INFO: task syz-executor:4270 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21792 pid:4270 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324 truncate_inode_pages_range+0x9a2/0xff0 mm/truncate.c:422 evict+0x498/0x870 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x604/0x690 fs/inode.c:792 generic_shutdown_super+0x93/0x340 fs/super.c:480 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1191 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2095b902f7 RSP: 002b:00007fff20ce8368 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f2095c11d7d RCX: 00007f2095b902f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff20ce8420 RBP: 00007fff20ce8420 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff20ce94b0 R13: 00007f2095c11d7d R14: 000000000002f39d R15: 00007fff20ce94f0 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 3 locks held by kworker/u4:4/63: 2 locks held by getty/4031: #0: ffff88802fa9e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4270: #0: ffff888077bd00e0 (&type->s_umount_key#86){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 3 locks held by kworker/0:8/4345: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc900044c7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff888066c09240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26b/0x32b0 drivers/net/netdevsim/fib.c:1491 5 locks held by syz-executor/12139: 2 locks held by dhcpcd-run-hook/12141: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12139 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65 Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 RSP: 0018:ffffc90003296fc8 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffffc900032970a8 RCX: 0000000000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003297108 RBP: ffffffff8ea7eb7a R08: dffffc0000000000 R09: ffffc900032970f8 R10: fffff52000652e21 R11: 1ffff92000652e1f R12: 1ffff92000652e16 R13: dffffc0000000000 R14: ffffc900032970f8 R15: ffffc900032970dd FS: 0000555577fe8500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8b387fe440 CR3: 000000006071c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node_track_caller+0xae/0x230 mm/slab_common.c:956 kstrdup mm/util.c:61 [inline] kstrdup_const+0x56/0x90 mm/util.c:84 __kernfs_new_node+0x99/0x7d0 fs/kernfs/dir.c:610 kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:690 kernfs_create_dir_ns+0x40/0x120 fs/kernfs/dir.c:1046 sysfs_create_dir_ns+0x120/0x280 fs/sysfs/dir.c:59 create_dir lib/kobject.c:63 [inline] kobject_add_internal+0x6b8/0xc80 lib/kobject.c:231 kobject_add_varg lib/kobject.c:366 [inline] kobject_add+0x152/0x210 lib/kobject.c:418 device_add+0x483/0xfb0 drivers/base/core.c:3632 netdev_register_kobject+0x176/0x310 net/core/net-sysfs.c:2013 register_netdevice+0x12b9/0x1aa0 net/core/dev.c:10204 register_netdev+0x37/0x50 net/core/dev.c:10332 ip6gre_init_net+0x263/0x360 net/ipv6/ip6_gre.c:1648 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 setup_net+0x4e1/0xbb0 net/core/net_namespace.c:336 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226 ksys_unshare+0x4bc/0x890 kernel/fork.c:3277 __do_sys_unshare kernel/fork.c:3348 [inline] __se_sys_unshare kernel/fork.c:3346 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3346 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff7d33907c7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff95a95718 EFLAGS: 00000206 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007ff7d35e5f40 RCX: 00007ff7d33907c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007ff7d35e67b8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000