INFO: task syz-executor:10292 blocked for more than 143 seconds. Not tainted 6.15.0-next-20250606-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21512 pid:10292 tgid:10292 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:237 __wait_on_bit+0xb6/0x310 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:77 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1351 gfs2_glock_nq_init fs/gfs2/glock.h:238 [inline] __gfs2_lookup+0x117/0x270 fs/gfs2/inode.c:987 __lookup_slow+0x297/0x3d0 fs/namei.c:1817 lookup_slow+0x53/0x70 fs/namei.c:1834 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2639 [inline] path_lookupat+0x163/0x430 fs/namei.c:2663 filename_lookup+0x212/0x570 fs/namei.c:2692 user_path_at+0x3a/0x60 fs/namei.c:3127 ksys_umount fs/namespace.c:2147 [inline] __do_sys_umount fs/namespace.c:2155 [inline] __se_sys_umount fs/namespace.c:2153 [inline] __x64_sys_umount+0xee/0x160 fs/namespace.c:2153 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f310038fc57 RSP: 002b:00007fff252d38b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f3100410925 RCX: 00007f310038fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff252d3970 RBP: 00007fff252d3970 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff252d4a60 R13: 00007f3100410925 R14: 00000000001147c5 R15: 00007fff252d6c20 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:8/2989: 2 locks held by getty/5596: #0: ffff888034ea20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/10292: #0: ffff888053af4ad8 (&type->i_mutex_dir_key#23){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:882 [inline] #0: ffff888053af4ad8 (&type->i_mutex_dir_key#23){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/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+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6107 Comm: kworker/u8:13 Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:unwind_next_frame+0x188/0x2390 arch/x86/kernel/unwind_orc.c:-1 Code: 8d 5e 35 48 89 d8 48 c1 e8 03 48 89 44 24 28 0f b6 04 28 84 c0 0f 85 3c 1b 00 00 4c 89 6c 24 50 4c 89 64 24 20 4c 89 7c 24 48 <48> 89 5c 24 10 0f b6 1b 48 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 18 RSP: 0018:ffffc9000b877438 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc9000b87753d RCX: 6c651d3aa1dfe400 RDX: 0000000000000000 RSI: ffffffff8be2a860 RDI: ffffffff8be2a820 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81729de5 R10: ffffc9000b877558 R11: ffffffff81acf980 R12: 1ffff9200170eea1 R13: ffffc9000b877558 R14: ffffc9000b877508 R15: ffffffff81729de5 FS: 0000000000000000(0000) GS:ffff888125c4d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd7d90ec88 CR3: 00000000343a4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4347 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [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+0x29a/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245