====================================================== WARNING: possible circular locking dependency detected 4.19.0+ #318 Not tainted ------------------------------------------------------ syz-executor3/25522 is trying to acquire lock: 000000009aed6c7d (cpu_hotplug_lock.rw_sem){++++}, at: __static_key_slow_dec kernel/jump_label.c:239 [inline] 000000009aed6c7d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_dec+0x57/0xa0 kernel/jump_label.c:254 but task is already holding lock: 00000000d2ffe4a1 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x1b5/0x2c0 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+0x15e/0x1e0 mm/memory.c:4360 _copy_to_user+0x30/0x110 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] perf_read_group kernel/events/core.c:4776 [inline] __perf_read kernel/events/core.c:4843 [inline] perf_read+0x7e3/0xa60 kernel/events/core.c:4858 __vfs_read+0x117/0x9b0 fs/read_write.c:416 vfs_read+0x17f/0x3c0 fs/read_write.c:452 ksys_read+0x101/0x260 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&cpuctx_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x166/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 perf_event_init_cpu+0xd2/0x180 kernel/events/core.c:11679 perf_event_init+0x519/0x595 kernel/events/core.c:11726 start_kernel+0x646/0xa2b init/main.c:652 x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:472 x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #1 (pmus_lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x166/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 perf_event_init_cpu+0x2f/0x180 kernel/events/core.c:11673 cpuhp_invoke_callback+0x35d/0x2100 kernel/cpu.c:167 cpuhp_up_callbacks kernel/cpu.c:584 [inline] _cpu_up+0x290/0x560 kernel/cpu.c:1139 do_cpu_up+0x1ca/0x210 kernel/cpu.c:1173 cpu_up+0x18/0x20 kernel/cpu.c:1181 smp_init+0x1a3/0x1be kernel/smp.c:578 kernel_init_freeable+0x431/0x6b9 init/main.c:1146 kernel_init+0x11/0x1ae init/main.c:1071 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -> #0 (cpu_hotplug_lock.rw_sem){++++}: lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 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/0xd0 kernel/cpu.c:287 __static_key_slow_dec kernel/jump_label.c:239 [inline] static_key_slow_dec+0x57/0xa0 kernel/jump_label.c:254 sw_perf_event_destroy+0x8b/0x140 kernel/events/core.c:8172 _free_event+0x414/0x1660 kernel/events/core.c:4446 put_event+0x48/0x60 kernel/events/core.c:4532 perf_mmap_close+0x62f/0x1220 kernel/events/core.c:5515 remove_vma+0xb1/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2574 [inline] __do_munmap+0x751/0xf80 mm/mmap.c:2817 do_munmap mm/mmap.c:2825 [inline] mmap_region+0x6a7/0x1cd0 mm/mmap.c:1729 do_mmap+0xa22/0x1230 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2320 [inline] vm_mmap_pgoff+0x213/0x2c0 mm/util.c:350 ksys_mmap_pgoff+0x4da/0x660 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+0x1b9/0x820 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 --> &cpuctx_mutex --> &mm->mmap_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&cpuctx_mutex); lock(&mm->mmap_sem); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** 1 lock held by syz-executor3/25522: #0: 00000000d2ffe4a1 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x1b5/0x2c0 mm/util.c:348 stack backtrace: CPU: 1 PID: 25522 Comm: syz-executor3 Not tainted 4.19.0+ #318 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+0x244/0x39d lib/dump_stack.c:113 print_circular_bug.isra.35.cold.54+0x1bd/0x27d kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2347 [inline] __lock_acquire+0x3399/0x4c20 kernel/locking/lockdep.c:3341 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 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/0xd0 kernel/cpu.c:287 __static_key_slow_dec kernel/jump_label.c:239 [inline] static_key_slow_dec+0x57/0xa0 kernel/jump_label.c:254 sw_perf_event_destroy+0x8b/0x140 kernel/events/core.c:8172 _free_event+0x414/0x1660 kernel/events/core.c:4446 put_event+0x48/0x60 kernel/events/core.c:4532 perf_mmap_close+0x62f/0x1220 kernel/events/core.c:5515 remove_vma+0xb1/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2574 [inline] __do_munmap+0x751/0xf80 mm/mmap.c:2817 do_munmap mm/mmap.c:2825 [inline] mmap_region+0x6a7/0x1cd0 mm/mmap.c:1729 do_mmap+0xa22/0x1230 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2320 [inline] vm_mmap_pgoff+0x213/0x2c0 mm/util.c:350 ksys_mmap_pgoff+0x4da/0x660 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+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f217cd7fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 RBP: 000000000072bfa0 R08: 000000000000000a R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007f217cd806d4 R13: 00000000004c2a9d R14: 00000000004d40c0 R15: 00000000ffffffff kobject: 'loop2' (00000000ca2cc98a): kobject_uevent_env kobject: 'loop2' (00000000ca2cc98a): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop4' (00000000812c9751): kobject_uevent_env kobject: 'loop4' (00000000812c9751): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (00000000fba26143): kobject_uevent_env kobject: 'loop0' (00000000fba26143): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (0000000099278ded): kobject_uevent_env kobject: 'loop3' (0000000099278ded): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop1' (0000000032ae37eb): kobject_uevent_env kobject: 'loop1' (0000000032ae37eb): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (00000000fba26143): kobject_uevent_env kobject: 'loop0' (00000000fba26143): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (00000000fba26143): kobject_uevent_env kobject: 'loop0' (00000000fba26143): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop4' (00000000812c9751): kobject_uevent_env kobject: 'loop4' (00000000812c9751): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop2' (00000000ca2cc98a): kobject_uevent_env kobject: 'loop2' (00000000ca2cc98a): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop0' (00000000fba26143): kobject_uevent_env kobject: 'loop0' (00000000fba26143): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (0000000032ae37eb): kobject_uevent_env kobject: 'loop1' (0000000032ae37eb): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop3' (0000000099278ded): kobject_uevent_env kobject: 'loop3' (0000000099278ded): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop0' (00000000fba26143): kobject_uevent_env kobject: 'loop0' (00000000fba26143): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop5' (000000001bc15b41): kobject_uevent_env kobject: 'loop5' (000000001bc15b41): fill_kobj_path: path = '/devices/virtual/block/loop5'