INFO: task syz.8.2914:19358 blocked for more than 143 seconds. Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.2914 state:D stack:25520 pid:19358 tgid:19358 ppid:18656 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216 sync_inodes_sb+0x28d/0xb50 fs/fs-writeback.c:2821 sync_filesystem+0x176/0x230 fs/sync.c:64 generic_shutdown_super+0x72/0x2d0 fs/super.c:621 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xc6/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x251/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3017 arch_do_signal_or_restart+0x96/0x860 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:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 00fb:0x294e66b3c7c44cb4 RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753 RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1 R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by getty/5586: #0: ffff88814e5f80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:9/5975: #0: ffff8880206d6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff8880206d6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90003417d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003417d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 3 locks held by kworker/u8:11/7165: #0: ffff8880b863e8d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987 #2: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xed/0x270 kernel/sched/psi.c:912 2 locks held by syz.8.2914/19358: #0: ffff888040f360e0 (&type->s_umount_key#93){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888040f360e0 (&type->s_umount_key#93){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888040f360e0 (&type->s_umount_key#93){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff8881433387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8881433387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819 1 lock held by segctord/23361: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10718 Comm: kworker/u8:17 Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:unwind_next_frame+0xb01/0x22d0 arch/x86/kernel/unwind_orc.c:581 Code: 48 0f bf 02 48 01 04 24 49 8d 6f 01 48 8b 44 24 70 42 0f b6 04 20 84 c0 0f 85 39 11 00 00 48 89 eb 48 c1 eb 03 42 0f b6 04 23 <84> c0 0f 85 45 11 00 00 41 0f b6 77 01 83 e6 07 83 fe 04 0f 84 e6 RSP: 0018:ffffc900035974b0 EFLAGS: 00000213 RAX: 0000000000000000 RBX: 1ffffffff21482ad RCX: ffffffff902cfc7c RDX: ffffffff90a4156a RSI: ffffffff90a4156a RDI: 0000000000000001 RBP: ffffffff90a4156f R08: 0000000000000001 R09: ffffc90003597670 R10: dffffc0000000000 R11: ffffffff818b36f0 R12: dffffc0000000000 R13: ffffc90003597580 R14: ffffc900035975b8 R15: ffffffff90a4156e FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556aa3b30680 CR3: 000000000e736000 CR4: 0000000000350ef0 Call Trace: arch_stack_walk+0x11c/0x150 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 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4283 [inline] __kmalloc_node_track_caller_noprof+0x28b/0x4c0 mm/slub.c:4302 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1323 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x261/0xb50 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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