INFO: task syz-executor:4268 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:22064 pid:4268 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 io_schedule+0x7c/0xd0 kernel/sched/core.c:8798 folio_wait_bit_common+0x70a/0xfa0 mm/filemap.c:1324 __filemap_get_folio+0x423/0xdb0 mm/filemap.c:1959 truncate_inode_pages_range+0x402/0x1090 mm/truncate.c:402 evict+0x4dc/0x8d0 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x60c/0x6a0 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+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 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:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7feac839d9d7 RSP: 002b:00007ffdbf1fc898 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007feac8432050 RCX: 00007feac839d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdbf1fc950 RBP: 00007ffdbf1fc950 R08: 00007ffdbf1fd950 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdbf1fd9e0 R13: 00007feac8432050 R14: 000000000002ecab R15: 00007ffdbf1fda20 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2dfb0 (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: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 3 locks held by ksoftirqd/1/21: 1 lock held by khungtaskd/27: #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4033: #0: ffff8880302cc098 (&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+0x429/0x1390 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4268: #0: ffff8880556e00e0 (&type->s_umount_key#72){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz-executor/7578: #0: ffff8880730720e0 (&type->s_umount_key#60){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz.5.2154/10028: #0: ffffffff8cb331c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 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 0 to CPUs 1: net_ratelimit: 5301 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:3a:1e:b7:7f:3a:c3, vlan:0) NMI backtrace for cpu 1 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:234 Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 0f 1f 80 00 00 00 00 48 8b 04 24 65 48 8b 15 24 fc 7f 7e 65 8b RSP: 0018:ffffc900001b6808 EFLAGS: 00000246 RAX: ffffffff8a1df2eb RBX: dffffc0000000000 RCX: ffff888017751dc0 RDX: 0000000000000100 RSI: ffffffff8e08efa0 RDI: 000000000000005d RBP: ffffffff8a8cd94b R08: ffff888017751dc0 R09: 0000000000000002 R10: 0000000000000025 R11: 0000000000000100 R12: ffffc900801b6b5f R13: ffff0a1000000609 R14: ffffffff8a8cd94b R15: 000000000000005d FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb55e5e7158 CR3: 000000000c88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: format_decode+0x14b/0x1300 lib/vsprintf.c:2539 vsnprintf+0xef/0x1c20 lib/vsprintf.c:2757 sprintf+0xe4/0x140 lib/vsprintf.c:3009 print_time kernel/printk/printk.c:1274 [inline] info_print_prefix+0x168/0x360 kernel/printk/printk.c:1300 record_print_text+0x173/0x440 kernel/printk/printk.c:1349 console_emit_next_record+0x598/0xba0 kernel/printk/printk.c:2760 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303 _printk+0xda/0x130 kernel/printk/printk.c:2328 br_fdb_update+0x572/0x5b0 net/bridge/br_fdb.c:860 br_handle_frame_finish+0x5c9/0x1670 net/bridge/br_input.c:124 br_nf_hook_thresh+0x3c9/0x4a0 net/bridge/br_netfilter_hooks.c:1184 br_nf_pre_routing_finish_ipv6+0x9da/0xd00 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:302 [inline] br_nf_pre_routing_ipv6+0x345/0x6b0 net/bridge/br_netfilter_ipv6.c:243 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:260 [inline] br_handle_frame+0x1167/0x13c0 net/bridge/br_input.c:406 __netif_receive_skb_core+0x1004/0x38f0 net/core/dev.c:5501 __netif_receive_skb_one_core net/core/dev.c:5605 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5721 process_backlog+0x38d/0x6f0 net/core/dev.c:6049 __napi_poll+0xc0/0x460 net/core/dev.c:6616 napi_poll net/core/dev.c:6683 [inline] net_rx_action+0x5dd/0xb20 net/core/dev.c:6797 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x64a/0xa40 kernel/smpboot.c:164 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295