INFO: task syz-executor:5897 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:21480 pid:5897 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:199 __wait_on_bit+0xac/0x2d0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1380 gfs2_glock_nq_init fs/gfs2/glock.h:252 [inline] __gfs2_lookup+0x118/0x270 fs/gfs2/inode.c:905 __lookup_slow+0x281/0x3b0 fs/namei.c:1702 lookup_slow+0x53/0x70 fs/namei.c:1719 walk_component+0x2be/0x3f0 fs/namei.c:2010 lookup_last fs/namei.c:2467 [inline] path_lookupat+0x169/0x440 fs/namei.c:2491 filename_lookup+0x1f4/0x510 fs/namei.c:2520 user_path_at_empty+0x42/0x60 fs/namei.c:2917 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1921 [inline] __do_sys_umount fs/namespace.c:1929 [inline] __se_sys_umount fs/namespace.c:1927 [inline] __x64_sys_umount+0xf5/0x170 fs/namespace.c:1927 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fdd48f90a77 RSP: 002b:00007fffaeaf3938 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007fdd49013d7d RCX: 00007fdd48f90a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffaeaf39f0 RBP: 00007fffaeaf39f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffaeaf4ae0 R13: 00007fdd49013d7d R14: 000055558d02c4a8 R15: 00007fffaeaf6ca0 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5528: #0: ffff88802d1550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 1 lock held by syz-executor/5897: #0: ffff88805fc2b068 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:814 [inline] #0: ffff88805fc2b068 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1718 1 lock held by syz.1.194/6507: 1 lock held by syz.1.195/6508: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11 Comm: kworker/u4:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__stack_depot_save+0x9/0x630 lib/stackdepot.c:361 Code: 89 d9 48 d3 e0 48 83 c4 08 5b c3 be 01 00 00 00 48 c7 c7 a0 b7 3e 8d 48 89 da e8 e2 62 00 00 eb da f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 83 ec 20 41 89 cf 89 d5 48 89 fb e8 91 d5 22 fd RSP: 0000:ffffc90000107740 EFLAGS: 00000246 RAX: 000000000000000b RBX: 0000000000000820 RCX: 0000000000000001 RDX: 0000000000000820 RSI: 000000000000000b RDI: ffffc90000107760 RBP: ffffc90000107988 R08: ffff88801be43c00 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 00000000000000f0 R14: ffff88802e5d5730 R15: ffffc90000107760 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f90a0f78000 CR3: 000000002dd7d000 CR4: 00000000003506f0 Call Trace: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x5f/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x150/0x330 mm/slub.c:3540 __alloc_skb+0x108/0x2c0 net/core/skbuff.c:643 alloc_skb include/linux/skbuff.h:1284 [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+0x293/0xb00 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293