====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/12294 is trying to acquire lock: 0000000003cadac1 (cpu_hotplug_lock.rw_sem){++++}, at: __static_key_slow_dec kernel/jump_label.c:222 [inline] 0000000003cadac1 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_dec+0x4f/0x90 kernel/jump_label.c:237 but task is already holding lock: 000000001c5216c2 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_sem){++++}: _copy_to_user+0x29/0x100 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] perf_read_group kernel/events/core.c:4831 [inline] __perf_read kernel/events/core.c:4898 [inline] perf_read+0x699/0x860 kernel/events/core.c:4913 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_readv+0x136/0x330 fs/read_write.c:1020 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&cpuctx_mutex){+.+.}: perf_event_init_cpu+0xc4/0x170 kernel/events/core.c:11828 perf_event_init+0x309/0x34e kernel/events/core.c:11875 start_kernel+0x5b1/0x911 init/main.c:644 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #1 (pmus_lock){+.+.}: perf_event_init_cpu+0x2c/0x170 kernel/events/core.c:11822 cpuhp_invoke_callback+0x201/0x1b80 kernel/cpu.c:170 cpuhp_up_callbacks kernel/cpu.c:584 [inline] _cpu_up+0x25c/0x540 kernel/cpu.c:1192 do_cpu_up+0xdd/0x1b0 kernel/cpu.c:1228 smp_init+0x1ed/0x202 kernel/smp.c:578 kernel_init_freeable+0x62b/0xab7 init/main.c:1138 kernel_init+0xd/0x1ba init/main.c:1062 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 (cpu_hotplug_lock.rw_sem){++++}: 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+0x3b/0xd0 kernel/cpu.c:290 __static_key_slow_dec kernel/jump_label.c:222 [inline] static_key_slow_dec+0x4f/0x90 kernel/jump_label.c:237 sw_perf_event_destroy+0x8a/0x120 kernel/events/core.c:8311 _free_event+0x32c/0x1150 kernel/events/core.c:4484 put_event kernel/events/core.c:4578 [inline] perf_mmap_close+0x6f6/0xea0 kernel/events/core.c:5582 remove_vma+0xa9/0x170 mm/mmap.c:176 remove_vma_list mm/mmap.c:2550 [inline] do_munmap+0x6f9/0xde0 mm/mmap.c:2786 mmap_region+0x2a3/0x16b0 mm/mmap.c:1700 do_mmap+0x8e8/0x1080 mm/mmap.c:1530 do_mmap_pgoff include/linux/mm.h:2329 [inline] vm_mmap_pgoff+0x197/0x200 mm/util.c:357 ksys_mmap_pgoff+0x298/0x5a0 mm/mmap.c:1580 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 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-executor.1/12294: #0: 000000001c5216c2 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 stack backtrace: CPU: 0 PID: 12294 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0 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+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 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+0x3b/0xd0 kernel/cpu.c:290 __static_key_slow_dec kernel/jump_label.c:222 [inline] static_key_slow_dec+0x4f/0x90 kernel/jump_label.c:237 sw_perf_event_destroy+0x8a/0x120 kernel/events/core.c:8311 _free_event+0x32c/0x1150 kernel/events/core.c:4484 put_event kernel/events/core.c:4578 [inline] perf_mmap_close+0x6f6/0xea0 kernel/events/core.c:5582 remove_vma+0xa9/0x170 mm/mmap.c:176 remove_vma_list mm/mmap.c:2550 [inline] do_munmap+0x6f9/0xde0 mm/mmap.c:2786 mmap_region+0x2a3/0x16b0 mm/mmap.c:1700 do_mmap+0x8e8/0x1080 mm/mmap.c:1530 UDF-fs: bad mount option "Chv¯o*B" or missing value do_mmap_pgoff include/linux/mm.h:2329 [inline] vm_mmap_pgoff+0x197/0x200 mm/util.c:357 ksys_mmap_pgoff+0x298/0x5a0 mm/mmap.c:1580 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fe1d7f54ae9 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:00007fe1d54a9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe1d8068020 RCX: 00007fe1d7f54ae9 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 RBP: 00007fe1d7faef6d R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdf886083f R14: 00007fe1d54a9300 R15: 0000000000022000 nla_parse: 3 callbacks suppressed netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. audit: type=1800 audit(1637558599.197:312): pid=12450 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed comm="syz-executor.4" name="cpuacct.usage_percpu_sys" dev="sda1" ino=14447 res=0 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: './bus' not a directory overlayfs: lowerdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.2'. nla_parse: 2 callbacks suppressed netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'.