INFO: task syz.6.3892:20739 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.3892 state:D stack:26280 pid:20739 tgid:20739 ppid:14500 task_flags:0x400640 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264 coredump_wait fs/coredump.c:504 [inline] do_coredump+0x8fa/0x4f10 fs/coredump.c:686 get_signal+0x22e3/0x26d0 kernel/signal.c:3019 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] irqentry_exit_to_user_mode+0x12a/0x270 kernel/entry/common.c:184 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f1134a4f837 RSP: 002b:00007ffecf722c20 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00000000001750c0 RDX: 00007ffecf722c40 RSI: 00007ffecf722d70 RDI: 000000000000000b RBP: 00007f1134db7ba0 R08: 0000000000048c9c R09: 00007f113590b000 R10: 0000000000000001 R11: 0020930acc915bf1 R12: 0000000000175e9e R13: 00007f1134db6080 R14: ffffffffffffffff R15: 00007ffecf81f850 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 2 locks held by getty/5579: #0: ffff888032ade0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:18/10951: #0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90003b5fd10 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff9034d2a8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303 2 locks held by syz.5.4427/22675: #0: ffffffff9034d2a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff9034d2a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3396 #1: ffffffff8e5cfe78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:304 1 lock held by syz.0.4431/22687: #0: ffffffff8e5cfd40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3782 1 lock held by syz.3.4432/22698: #0: ffffffff9034d2a8 (rtnl_mutex){+.+.}-{4:4}, at: start_sync_thread+0x120/0x28b0 net/netfilter/ipvs/ip_vs_sync.c:1761 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 22689 Comm: syz.0.4431 Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:find_stack lib/stackdepot.c:552 [inline] RIP: 0010:stack_depot_save_flags+0x14e/0xa40 lib/stackdepot.c:619 Code: c8 41 c1 c9 08 44 29 c8 41 89 c5 45 89 e9 44 23 0d 07 ad f9 15 49 c1 e1 04 4c 03 0d 04 ad f9 15 65 ff 05 25 01 bf 0e 49 8b 09 <49> 39 c9 75 11 e9 94 00 00 00 48 8b 09 49 39 c9 0f 84 32 02 00 00 RSP: 0018:ffffc90003177958 EFLAGS: 00000282 RAX: 00000000c1e41a02 RBX: 000000000000000c RCX: ffff888049982d60 RDX: 00000000cd9d5b49 RSI: 0000000000000003 RDI: 0000000054081c1e RBP: 0000000000000001 R08: 0000000000000001 R09: ffff88823b21a020 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000002000 R13: 00000000c1e41a02 R14: ffffc900031779e0 R15: 000000000000000c FS: 00007f30771bb6c0(0000) GS:ffff888124853000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c417ff8 CR3: 00000000441a5000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: save_stack+0x16d/0x1f0 mm/page_owner.c:157 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204 audit_buffer_alloc kernel/audit.c:1791 [inline] audit_log_start+0x2c5/0x7f0 kernel/audit.c:1913 audit_seccomp+0x60/0x290 kernel/auditsc.c:3001 seccomp_log kernel/seccomp.c:1033 [inline] __seccomp_filter+0x60e/0xea0 kernel/seccomp.c:1360 __secure_computing+0x287/0x3b0 kernel/seccomp.c:1388 syscall_trace_enter+0x89/0x260 kernel/entry/common.c:52 syscall_enter_from_user_mode_work include/linux/entry-common.h:170 [inline] syscall_enter_from_user_mode include/linux/entry-common.h:200 [inline] do_syscall_64+0x347/0x4c0 arch/x86/entry/syscall_64.c:90 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f307638e929 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f30771bb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f30765b5fa8 RCX: 00007f307638e929 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f30765b5fa8 RBP: 00007f30765b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f30765b5fac R13: 0000000000000000 R14: 00007ffc52662150 R15: 00007ffc52662238