INFO: task syz.4.5:5378 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00015-g3e9bff3bbe13 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.5 state:D stack:24792 pid:5378 tgid:5370 ppid:5226 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:799 [inline] do_lock_mount+0x112/0x3a0 fs/namespace.c:2580 lock_mount fs/namespace.c:2622 [inline] do_new_mount_fc fs/namespace.c:3409 [inline] do_new_mount+0x43d/0xb40 fs/namespace.c:3474 do_mount fs/namespace.c:3812 [inline] __do_sys_mount fs/namespace.c:4020 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff33b179e79 RSP: 002b:00007ff33bee2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ff33b316058 RCX: 00007ff33b179e79 RDX: 0000000020000000 RSI: 0000000020000080 RDI: 0000000000000000 RBP: 00007ff33b1e793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff33b316058 R15: 00007ffffccf5848 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:3/53: 3 locks held by kworker/1:2/936: #0: ffff888015878948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015878948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003a9fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003a9fd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b08 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 5 locks held by kworker/u8:7/1113: #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004047d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004047d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc77f50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8fc84b08 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:630 #4: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #4: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 3 locks held by kworker/u8:11/2957: 3 locks held by kworker/u8:12/2969: #0: ffff88802aa4d148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88802aa4d148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009ed7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009ed7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4194 3 locks held by kworker/u8:13/3021: #0: ffff888015881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009dd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009dd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/4983: #0: ffff88802b5cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.4.5/5371: 1 lock held by syz.4.5/5378: #0: ffff88805cb28180 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline] #0: ffff88805cb28180 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: do_lock_mount+0x112/0x3a0 fs/namespace.c:2580 1 lock held by syz.1.311/6882: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00015-g3e9bff3bbe13 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 4679 Comm: udevd Not tainted 6.11.0-rc5-syzkaller-00015-g3e9bff3bbe13 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:unwind_next_frame+0x3c/0x2a00 arch/x86/kernel/unwind_orc.c:470 Code: 00 00 00 48 89 fd 49 bd 00 00 00 00 00 fc ff df e8 b9 64 52 00 48 8d 5d 48 48 89 d8 48 c1 e8 03 48 89 44 24 30 42 80 3c 28 00 <74> 08 48 89 df e8 6a a7 b9 00 48 89 5c 24 20 4c 8b 7d 48 48 8d 5d RSP: 0018:ffffc90009267648 EFLAGS: 00000046 RAX: 1ffff9200124ceed RBX: ffffc90009267768 RCX: ffff88807e65da00 RDX: 0000000000000000 RSI: ffffffff817cf96d RDI: ffffc90009267720 RBP: ffffc90009267720 R08: 000000000000000a R09: ffffc90009267810 R10: 0000000000000003 R11: ffffffff817f2f00 R12: ffff88807e65da00 R13: dffffc0000000000 R14: ffffc90009267800 R15: ffffc90009267720 FS: 00007f978f54dc80(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa056455423 CR3: 000000002d48c000 CR4: 0000000000350ef0 Call Trace: arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 __sigqueue_alloc+0x42e/0x540 kernel/signal.c:428 __send_signal_locked+0x22f/0xdc0 kernel/signal.c:1119 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1451 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_7ba5217f62dcd359+0x40/0x48 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline] bpf_trace_run2+0x2ee/0x540 kernel/trace/bpf_trace.c:2447 __traceiter_sys_enter+0x2d/0x50 include/trace/events/syscalls.h:18 trace_sys_enter+0x93/0xd0 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf8/0x150 kernel/entry/common.c:61 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline] syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline] do_syscall_64+0xcc/0x230 arch/x86/entry/common.c:79 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f978f0fc476 Code: 10 00 00 00 48 89 d1 89 f2 48 89 fe 83 cf ff e9 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 73 48 8b 15 83 49 0f 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffff1299eb8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f978f0fc476 RDX: 0000000000000001 RSI: 00007ffff1299f80 RDI: 00000000ffffffff RBP: 000000000000000b R08: 000000000e4b7ccd R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00005560b2374004 R13: 0000000200000001 R14: 0000000000000001 R15: 0000000000000000