INFO: task syz.6.1123:9556 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.1123 state:D stack:23784 pid:9556 ppid:8892 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 perf_pending_task_sync kernel/events/core.c:5242 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5248 put_event kernel/events/core.c:5376 [inline] perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501 perf_release+0x3b/0x40 kernel/events/core.c:5511 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 get_signal+0x1235/0x1400 kernel/signal.c:2678 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f975218eba9 RSP: 002b:00007f975307ffe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f97523d5fa0 RCX: 00007f975218eba9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000043001000 RBP: 00007f9752211e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f97523d6038 R14: 00007f97523d5fa0 R15: 00007ffe29577b18 Showing all locks held in the system: 3 locks held by kworker/u4:0/11: 1 lock held by khungtaskd/29: #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5553: #0: ffff88814dc400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by kworker/1:11/7842: #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000bcbfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000bcbfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 3 locks held by syz.9.1518/11259: #0: ffffffff8dfaf810 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x351/0x5e0 net/core/net_namespace.c:516 #1: ffffffff8dfbc648 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0xc3/0x490 net/ipv6/ip6_gre.c:1644 #2: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #2: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004 2 locks held by syz.8.1512/11272: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10316 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5492 [inline] RIP: 0010:lock_is_held_type+0xae/0x190 kernel/locking/lockdep.c:5825 Code: 00 00 00 7e 4b 44 89 fd 49 89 df 49 81 c7 e0 0a 00 00 45 31 e4 49 83 fc 31 73 24 4c 89 ff 4c 89 f6 e8 26 02 00 00 85 c0 75 2a <49> ff c4 48 63 83 d8 0a 00 00 49 83 c7 28 49 39 c4 7c d8 eb 11 48 RSP: 0018:ffffc900051c74a0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880232fbc00 RCX: 0000000000000000 RDX: ffff8880232fbc00 RSI: ffffffff8cd2fc20 RDI: ffff8880232fc708 RBP: 00000000ffffffff R08: dffffc0000000000 R09: 1ffffffff21b4aa0 R10: dffffc0000000000 R11: fffffbfff21b4aa1 R12: 0000000000000001 R13: 0000000000000246 R14: ffffffff8cd2fc20 R15: ffff8880232fc708 FS: 0000555581eeb500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000c10000 CR3: 00000000523df000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: xa_head include/linux/xarray.h:1200 [inline] xas_start+0x292/0x770 lib/xarray.c:190 xas_load lib/xarray.c:237 [inline] xa_load+0x126/0x2e0 lib/xarray.c:1461 list_lru_from_memcg_idx mm/list_lru.c:56 [inline] list_lru_from_kmem mm/list_lru.c:78 [inline] list_lru_del+0x1a7/0x3c0 mm/list_lru.c:151 d_lru_del fs/dcache.c:445 [inline] select_collect+0x130/0x400 fs/dcache.c:1570 d_walk+0x1dc/0x700 fs/dcache.c:1391 shrink_dcache_parent+0xfb/0x3c0 fs/dcache.c:1630 d_invalidate+0x11c/0x260 fs/dcache.c:1741 proc_invalidate_siblings_dcache+0x3d3/0x6c0 fs/proc/inode.c:148 release_task+0x145b/0x1610 kernel/exit.c:279 wait_task_zombie kernel/exit.c:1210 [inline] wait_consider_task+0x1992/0x2ea0 kernel/exit.c:1437 do_wait_thread kernel/exit.c:1500 [inline] do_wait+0x2f8/0xaf0 kernel/exit.c:1617 kernel_wait4+0x1af/0x270 kernel/exit.c:1780 __do_sys_wait4 kernel/exit.c:1808 [inline] __se_sys_wait4 kernel/exit.c:1804 [inline] __x64_sys_wait4+0x134/0x1e0 kernel/exit.c:1804 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe9a0384e17 Code: 89 7c 24 10 48 89 4c 24 18 e8 45 1b 03 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 95 1b 03 00 8b 44 RSP: 002b:00007ffebe9947d0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 000000000000009a RCX: 00007fe9a0384e17 RDX: 0000000040000001 RSI: 00007ffebe99483c RDI: 00000000ffffffff RBP: 00007ffebe99483c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000001388 R13: 00000000000927c0 R14: 0000000000080880 R15: 00007ffebe994890