======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc2-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.0/7348 is trying to acquire lock:
ffff88807ffdaba0 (&pgdat->kswapd_wait){-.-.}-{2:2}, at: __wake_up_common_lock+0xb8/0x140 kernel/sched/wait.c:137

but task is already holding lock:
ffff88802c92b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
ffff88802c92b858 (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:7797
       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
       __folio_alloc+0x16/0x40 mm/page_alloc.c:4800
       vma_alloc_folio+0x155/0x890 mm/mempolicy.c:2240
       do_anonymous_page mm/memory.c:4085 [inline]
       do_pte_missing mm/memory.c:3645 [inline]
       handle_pte_fault mm/memory.c:4947 [inline]
       __handle_mm_fault+0x224c/0x41c0 mm/memory.c:5089
       handle_mm_fault+0x2af/0x9f0 mm/memory.c:5243
       do_user_addr_fault+0x2ca/0x1210 arch/x86/mm/fault.c:1349
       handle_page_fault arch/x86/mm/fault.c:1534 [inline]
       exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

-> #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:7797
       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_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1811
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
       __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1112
       sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1106
       asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
       __sanitizer_cov_trace_pc+0x50/0x70 kernel/kcov.c:212
       __get_compat_msghdr+0x2cf/0x4b0 net/compat.c:78
       get_compat_msghdr+0xb2/0x150 net/compat.c:94
       recvmsg_copy_msghdr net/socket.c:2686 [inline]
       ___sys_recvmsg+0x172/0x180 net/socket.c:2760
       do_recvmmsg+0x55d/0x6f0 net/socket.c:2850
       __sys_recvmmsg+0x242/0x250 net/socket.c:2937
       __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
       __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
       __ia32_compat_sys_recvmmsg_time32+0xc6/0x160 net/compat.c:414
       do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
       __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
       do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x70/0x82

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 syz-executor.0/7348:
 #0: ffff88802c92b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 #0: ffff88802c92b858 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x23e/0xbe0 kernel/time/hrtimer.c:1749

stack backtrace:
CPU: 3 PID: 7348 Comm: syz-executor.0 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <IRQ>
 __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:7797
 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_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__sanitizer_cov_trace_pc+0x50/0x70 kernel/kcov.c:212
Code: 0e 85 c9 74 35 8b 82 0c 16 00 00 85 c0 74 2b 8b 82 e8 15 00 00 83 f8 02 75 20 48 8b 8a f0 15 00 00 8b 92 ec 15 00 00 48 8b 01 <48> 83 c0 01 48 39 c2 76 07 48 89 01 48 89 34 c1 c3 66 66 2e 0f 1f
RSP: 0018:ffffc9000f5e7a28 EFLAGS: 00000246
RAX: 000000000003ffff RBX: ffffc9000f5e7d60 RCX: ffffc9000ca06000
RDX: 0000000000040000 RSI: ffffffff8826795f RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000400
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc9000f5e7b60
R13: 0000000000000000 R14: 0000000000000000 R15: ffffc9000f5e7b40
 __get_compat_msghdr+0x2cf/0x4b0 net/compat.c:78
 get_compat_msghdr+0xb2/0x150 net/compat.c:94
 recvmsg_copy_msghdr net/socket.c:2686 [inline]
 ___sys_recvmsg+0x172/0x180 net/socket.c:2760
 do_recvmmsg+0x55d/0x6f0 net/socket.c:2850
 __sys_recvmmsg+0x242/0x250 net/socket.c:2937
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xc6/0x160 net/compat.c:414
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f71579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f4b5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	85 c9                	test   %ecx,%ecx
   2:	74 35                	je     0x39
   4:	8b 82 0c 16 00 00    	mov    0x160c(%rdx),%eax
   a:	85 c0                	test   %eax,%eax
   c:	74 2b                	je     0x39
   e:	8b 82 e8 15 00 00    	mov    0x15e8(%rdx),%eax
  14:	83 f8 02             	cmp    $0x2,%eax
  17:	75 20                	jne    0x39
  19:	48 8b 8a f0 15 00 00 	mov    0x15f0(%rdx),%rcx
  20:	8b 92 ec 15 00 00    	mov    0x15ec(%rdx),%edx
  26:	48 8b 01             	mov    (%rcx),%rax
* 29:	48 83 c0 01          	add    $0x1,%rax <-- trapping instruction
  2d:	48 39 c2             	cmp    %rax,%rdx
  30:	76 07                	jbe    0x39
  32:	48 89 01             	mov    %rax,(%rcx)
  35:	48 89 34 c1          	mov    %rsi,(%rcx,%rax,8)
  39:	c3                   	retq
  3a:	66                   	data16
  3b:	66                   	data16
  3c:	2e                   	cs
  3d:	0f                   	.byte 0xf
  3e:	1f                   	(bad)