INFO: task syz-executor.1:30611 blocked for more than 143 seconds. Not tainted 5.12.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27232 pid:30611 ppid: 8455 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0x916/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 register_shrinker_prepared mm/vmscan.c:604 [inline] register_shrinker+0x4f/0x150 mm/vmscan.c:616 nfsd_reply_cache_init+0x243/0x4c0 fs/nfsd/nfscache.c:185 nfsd_init_net+0x20b/0x670 fs/nfsd/nfsctl.c:1473 ops_init+0xaf/0x470 net/core/net_namespace.c:140 setup_net+0x40f/0xa30 net/core/net_namespace.c:333 copy_net_ns+0x31e/0x760 net/core/net_namespace.c:474 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x8e0 kernel/fork.c:2996 __do_sys_unshare kernel/fork.c:3064 [inline] __se_sys_unshare kernel/fork.c:3062 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3062 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 RSP: 002b:00007fc4ba099188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc6e1088ef R14: 00007fc4ba099300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1632: #0: ffffffff8bf79760 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 3 locks held by khugepaged/1650: 1 lock held by in:imklog/8144: #0: ffff888019bf94f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by kworker/u4:12/12969: 1 lock held by systemd-udevd/2057: #0: ffff8880292ae460 (sb_writers#3){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3274 [inline] #0: ffff8880292ae460 (sb_writers#3){.+.+}-{0:0}, at: path_openat+0x25dd/0x27e0 fs/namei.c:3491 1 lock held by systemd-udevd/2088: 2 locks held by systemd-udevd/2144: 3 locks held by systemd-udevd/2166: 3 locks held by systemd-udevd/2753: 1 lock held by systemd-udevd/2886: 2 locks held by syz-executor.1/30611: #0: ffffffff8d6915d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker_prepared mm/vmscan.c:604 [inline] #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker+0x4f/0x150 mm/vmscan.c:616 2 locks held by syz-executor.1/30690: #0: ffffffff8d6915d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker_prepared mm/vmscan.c:604 [inline] #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker+0x4f/0x150 mm/vmscan.c:616 2 locks held by syz-executor.2/30660: #0: ffffffff8d6915d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker_prepared mm/vmscan.c:604 [inline] #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker+0x4f/0x150 mm/vmscan.c:616 2 locks held by syz-executor.2/30665: #0: ffffffff8d6915d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker_prepared mm/vmscan.c:604 [inline] #1: ffffffff8c05f250 (shrinker_rwsem){++++}-{3:3}, at: register_shrinker+0x4f/0x150 mm/vmscan.c:616 1 lock held by ifupdown-hotplu/3733: 1 lock held by systemd-sysctl/3734: 2 locks held by ifupdown-hotplu/3735: #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1334 [inline] #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x23e0 kernel/sched/core.c:5061 #1: ffff8880b9c1f988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x24c/0x670 kernel/sched/psi.c:872 4 locks held by ifupdown-hotplu/3745: #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1334 [inline] #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x23e0 kernel/sched/core.c:5061 #1: ffff8880b9d1f988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x24c/0x670 kernel/sched/psi.c:872 #2: ffff888015fa20b8 (&sig->wait_chldexit){....}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137 #3: ffff888017a7d958 (&ep->lock){.-.-}-{2:2}, at: ep_poll_callback+0x75/0xf40 fs/eventpoll.c:1136 2 locks held by systemd-sysctl/3758: #0: ffff888033f2ce58 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #0: ffff888033f2ce58 (&mm->mmap_lock#2){++++}-{3:3}, at: do_mprotect_pkey+0x1e0/0xa50 mm/mprotect.c:541 #1: ffff8880b9c1f988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x24c/0x670 kernel/sched/psi.c:872 2 locks held by systemd-sysctl/3778: 2 locks held by systemd-udevd/3780: 1 lock held by systemd-sysctl/3781: 1 lock held by systemd-sysctl/3782: 1 lock held by ifquery/3784: #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1334 [inline] #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x23e0 kernel/sched/core.c:5061 1 lock held by ifupdown-hotplu/3786: 2 locks held by systemd-sysctl/3791: 2 locks held by systemd-udevd/3792: #0: ffff888092666040 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: prepare_bprm_creds fs/exec.c:1463 [inline] #0: ffff888092666040 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0xb2/0x19a0 fs/exec.c:1798 #1: ffff8880b9c35258 (&rq->lock){-.-.}-{2:2}, at: fs_reclaim_acquire+0xb2/0x160 mm/page_alloc.c:4390 1 lock held by systemd-sysctl/3796: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1632 Comm: khungtaskd Not tainted 5.12.0-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 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:50 [inline] RIP: 0010:__unwind_start+0x565/0x800 arch/x86/kernel/unwind_orc.c:697 Code: ff ff 41 80 7d 00 00 0f 85 3d 01 00 00 41 80 3c 24 00 49 8b 47 08 0f 85 15 01 00 00 48 39 c3 49 8b 57 10 72 b3 48 39 d3 73 ae <48> 8d 4b 08 48 39 ca 72 a5 48 39 c8 73 a0 4c 89 f0 48 c1 e8 03 80 RSP: 0018:ffffc90000d27860 EFLAGS: 00000283 RAX: ffffc90000d20000 RBX: ffffc90000d27938 RCX: ffffc90000d28000 RDX: ffffc90000d28000 RSI: 1ffff920001a4f18 RDI: ffffc90000d27860 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffc90000d278b0 R10: fffff520001a4f21 R11: 000000000000003f R12: fffff520001a4f18 R13: fffff520001a4f17 R14: ffffc90000d278e8 R15: ffffc90000d278b0 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0076d05930 CR3: 00000000227ff000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0x5c/0xe0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1581 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1606 slab_free mm/slub.c:3166 [inline] kmem_cache_free+0x8a/0x740 mm/slub.c:3182 rcu_do_batch kernel/rcu/tree.c:2558 [inline] rcu_core+0x7ab/0x13b0 kernel/rcu/tree.c:2793 __do_softirq+0x29b/0x9f6 kernel/softirq.c:559 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:165 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294