====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc1-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/9873 is trying to acquire lock: ffffffff8c7d6b20 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x30 mm/page_alloc.c:4210 but task is already holding lock: ffff8880b9d4d0c8 (lock#2){-.-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:41 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (lock#2){-.-.}-{2:2}: lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625 local_lock_acquire+0x23/0x130 include/linux/local_lock_internal.h:42 free_unref_page+0x242/0x550 mm/page_alloc.c:3427 mm_free_pgd kernel/fork.c:636 [inline] __mmdrop+0xae/0x3f0 kernel/fork.c:687 mmdrop include/linux/sched/mm.h:49 [inline] finish_task_switch+0x221/0x630 kernel/sched/core.c:4582 context_switch kernel/sched/core.c:4686 [inline] __schedule+0xc0f/0x11f0 kernel/sched/core.c:5940 preempt_schedule_irq+0xe3/0x190 kernel/sched/core.c:6328 irqentry_exit+0x56/0x90 kernel/entry/common.c:427 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 lock_acquire+0x1e7/0x4a0 kernel/locking/lockdep.c:5629 __fs_reclaim_acquire+0x20/0x30 mm/page_alloc.c:4552 fs_reclaim_acquire+0x59/0xf0 mm/page_alloc.c:4566 might_alloc include/linux/sched/mm.h:198 [inline] slab_pre_alloc_hook mm/slab.h:485 [inline] slab_alloc_node mm/slub.c:2902 [inline] slab_alloc mm/slub.c:2989 [inline] kmem_cache_alloc+0x3a/0x340 mm/slub.c:2994 ptlock_alloc+0x1c/0x60 mm/memory.c:5449 ptlock_init include/linux/mm.h:2223 [inline] pgtable_pte_page_ctor include/linux/mm.h:2250 [inline] __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline] pte_alloc_one+0xc3/0x320 arch/x86/mm/pgtable.c:33 do_fault_around mm/memory.c:4136 [inline] do_read_fault+0x2ed/0x650 mm/memory.c:4157 do_fault mm/memory.c:4291 [inline] handle_pte_fault mm/memory.c:4549 [inline] __handle_mm_fault mm/memory.c:4684 [inline] handle_mm_fault+0x17e5/0x2500 mm/memory.c:4782 do_user_addr_fault+0x8ce/0x10c0 arch/x86/mm/fault.c:1390 handle_page_fault arch/x86/mm/fault.c:1475 [inline] exc_page_fault+0xa1/0x1e0 arch/x86/mm/fault.c:1531 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3051 [inline] check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174 validate_chain kernel/locking/lockdep.c:3789 [inline] __lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015 lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625 __fs_reclaim_acquire+0x20/0x30 mm/page_alloc.c:4552 fs_reclaim_acquire+0x59/0xf0 mm/page_alloc.c:4566 prepare_alloc_pages+0x151/0x5a0 mm/page_alloc.c:5164 __alloc_pages+0x14d/0x5f0 mm/page_alloc.c:5363 stack_depot_save+0x361/0x490 lib/stackdepot.c:303 save_stack+0xf9/0x1f0 mm/page_owner.c:120 __set_page_owner+0x42/0x2f0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2433 [inline] __alloc_pages_bulk+0x9f2/0x1090 mm/page_alloc.c:5301 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline] vm_area_alloc_pages mm/vmalloc.c:2793 [inline] __vmalloc_area_node mm/vmalloc.c:2863 [inline] __vmalloc_node_range+0x3ad/0x7f0 mm/vmalloc.c:2966 __vmalloc_node mm/vmalloc.c:3015 [inline] __vmalloc+0x75/0x80 mm/vmalloc.c:3029 snd_dma_vmalloc_alloc+0x48/0x70 sound/core/memalloc.c:236 __snd_dma_alloc_pages sound/core/memalloc.c:38 [inline] snd_dma_alloc_pages+0x104/0x1d0 sound/core/memalloc.c:71 do_alloc_pages sound/core/pcm_memory.c:43 [inline] snd_pcm_lib_malloc_pages+0x323/0x720 sound/core/pcm_memory.c:383 snd_pcm_hw_params+0x46d/0x1740 sound/core/pcm_native.c:705 snd_pcm_oss_change_params_locked+0x245a/0x4390 sound/core/oss/pcm_oss.c:947 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1091 [inline] snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1150 [inline] snd_pcm_oss_sync+0x587/0xee0 sound/core/oss/pcm_oss.c:1650 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x201/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:302 do_syscall_64+0x4c/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock#2); lock(fs_reclaim); lock(lock#2); lock(fs_reclaim); *** DEADLOCK *** 2 locks held by syz-executor.1/9873: #0: ffff888029e84440 (&runtime->oss.params_lock){+.+.}-{3:3}, at: snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1088 [inline] #0: ffff888029e84440 (&runtime->oss.params_lock){+.+.}-{3:3}, at: snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1150 [inline] #0: ffff888029e84440 (&runtime->oss.params_lock){+.+.}-{3:3}, at: snd_pcm_oss_sync+0x34b/0xee0 sound/core/oss/pcm_oss.c:1650 #1: ffff8880b9d4d0c8 (lock#2){-.