====================================================== WARNING: possible circular locking dependency detected 5.0.0-rc1+ #20 Not tainted ------------------------------------------------------ syz-executor3/29307 is trying to acquire lock: 00000000b145ce55 (cpu_hotplug_lock.rw_sem){++++}, at: __static_key_slow_dec kernel/jump_label.c:237 [inline] 00000000b145ce55 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:252 but task is already holding lock: 000000000cb38174 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x1ad/0x2b0 mm/util.c:348 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_sem){++++}: __might_fault mm/memory.c:4382 [inline] __might_fault+0x15e/0x1e0 mm/memory.c:4367 _copy_to_user+0x30/0x120 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:152 [inline] filldir64+0x279/0x470 fs/readdir.c:281 dir_emit_dot include/linux/fs.h:3474 [inline] dir_emit_dots include/linux/fs.h:3485 [inline] dcache_readdir+0x13a/0x640 fs/libfs.c:192 iterate_dir+0x489/0x5f0 fs/readdir.c:51 ksys_getdents64+0x245/0x4a0 fs/readdir.c:314 __do_sys_getdents64 fs/readdir.c:333 [inline] __se_sys_getdents64 fs/readdir.c:330 [inline] __x64_sys_getdents64+0x73/0xb0 fs/readdir.c:330 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&sb->s_type->i_mutex_key#4){++++}: down_write+0x8a/0x130 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:757 [inline] start_creating fs/debugfs/inode.c:307 [inline] start_creating+0xa9/0x1e0 fs/debugfs/inode.c:284 __debugfs_create_file+0x65/0x400 fs/debugfs/inode.c:347 debugfs_create_file+0x5a/0x70 fs/debugfs/inode.c:399 blk_create_buf_file_callback+0x33/0x40 kernel/trace/blktrace.c:444 relay_create_buf_file+0xf3/0x150 kernel/relay.c:428 relay_open_buf.part.0+0x74f/0xb40 kernel/relay.c:455 relay_open_buf kernel/relay.c:447 [inline] relay_open kernel/relay.c:597 [inline] relay_open+0x5f3/0xaf0 kernel/relay.c:561 do_blk_trace_setup+0x50d/0xdb0 kernel/trace/blktrace.c:532 __blk_trace_setup+0xe3/0x190 kernel/trace/blktrace.c:577 blk_trace_ioctl+0x170/0x300 kernel/trace/blktrace.c:716 blkdev_ioctl+0x141/0x2120 block/ioctl.c:591 block_ioctl+0xee/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (relay_channels_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 relay_prepare_cpu+0x2a/0x280 kernel/relay.c:525 cpuhp_invoke_callback+0x2f6/0x2110 kernel/cpu.c:168 cpuhp_up_callbacks kernel/cpu.c:591 [inline] _cpu_up+0x270/0x540 kernel/cpu.c:1147 do_cpu_up+0x1ba/0x200 kernel/cpu.c:1182 cpu_up+0x1b/0x20 kernel/cpu.c:1190 smp_init+0x1ad/0x1cc kernel/smp.c:578 kernel_init_freeable+0x33f/0x5ca init/main.c:1130 kernel_init+0x12/0x1c5 init/main.c:1055 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -> #0 (cpu_hotplug_lock.rw_sem){++++}: lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] cpus_read_lock+0x3e/0xe0 kernel/cpu.c:288 __static_key_slow_dec kernel/jump_label.c:237 [inline] static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:252 sw_perf_event_destroy+0x8b/0x140 kernel/events/core.c:8172 _free_event+0x3ee/0x15d0 kernel/events/core.c:4446 put_event+0x47/0x60 kernel/events/core.c:4532 perf_mmap_close+0x937/0x1210 kernel/events/core.c:5515 remove_vma+0xb5/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2585 [inline] __do_munmap+0x72e/0xef0 mm/mmap.c:2828 do_munmap mm/mmap.c:2836 [inline] mmap_region+0x698/0x1ca0 mm/mmap.c:1729 do_mmap+0xa09/0x1220 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2379 [inline] vm_mmap_pgoff+0x20b/0x2b0 mm/util.c:350 ksys_mmap_pgoff+0x4f8/0x650 mm/mmap.c:1609 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline] __x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91 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: cpu_hotplug_lock.rw_sem --> &sb->s_type->i_mutex_key#4 --> &mm->mmap_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&sb->s_type->i_mutex_key#4); lock(&mm->mmap_sem); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** 1 lock held by syz-executor3/29307: #0: 000000000cb38174 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x1ad/0x2b0 mm/util.c:348 stack backtrace: CPU: 1 PID: 29307 Comm: syz-executor3 Not tainted 5.0.0-rc1+ #20 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+0x3014/0x4a30 kernel/locking/lockdep.c:3338 lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] cpus_read_lock+0x3e/0xe0 kernel/cpu.c:288 __static_key_slow_dec kernel/jump_label.c:237 [inline] static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:252 sw_perf_event_destroy+0x8b/0x140 kernel/events/core.c:8172 _free_event+0x3ee/0x15d0 kernel/events/core.c:4446 put_event+0x47/0x60 kernel/events/core.c:4532 perf_mmap_close+0x937/0x1210 kernel/events/core.c:5515 remove_vma+0xb5/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2585 [inline] __do_munmap+0x72e/0xef0 mm/mmap.c:2828 do_munmap mm/mmap.c:2836 [inline] mmap_region+0x698/0x1ca0 mm/mmap.c:1729 do_mmap+0xa09/0x1220 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2379 [inline] vm_mmap_pgoff+0x20b/0x2b0 mm/util.c:350 ksys_mmap_pgoff+0x4f8/0x650 mm/mmap.c:1609 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline] __x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f4a037b3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 RBP: 000000000073bf00 R08: 0000000000000008 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007f4a037b46d4 R13: 00000000004c3b56 R14: 00000000004d6910 R15: 00000000ffffffff kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop4' (000000005aa63726): kobject_uevent_env kobject: 'loop4' (000000005aa63726): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' 8021q: adding VLAN 0 to HW filter on device bond0 kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0' 8021q: adding VLAN 0 to HW filter on device bond0 kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'kvm' (00000000837a977c): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop1' (0000000083026eca): kobject_uevent_env kobject: 'loop1' (0000000083026eca): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'kvm' (00000000837a977c): kobject_uevent_env kobject: 'loop0' (00000000457a3572): kobject_uevent_env kobject: 'loop0' (00000000457a3572): fill_kobj_path: path = '/devices/virtual/block/loop0'