====================================================== WARNING: possible circular locking dependency detected 5.13.0-rc1-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/26566 is trying to acquire lock: ffff88808aa32b58 (&mm->mmap_lock#2){++++}-{3:3}, at: __might_fault+0xa3/0x180 mm/memory.c:5069 but task is already holding lock: ffff8880b9c3a4b0 (&cpuctx_mutex){+.+.}-{3:3}, at: perf_event_ctx_lock_nested+0x26c/0x480 kernel/events/core.c:1356 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&cpuctx_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:949 [inline] __mutex_lock+0x139/0x1120 kernel/locking/mutex.c:1096 perf_event_init_cpu+0x172/0x3e0 kernel/events/core.c:13236 perf_event_init+0x39d/0x408 kernel/events/core.c:13283 start_kernel+0x2b6/0x496 init/main.c:1001 secondary_startup_64_no_verify+0xb0/0xbb -> #2 (pmus_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:949 [inline] __mutex_lock+0x139/0x1120 kernel/locking/mutex.c:1096 perf_event_init_cpu+0xc4/0x3e0 kernel/events/core.c:13230 cpuhp_invoke_callback+0x3b5/0x9a0 kernel/cpu.c:179 cpuhp_invoke_callback_range kernel/cpu.c:654 [inline] cpuhp_up_callbacks kernel/cpu.c:682 [inline] _cpu_up+0x3ab/0x6b0 kernel/cpu.c:1301 cpu_up kernel/cpu.c:1336 [inline] cpu_up+0xfe/0x1a0 kernel/cpu.c:1308 bringup_nonboot_cpus+0xfe/0x130 kernel/cpu.c:1398 smp_init+0x2e/0x145 kernel/smp.c:1090 kernel_init_freeable+0x402/0x6cc init/main.c:1552 kernel_init+0xd/0x1b8 init/main.c:1447 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> #1 (cpu_hotplug_lock){++++}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] cpus_read_lock+0x40/0x130 kernel/cpu.c:297 __static_key_slow_dec kernel/jump_label.c:254 [inline] static_key_slow_dec+0x4f/0xc0 kernel/jump_label.c:270 sw_perf_event_destroy+0x99/0x140 kernel/events/core.c:9544 _free_event+0x2ee/0x1380 kernel/events/core.c:4949 put_event kernel/events/core.c:5043 [inline] perf_mmap_close+0x572/0xe10 kernel/events/core.c:6088 remove_vma+0xae/0x170 mm/mmap.c:186 remove_vma_list mm/mmap.c:2659 [inline] __do_munmap+0x74f/0x11a0 mm/mmap.c:2915 do_munmap mm/mmap.c:2923 [inline] munmap_vma_range mm/mmap.c:604 [inline] mmap_region+0x85a/0x1730 mm/mmap.c:1756 do_mmap+0xcff/0x11d0 mm/mmap.c:1587 vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519 ksys_mmap_pgoff+0x4a8/0x620 mm/mmap.c:1638 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #0 (&mm->mmap_lock#2){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:2938 [inline] check_prevs_add kernel/locking/lockdep.c:3061 [inline] validate_chain kernel/locking/lockdep.c:3676 [inline] __lock_acquire+0x2a17/0x5230 kernel/locking/lockdep.c:4902 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __might_fault mm/memory.c:5070 [inline] __might_fault+0x106/0x180 mm/memory.c:5055 _copy_to_user+0x27/0x150 lib/usercopy.c:28 copy_to_user include/linux/uaccess.h:200 [inline] _perf_ioctl+0x882/0x2650 kernel/events/core.c:5603 perf_ioctl+0x76/0xb0 kernel/events/core.c:5683 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: &mm->mmap_lock#2 --> pmus_lock --> &cpuctx_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpuctx_mutex); lock(pmus_lock); lock(&cpuctx_mutex); lock(&mm->mmap_lock#2); *** DEADLOCK *** 1 lock held by syz-executor.0/26566: #0: ffff8880b9c3a4b0 (&cpuctx_mutex){+.+.}-{3:3}, at: perf_event_ctx_lock_nested+0x26c/0x480 kernel/events/core.c:1356 stack backtrace: CPU: 1 PID: 26566 Comm: syz-executor.0 Not tainted 5.13.0-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:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2129 check_prev_add kernel/locking/lockdep.c:2938 [inline] check_prevs_add kernel/locking/lockdep.c:3061 [inline] validate_chain kernel/locking/lockdep.c:3676 [inline] __lock_acquire+0x2a17/0x5230 kernel/locking/lockdep.c:4902 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __might_fault mm/memory.c:5070 [inline] __might_fault+0x106/0x180 mm/memory.c:5055 _copy_to_user+0x27/0x150 lib/usercopy.c:28 copy_to_user include/linux/uaccess.h:200 [inline] _perf_ioctl+0x882/0x2650 kernel/events/core.c:5603 perf_ioctl+0x76/0xb0 kernel/events/core.c:5683 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 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:00007f021b976188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000020000000 RSI: 0000000080082407 RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffdd1a9f15f R14: 00007f021b976300 R15: 0000000000022000