INFO: task syz-executor:5816 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:21320 pid:5816 tgid:5816 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: 0033:0x7f528699c117 RSP: 002b:00007ffc84cd89a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f5286a0471f RCX: 00007f528699c117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc84cd8a60 RBP: 00007ffc84cd8a60 R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc84cd9b50 R13: 00007f5286a0471f R14: 0000000000069470 R15: 00007ffc84cdbd10 Showing all locks held in the system: 1 lock held by rcu_exp_gp_kthr/18: 1 lock held by khungtaskd/30: #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 3 locks held by kworker/u8:2/35: #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #2: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #2: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline] #2: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x23c0 arch/x86/kernel/unwind_orc.c:495 2 locks held by getty/5571: #0: ffff8880377340a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036be2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5816: #0: ffff88806d93a268 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88806d93a268 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 3 locks held by kworker/u8:11/7093: #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff888059c00788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline] #2: ffff888059c00788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x4a0 net/wireless/core.c:426 3 locks held by kworker/u8:12/8511: #0: ffff88801b0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc9001b4b7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 #2: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 2 locks held by syz.4.1795/12391: 2 locks held by syz.2.1803/12408: #0: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 #1: ffffffff8e7665b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e7665b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.3.1809/12425: #0: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bc/0x1e30 drivers/net/tun.c:3078 1 lock held by syz.3.1809/12430: #0: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120 2 locks held by syz.6.1810/12428: #0: ffffffff8f37e948 (ppp_mutex){+.+.}-{4:4}, at: ppp_ioctl+0xdf/0x1b10 drivers/net/ppp/ppp_generic.c:734 #1: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: ppp_create_interface drivers/net/ppp/ppp_generic.c:3392 [inline] #1: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1065 [inline] #1: ffffffff8fbc7d08 (rtnl_mutex){+.+.}-{4:4}, at: ppp_ioctl+0x6ce/0x1b10 drivers/net/ppp/ppp_generic.c:738 1 lock held by syz.6.1810/12432: #0: ffffffff8f37e948 (ppp_mutex){+.+.}-{4:4}, at: ppp_ioctl+0xdf/0x1b10 drivers/net/ppp/ppp_generic.c:734 1 lock held by syz.6.1810/12436: #0: ffffffff8f37e948 (ppp_mutex){+.+.}-{4:4}, at: ppp_ioctl+0xdf/0x1b10 drivers/net/ppp/ppp_generic.c:734 1 lock held by syz.1.1812/12441: #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: 30 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: 6728 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:check_preemption_disabled+0x29/0xe0 lib/smp_processor_id.c:19 Code: 90 55 41 57 41 56 53 65 8b 05 57 63 6d 07 65 8b 0d 4c 63 6d 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 9c <59> f7 c1 00 02 00 00 74 ea 65 4c 8b 3d fe 62 6d 07 41 f6 47 2f 04 RSP: 0018:ffffc9001b9fe9e0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000202 RCX: 0000000080000000 RDX: ffffc9001b9feb01 RSI: ffffffff8df067c2 RDI: ffffffff8c277400 RBP: dffffc0000000000 R08: ffffc9001b9ff610 R09: 0000000000000000 R10: ffffc9001b9feb98 R11: fffff5200373fd75 R12: ffffc9001b9ff620 R13: ffffffff81768a45 R14: ffffffff8e760320 R15: ffff8880413d9e40 FS: 0000000000000000(0000) GS:ffff88812556a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff377cddf0 CR3: 00000000665a4000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline] lock_release+0xa1/0x3d0 kernel/locking/lockdep.c:5888 rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock include/linux/rcupdate.h:881 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 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] __do_kmalloc_node mm/slub.c:5174 [inline] __kmalloc_noprof+0x35c/0x760 mm/slub.c:5186 kmalloc_noprof include/linux/slab.h:966 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] cfg80211_inform_single_bss_data+0x952/0x1b70 net/wireless/scan.c:2345 cfg80211_inform_bss_data+0x266/0x3c40 net/wireless/scan.c:3228 cfg80211_inform_bss_frame_data+0x3c7/0x760 net/wireless/scan.c:3319 ieee80211_bss_info_update+0x794/0xa40 net/mac80211/scan.c:230 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline] ieee80211_ibss_rx_queued_mgmt+0x1901/0x2cd0 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1748 [inline] ieee80211_iface_work+0x84e/0x1340 net/mac80211/iface.c:1802 cfg80211_wiphy_work+0x2ab/0x4a0 net/wireless/core.c:440 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 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 ---------------- Code disassembly (best guess): 0: 90 nop 1: 55 push %rbp 2: 41 57 push %r15 4: 41 56 push %r14 6: 53 push %rbx 7: 65 8b 05 57 63 6d 07 mov %gs:0x76d6357(%rip),%eax # 0x76d6365 e: 65 8b 0d 4c 63 6d 07 mov %gs:0x76d634c(%rip),%ecx # 0x76d6361 15: f7 c1 ff ff ff 7f test $0x7fffffff,%ecx 1b: 74 0c je 0x29 1d: 5b pop %rbx 1e: 41 5e pop %r14 20: 41 5f pop %r15 22: 5d pop %rbp 23: c3 ret 24: cc int3 25: cc int3 26: cc int3 27: cc int3 28: cc int3 29: 9c pushf * 2a: 59 pop %rcx <-- trapping instruction 2b: f7 c1 00 02 00 00 test $0x200,%ecx 31: 74 ea je 0x1d 33: 65 4c 8b 3d fe 62 6d mov %gs:0x76d62fe(%rip),%r15 # 0x76d6339 3a: 07 3b: 41 f6 47 2f 04 testb $0x4,0x2f(%r15)