====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc1-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/16761 is trying to acquire lock: ffffffff8c7d6aa0 (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 prepare_creds+0x3d/0x640 kernel/cred.c:262 prepare_exec_creds+0x14/0x260 kernel/cred.c:313 prepare_bprm_creds fs/exec.c:1467 [inline] bprm_execve+0xf9/0x1470 fs/exec.c:1799 do_execveat_common+0x44c/0x590 fs/exec.c:1920 do_execve fs/exec.c:1988 [inline] __do_sys_execve fs/exec.c:2064 [inline] __se_sys_execve fs/exec.c:2059 [inline] __x64_sys_execve+0x8e/0xa0 fs/exec.c:2059 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #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 alloc_thread_stack_node kernel/fork.c:245 [inline] dup_task_struct+0x65a/0x980 kernel/fork.c:875 copy_process+0x615/0x5b00 kernel/fork.c:1952 create_io_thread+0x14a/0x1c0 kernel/fork.c:2457 create_io_worker+0x200/0x7e0 fs/io-wq.c:633 create_worker_cb+0x7d/0xb0 fs/io-wq.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:212 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x180/0x220 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 *** 1 lock held by syz-executor.5/16761: #0: ffff8880b9d4d0c8 (lock#2){-.-.}-{2:2}, at: local_lock_acquire+0x7/0x130 include/linux/local_lock_internal.h:41 stack backtrace: CPU: 1 PID: 16761 Comm: syz-executor.5 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 alloc_thread_stack_node kernel/fork.c:245 [inline] dup_task_struct+0x65a/0x980 kernel/fork.c:875 copy_process+0x615/0x5b00 kernel/fork.c:1952 create_io_thread+0x14a/0x1c0 kernel/fork.c:2457 create_io_worker+0x200/0x7e0 fs/io-wq.c:633 create_worker_cb+0x7d/0xb0 fs/io-wq.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:212 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x180/0x220 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: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3a10867188 EFLAGS: 00000246 ORIG_RAX: 0000000000000007 RAX: fffffffffffffdfc RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000101 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffe5fef14cf R14: 00007f3a10867300 R15: 0000000000022000 BUG: sleeping function called from invalid context at mm/page_alloc.c:5167 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 16761, name: syz-executor.5 INFO: lockdep is turned off. irq event stamp: 5150 hardirqs last enabled at (5149): [] asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 hardirqs last disabled at (5150): [] __alloc_pages_bulk+0x801/0x1090 mm/page_alloc.c:5279 softirqs last enabled at (5060): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last enabled at (5060): [] __irq_exit_rcu+0x21b/0x260 kernel/softirq.c:636 softirqs last disabled at (4989): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (4989): [] __irq_exit_rcu+0x21b/0x260 kernel/softirq.c:636 CPU: 1 PID: 16761 Comm: syz-executor.5 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 alloc_thread_stack_node kernel/fork.c:245 [inline] dup_task_struct+0x65a/0x980 kernel/fork.c:875 copy_process+0x615/0x5b00 kernel/fork.c:1952 create_io_thread+0x14a/0x1c0 kernel/fork.c:2457 create_io_worker+0x200/0x7e0 fs/io-wq.c:633 create_worker_cb+0x7d/0xb0 fs/io-wq.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:212 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x180/0x220 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: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3a10867188 EFLAGS: 00000246 ORIG_RAX: 0000000000000007 RAX: fffffffffffffdfc RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000101 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffe5fef14cf R14: 00007f3a10867300 R15: 0000000000022000