INFO: task syz.0.47:6029 blocked for more than 184 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.47 state:D stack:24496 pid:6029 ppid:5780 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 do_uevent+0x1ed/0x490 fs/dlm/lockspace.c:210 new_lockspace fs/dlm/lockspace.c:633 [inline] __dlm_new_lockspace+0x1dca/0x2360 fs/dlm/lockspace.c:693 device_create_lockspace+0xc8/0x350 fs/dlm/user.c:430 device_write+0x875/0xed0 fs/dlm/user.c:622 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fca3699e019 RSP: 002b:00007fca37907028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fca36c25fa0 RCX: 00007fca3699e019 RDX: 0000000000000080 RSI: 0000200000000400 RDI: 0000000000000007 RBP: 00007fca36a3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fca36c26038 R14: 00007fca36c25fa0 R15: 00007ffee77df068 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by klogd/5126: 1 lock held by udevd/5137: 3 locks held by crond/5511: 2 locks held by getty/5527: #0: ffff88802d1320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 8 locks held by kworker/1:5/5809: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline] #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734 #1: ffffc900047afd00 (console_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline] #1: ffffc900047afd00 (console_work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734 #2: ffffffff8d126180 (console_lock){+.+.}-{0:0}, at: console_callback+0x6a/0x440 drivers/tty/vt/vt.c:2933 #3: ffff88802146c280 (&helper->lock){+.+.}-{3:3}, at: drm_fb_helper_pan_display+0xbe/0xbd0 drivers/gpu/drm/drm_fb_helper.c:1436 #4: ffff8880213381b0 (&dev->master_mutex){+.+.}-{3:3}, at: drm_master_internal_acquire+0x20/0x70 drivers/gpu/drm/drm_auth.c:458 #5: ffff88802146c098 (&client->modeset_mutex){+.+.}-{3:3}, at: drm_client_modeset_commit_locked+0x4c/0x4c0 drivers/gpu/drm/drm_client_modeset.c:1158 #6: ffffc900047af570 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0x111/0x7b0 drivers/gpu/drm/drm_client_modeset.c:996 #7: ffff88802146b0b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0x2a6/0x620 drivers/gpu/drm/drm_modeset_lock.c:314 1 lock held by syz.0.47/6029: #0: ffffffff973c9a68 (&ls_lock){+.+.}-{3:3}, at: __dlm_new_lockspace+0xb1/0x2360 fs/dlm/lockspace.c:687 1 lock held by dlm_recoverd/6036: #0: ffff88807d1d0aa8 (&ls->ls_in_recovery){+.+.}-{3:3}, at: dlm_recoverd+0xa5/0x1e50 fs/dlm/recoverd.c:310 1 lock held by syz-executor/8528: 1 lock held by syz-executor/8530: 2 locks held by syz-executor/8533: 2 locks held by syz.0.292/8785: 1 lock held by cmp/8799: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 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+0xf59/0xfa0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8530 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:__lock_acquire+0xee8/0x7d80 kernel/locking/lockdep.c:5127 Code: c7 44 24 20 00 00 00 00 eb 06 b0 01 89 44 24 20 48 8b 44 24 58 42 0f b6 04 00 84 c0 0f 85 50 0d 00 00 48 8b 44 24 18 44 8b 20 <48> 83 7d 10 00 0f 84 9d 00 00 00 48 8b 44 24 78 42 0f b6 04 00 84 RSP: 0018:ffffc90002e46560 EFLAGS: 00000046 RAX: ffff888019726550 RBX: 000000000006047a RCX: ffffffff81689802 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911eb500 RBP: ffffc90002e467a8 R08: dffffc0000000000 R09: 1ffffffff223d6a0 R10: dffffc0000000000 R11: fffffbfff223d6a1 R12: 0000000000020018 R13: ffff888019725a00 R14: ffff8880197264d0 R15: ee0f6b98b878c8ac FS: 0000555564ef0500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc9c12d0286 CR3: 0000000026a9c000 CR4: 00000000003506e0 Call Trace: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock_sched include/linux/rcupdate.h:878 [inline] pfn_valid include/linux/mmzone.h:2011 [inline] __virt_addr_valid+0x128/0x380 arch/x86/mm/physaddr.c:65 kasan_addr_to_slab+0xd/0xd0 mm/kasan/common.c:36 __kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:477 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x900 kernel/rcu/tree.c:2837 fib6_info_release include/net/ip6_fib.h:349 [inline] fixup_permanent_addr net/ipv6/addrconf.c:3596 [inline] addrconf_permanent_addr+0x3a4/0xa50 net/ipv6/addrconf.c:3624 addrconf_notify+0x996/0x1010 net/ipv6/addrconf.c:3696 notifier_call_chain+0x18f/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] __dev_notify_flags+0x1ab/0x310 net/core/dev.c:8762 dev_change_flags+0xde/0x1a0 net/core/dev.c:8800 do_setlink+0xb69/0x3f40 net/core/rtnetlink.c:2917 __rtnl_newlink net/core/rtnetlink.c:3715 [inline] rtnl_newlink+0x1848/0x2170 net/core/rtnetlink.c:3762 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7092d5e84e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffebde8e088 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555564ef0500 RCX: 00007f7092d5e84e RDX: 000000000000002c RSI: 00007f7093b54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffebde8e104 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f7093b54670 R15: 0000000000000000