/0xd60 mm/vmscan.c:7707 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 other info that might help us debug this: Chain exists of: &pgdat->kswapd_wait --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(hrtimer_bases.lock); lock(&rt_b->rt_runtime_lock); lock(hrtimer_bases.lock); lock(&pgdat->kswapd_wait); *** DEADLOCK *** 1 lock held by kswapd0/112: #0: ffff88802c82b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline] #0: ffff88802c82b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x23e/0xbe0 kernel/time/hrtimer.c:1749 stack backtrace: CPU: 2 PID: 112 Comm: kswapd0 Not tainted 6.4.0-rc3-syzkaller-00278-g49572d536129 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2188 check_prev_add kernel/locking/lockdep.c:3108 [inline] check_prevs_add kernel/locking/lockdep.c:3227 [inline] validate_chain kernel/locking/lockdep.c:3842 [inline] __lock_acquire+0x2f21/0x5df0 kernel/locking/lockdep.c:5074 lock_acquire kernel/locking/lockdep.c:5691 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5656 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 __wake_up_common_lock+0xb8/0x140 kernel/sched/wait.c:137 wakeup_kswapd+0x3fe/0x5c0 mm/vmscan.c:7798 wake_all_kswapds+0x182/0x2d0 mm/page_alloc.c:4028 __alloc_pages_slowpath.constprop.0+0x1724/0x2170 mm/page_alloc.c:4296 __alloc_pages+0x408/0x4a0 mm/page_alloc.c:4781 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3192 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3291 __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] slab_alloc mm/slub.c:3459 [inline] __kmem_cache_alloc_lru mm/slub.c:3466 [inline] kmem_cache_alloc+0x38e/0x3b0 mm/slub.c:3475 kmem_cache_zalloc include/linux/slab.h:670 [inline] fill_pool+0x264/0x5c0 lib/debugobjects.c:168 debug_objects_fill_pool lib/debugobjects.c:597 [inline] debug_object_activate+0xfd/0x400 lib/debugobjects.c:693 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x320 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xa5b/0xbe0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x3c/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 e6 9b 52 f7 48 89 ef e8 0e 0a 53 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 cf e0 44 f7 65 8b 05 f0 72 f0 75 85 c0 74 0a 5b 5d c3 e8 5c 9a RSP: 0018:ffffc90000e5fdd0 EFLAGS: 00000206 RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff1cf4941 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff88803fffeb88 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1cf4f4a R11: 0000000000000000 R12: 0000000000000000 R13: ffff888016990000 R14: 0000000000000002 R15: ffff88803fffa000 kswapd_try_to_sleep mm/vmscan.c:7582 [inline] kswapd+0x33e/0xd60 mm/vmscan.c:7707 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 ---------------- Code disassembly (best guess): 0: 74 24 je 0x26 2: 10 e8 adc %ch,%al 4: e6 9b out %al,$0x9b 6: 52 push %rdx 7: f7 48 89 ef e8 0e 0a testl $0xa0ee8ef,-0x77(%rax) e: 53 push %rbx f: f7 81 e3 00 02 00 00 testl $0x9c257500,0x200e3(%rcx) 16: 75 25 9c 19: 58 pop %rax 1a: f6 c4 02 test $0x2,%ah 1d: 75 2d jne 0x4c 1f: 48 85 db test %rbx,%rbx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 cf e0 44 f7 callq 0xf744e0fe <-- trapping instruction 2f: 65 8b 05 f0 72 f0 75 mov %gs:0x75f072f0(%rip),%eax # 0x75f07326 36: 85 c0 test %eax,%eax 38: 74 0a je 0x44 3a: 5b pop %rbx 3b: 5d pop %rbp 3c: c3 retq 3d: e8 .byte 0xe8 3e: 5c pop %rsp 3f: 9a (bad)