====================================================== WARNING: possible circular locking dependency detected 5.0.0-rc4-next-20190201 #25 Not tainted ------------------------------------------------------ syz-executor5/26681 is trying to acquire lock: 000000000877ef07 (cpu_hotplug_lock.rw_sem){++++}, at: __static_key_slow_dec kernel/jump_label.c:237 [inline] 000000000877ef07 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:252 but task is already holding lock: 0000000006734507 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x173/0x230 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:4398 [inline] __might_fault+0x15e/0x1e0 mm/memory.c:4383 perf_copy_attr+0xae/0x810 kernel/events/core.c:10369 _perf_ioctl+0x579/0x1190 kernel/events/core.c:5090 perf_ioctl+0x5c/0x90 kernel/events/core.c:5117 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd6e/0x1390 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+0x103/0x610 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+0xf7/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 perf_event_init_cpu+0xcf/0x180 kernel/events/core.c:11902 perf_event_init+0x317/0x363 kernel/events/core.c:11949 start_kernel+0x4dd/0x854 init/main.c:660 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:470 x86_64_start_kernel+0x77/0x7b 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+0xf7/0x1310 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:11896 cpuhp_invoke_callback+0x20a/0x1bc0 kernel/cpu.c:168 cpuhp_up_callbacks kernel/cpu.c:600 [inline] _cpu_up+0x270/0x540 kernel/cpu.c:1156 do_cpu_up+0x1ba/0x200 kernel/cpu.c:1191 cpu_up+0x1b/0x20 kernel/cpu.c:1199 smp_init+0x1ad/0x1c9 kernel/smp.c:578 kernel_init_freeable+0x33c/0x5c4 init/main.c:1146 kernel_init+0x12/0x1c5 init/main.c:1071 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -> #0 (cpu_hotplug_lock.rw_sem){++++}: lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3826 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:8382 _free_event+0x356/0x13c0 kernel/events/core.c:4452 put_event+0x47/0x60 kernel/events/core.c:4538 perf_mmap_close+0x590/0xd20 kernel/events/core.c:5521 remove_vma+0xb5/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2584 [inline] __do_munmap+0x72e/0xef0 mm/mmap.c:2827 do_munmap mm/mmap.c:2835 [inline] mmap_region+0x227/0x1770 mm/mmap.c:1729 do_mmap+0x8e2/0x1080 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2377 [inline] vm_mmap_pgoff+0x1c5/0x230 mm/util.c:350 ksys_mmap_pgoff+0x4aa/0x630 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+0x103/0x610 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-executor5/26681: #0: 0000000006734507 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x173/0x230 mm/util.c:348 stack backtrace: CPU: 1 PID: 26681 Comm: syz-executor5 Not tainted 5.0.0-rc4-next-20190201 #25 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+0x172/0x1f0 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:1855 [inline] check_prevs_add kernel/locking/lockdep.c:1968 [inline] validate_chain kernel/locking/lockdep.c:2339 [inline] __lock_acquire+0x2e7a/0x4790 kernel/locking/lockdep.c:3320 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3826 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:8382 _free_event+0x356/0x13c0 kernel/events/core.c:4452 put_event+0x47/0x60 kernel/events/core.c:4538 perf_mmap_close+0x590/0xd20 kernel/events/core.c:5521 remove_vma+0xb5/0x180 mm/mmap.c:181 remove_vma_list mm/mmap.c:2584 [inline] __do_munmap+0x72e/0xef0 mm/mmap.c:2827 do_munmap mm/mmap.c:2835 [inline] mmap_region+0x227/0x1770 mm/mmap.c:1729 do_mmap+0x8e2/0x1080 mm/mmap.c:1559 do_mmap_pgoff include/linux/mm.h:2377 [inline] vm_mmap_pgoff+0x1c5/0x230 mm/util.c:350 ksys_mmap_pgoff+0x4aa/0x630 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+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457e39 Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fee2fbbbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457e39 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 RBP: 000000000073bfa0 R08: 000000000000000a R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007fee2fbbc6d4 R13: 00000000004c3b36 R14: 00000000004d6b90 R15: 00000000ffffffff