INFO: task syz-executor:5831 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21328 pid:5831 tgid:5831 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit include/linux/wait_bit.h:77 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1269 gfs2_glock_nq_init fs/gfs2/glock.h:253 [inline] __gfs2_lookup+0x134/0x2a0 fs/gfs2/inode.c:999 __lookup_slow+0x2b7/0x410 fs/namei.c:1916 lookup_slow+0x53/0x70 fs/namei.c:1933 walk_component fs/namei.c:2279 [inline] lookup_last fs/namei.c:2780 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2804 filename_lookup+0x256/0x5d0 fs/namei.c:2833 user_path_at+0x40/0x160 fs/namei.c:3612 ksys_umount fs/namespace.c:2052 [inline] __do_sys_umount fs/namespace.c:2060 [inline] __se_sys_umount fs/namespace.c:2058 [inline] __x64_sys_umount+0xf6/0x170 fs/namespace.c:2058 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f4299c117 RSP: 002b:00007ffecc02dd78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f0f42a0471f RCX: 00007f0f4299c117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffecc02de30 RBP: 00007ffecc02de30 R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffecc02ef20 R13: 00007f0f42a0471f R14: 000000000008a236 R15: 00007ffecc0310e0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5578: #0: ffff8880326f00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5831: #0: ffff88806a9907e8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88806a9907e8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 2 locks held by syz.1.2559/14687: #0: ffffffff8fbb8e50 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577 #1: ffffffff8e766480 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 1 lock held by syz.0.2569/14712: #0: ffffffff8e766480 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 1 lock held by syz.6.2568/14715: #0: ffffffff8e766480 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:347 [inline] watchdog+0x103d/0x1090 kernel/hung_task.c:516 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 14716 Comm: syz.6.2568 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:__rcu_read_unlock+0x60/0xe0 kernel/rcu/tree_plugin.h:441 Code: ff 0b 75 1d 4c 8d b7 88 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 66 41 83 3e 00 75 27 43 0f b6 04 3c 84 c0 75 41 <8b> 03 3d 00 00 00 40 73 0f 5b 41 5c 41 5d 41 5e 41 5f e9 59 5f 05 RSP: 0018:ffffc900164ff0e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88803554a2c4 RCX: 0000000000000046 RDX: 0000000000000001 RSI: ffffffff8e15d4e2 RDI: ffff888035549e40 RBP: 0000000000000000 R08: ffffffff81d53ef6 R09: ffffffff8e760320 R10: ffffc900164ff1f8 R11: ffffffff81b0c240 R12: 1ffff11006aa9458 R13: dffffc0000000000 R14: ffff88803554a2c8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff88812556a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30a04ff8 CR3: 0000000075cb2000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:883 [inline] is_bpf_text_address+0x292/0x2b0 kernel/bpf/core.c:750 kernel_text_address+0xa5/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5294 kmalloc_noprof include/linux/slab.h:962 [inline] slab_free_hook mm/slub.c:2619 [inline] slab_free mm/slub.c:6079 [inline] kmem_cache_free+0x15b/0x630 mm/slub.c:6209 anon_vma_free mm/rmap.c:137 [inline] __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2892 put_anon_vma mm/internal.h:215 [inline] unlink_anon_vmas+0x58b/0x730 mm/rmap.c:529 free_pgtables+0x836/0xb70 mm/memory.c:429 exit_mmap+0x482/0xa00 mm/mmap.c:1314 __mmput+0x118/0x430 kernel/fork.c:1174 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2310 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efe39f9aeb9 Code: Unable to access opcode bytes at 0x7efe39f9ae8f. RSP: 002b:00007efe3aee90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007efe3a215fa8 RCX: 00007efe39f9aeb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007efe3a215fa8 RBP: 00007efe3a215fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efe3a216038 R14: 00007ffee3d56bd0 R15: 00007ffee3d56cb8 ---------------- Code disassembly (best guess): 0: ff 0b decl (%rbx) 2: 75 1d jne 0x21 4: 4c 8d b7 88 04 00 00 lea 0x488(%rdi),%r14 b: 4c 89 f0 mov %r14,%rax e: 48 c1 e8 03 shr $0x3,%rax 12: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax 17: 84 c0 test %al,%al 19: 75 66 jne 0x81 1b: 41 83 3e 00 cmpl $0x0,(%r14) 1f: 75 27 jne 0x48 21: 43 0f b6 04 3c movzbl (%r12,%r15,1),%eax 26: 84 c0 test %al,%al 28: 75 41 jne 0x6b * 2a: 8b 03 mov (%rbx),%eax <-- trapping instruction 2c: 3d 00 00 00 40 cmp $0x40000000,%eax 31: 73 0f jae 0x42 33: 5b pop %rbx 34: 41 5c pop %r12 36: 41 5d pop %r13 38: 41 5e pop %r14 3a: 41 5f pop %r15 3c: e9 .byte 0xe9 3d: 59 pop %rcx 3e: 5f pop %rdi 3f: 05 .byte 0x5