-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:41 stack backtrace: CPU: 1 PID: 9873 Comm: syz-executor.1 Not tainted 5.14.0-rc1-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+0x1ae/0x29f lib/dump_stack.c:105 print_circular_bug+0xb17/0xdc0 kernel/locking/lockdep.c:2009 check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2131 check_prev_add kernel/locking/lockdep.c:3051 [inline] check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174 validate_chain kernel/locking/lockdep.c:3789 [inline] __lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015 lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625 __fs_reclaim_acquire+0x20/0x30 mm/page_alloc.c:4552 fs_reclaim_acquire+0x59/0xf0 mm/page_alloc.c:4566 prepare_alloc_pages+0x151/0x5a0 mm/page_alloc.c:5164 __alloc_pages+0x14d/0x5f0 mm/page_alloc.c:5363 stack_depot_save+0x361/0x490 lib/stackdepot.c:303 save_stack+0xf9/0x1f0 mm/page_owner.c:120 __set_page_owner+0x42/0x2f0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2433 [inline] __alloc_pages_bulk+0x9f2/0x1090 mm/page_alloc.c:5301 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline] vm_area_alloc_pages mm/vmalloc.c:2793 [inline] __vmalloc_area_node mm/vmalloc.c:2863 [inline] __vmalloc_node_range+0x3ad/0x7f0 mm/vmalloc.c:2966 __vmalloc_node mm/vmalloc.c:3015 [inline] __vmalloc+0x75/0x80 mm/vmalloc.c:3029 snd_dma_vmalloc_alloc+0x48/0x70 sound/core/memalloc.c:236 __snd_dma_alloc_pages sound/core/memalloc.c:38 [inline] snd_dma_alloc_pages+0x104/0x1d0 sound/core/memalloc.c:71 do_alloc_pages sound/core/pcm_memory.c:43 [inline] snd_pcm_lib_malloc_pages+0x323/0x720 sound/core/pcm_memory.c:383 snd_pcm_hw_params+0x46d/0x1740 sound/core/pcm_native.c:705 snd_pcm_oss_change_params_locked+0x245a/0x4390 sound/core/oss/pcm_oss.c:947 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1091 [inline] snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1150 [inline] snd_pcm_oss_sync+0x587/0xee0 sound/core/oss/pcm_oss.c:1650 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x201/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:302 do_syscall_64+0x4c/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4193eb Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffc4d28cc10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004193eb RDX: 00000000005739b8 RSI: ffffffff81a64552 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b2c1232ac R10: 00000000000010df R11: 0000000000000293 R12: 0000000000011932 R13: 00000000000003e8 R14: 000000000056bf80 R15: 00000000000118b5 BUG: sleeping function called from invalid context at mm/page_alloc.c:5167 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 9873, name: syz-executor.1 INFO: lockdep is turned off. irq event stamp: 3744 hardirqs last enabled at (3743): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (3743): [] _raw_spin_unlock_irqrestore+0x8b/0x120 kernel/locking/spinlock.c:191 hardirqs last disabled at (3744): [] __alloc_pages_bulk+0x801/0x1090 mm/page_alloc.c:5279 softirqs last enabled at (3452): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last enabled at (3452): [] __irq_exit_rcu+0x21b/0x260 kernel/softirq.c:636 softirqs last disabled at (2847): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (2847): [] __irq_exit_rcu+0x21b/0x260 kernel/softirq.c:636 CPU: 1 PID: 9873 Comm: syz-executor.1 Not tainted 5.14.0-rc1-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+0x1ae/0x29f lib/dump_stack.c:105 ___might_sleep+0x4e5/0x6b0 kernel/sched/core.c:9154 prepare_alloc_pages+0x1c0/0x5a0 mm/page_alloc.c:5167 __alloc_pages+0x14d/0x5f0 mm/page_alloc.c:5363 stack_depot_save+0x361/0x490 lib/stackdepot.c:303 save_stack+0xf9/0x1f0 mm/page_owner.c:120 __set_page_owner+0x42/0x2f0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2433 [inline] __alloc_pages_bulk+0x9f2/0x1090 mm/page_alloc.c:5301 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline] vm_area_alloc_pages mm/vmalloc.c:2793 [inline] __vmalloc_area_node mm/vmalloc.c:2863 [inline] __vmalloc_node_range+0x3ad/0x7f0 mm/vmalloc.c:2966 __vmalloc_node mm/vmalloc.c:3015 [inline] __vmalloc+0x75/0x80 mm/vmalloc.c:3029 snd_dma_vmalloc_alloc+0x48/0x70 sound/core/memalloc.c:236 __snd_dma_alloc_pages sound/core/memalloc.c:38 [inline] snd_dma_alloc_pages+0x104/0x1d0 sound/core/memalloc.c:71 do_alloc_pages sound/core/pcm_memory.c:43 [inline] snd_pcm_lib_malloc_pages+0x323/0x720 sound/core/pcm_memory.c:383 snd_pcm_hw_params+0x46d/0x1740 sound/core/pcm_native.c:705 snd_pcm_oss_change_params_locked+0x245a/0x4390 sound/core/oss/pcm_oss.c:947 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1091 [inline] snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1150 [inline] snd_pcm_oss_sync+0x587/0xee0 sound/core/oss/pcm_oss.c:1650 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x201/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:302 do_syscall_64+0x4c/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4193eb Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffc4d28cc10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004193eb RDX: 00000000005739b8 RSI: ffffffff81a64552 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b2c1232ac R10: 00000000000010df R11: 0000000000000293 R12: 0000000000011932 R13: 00000000000003e8 R14: 000000000056bf80 R15: 00000000000118b5