INFO: task syz.0.973:9492 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.973 state:D stack:28024 pid:9492 tgid:9491 ppid:5606 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7282
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7339
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
nfsd_nl_version_get_doit+0x18c/0x7f0 fs/nfsd/nfsctl.c:1863
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0x9e1/0xb70 net/socket.c:2698
___sys_sendmsg+0x190/0x1e0 net/socket.c:2752
__sys_sendmsg+0x170/0x220 net/socket.c:2784
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5465b9cdd9
RSP: 002b:00007f5466a97028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5465e15fa0 RCX: 00007f5465b9cdd9
RDX: 000000000000c040 RSI: 00002000000008c0 RDI: 0000000000000003
RBP: 00007f5465c32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5465e16038 R14: 00007f5465e15fa0 R15: 00007ffe5f2f4998
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e54e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e54e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e7e54e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5372:
#0: ffff888039cc90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
2 locks held by syz.3.537/7766:
#0: ffffffff906b87c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec62800 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x8ec/0x12b0 fs/nfsd/nfsctl.c:1633
2 locks held by syz.0.973/9492:
#0: ffffffff906b87c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec62800 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x18c/0x7f0 fs/nfsd/nfsctl.c:1863
3 locks held by kworker/1:8/10165:
#0: ffff88813fe5b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
#1: ffffc9000558fd08 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
#2: ffff888027f53a70 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:236 [inline]
#2: ffff888027f53a70 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_damage_work+0x159/0x640 drivers/gpu/drm/drm_fb_helper.c:275
10 locks held by syz.2.1915/12446:
#0: ffff888027d850a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffff888027d85128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline]
#1: ffff888027d85128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline]
#1: ffff888027d85128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write.isra.0+0x24b/0x890 drivers/tty/tty_io.c:1081
#2: ffff888027d852c8 (&tty->termios_rwsem){++++}-{4:4}, at: class_rwsem_read_constructor include/linux/rwsem.h:259 [inline]
#2: ffff888027d852c8 (&tty->termios_rwsem){++++}-{4:4}, at: n_tty_write+0x1b8/0x11c0 drivers/tty/n_tty.c:2349
#3: ffffc9000f5ad370 (&ldata->output_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#3: ffffc9000f5ad370 (&ldata->output_lock){+.+.}-{4:4}, at: process_output_block drivers/tty/n_tty.c:513 [inline]
#3: ffffc9000f5ad370 (&ldata->output_lock){+.+.}-{4:4}, at: n_tty_write+0x56d/0x11c0 drivers/tty/n_tty.c:2366
#4: ffffffff8e7d1a60 (console_lock){+.+.}-{0:0}, at: class_console_lock_constructor include/linux/console.h:736 [inline]
#4: ffffffff8e7d1a60 (console_lock){+.+.}-{0:0}, at: do_con_write+0x158/0x4a10 drivers/tty/vt/vt.c:3289
#5: ffff888027f53a70 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_pan_display+0xd6/0xa40 drivers/gpu/drm/drm_fb_helper.c:1246
#6: ffff888027eb6128 (&dev->master_mutex){+.+.}-{4:4}, at: drm_master_internal_acquire+0x21/0x80 drivers/gpu/drm/drm_auth.c:435
#7: ffff888027f53890 (&client->modeset_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_locked+0x4c/0x580 drivers/gpu/drm/drm_client_modeset.c:1205
#8: ffffc900059cf430 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xc4/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1043
#9: ffffc900059cf458 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_atomic+0xc4/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1043
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
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: 30 Comm: kauditd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_preemption_disabled+0x1a/0xe0 lib/smp_processor_id.c:16
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d 65 b8 80 08 65 f7 05 56 b8 80 08 ff ff ff 7f <74> 0f 48 83 c4 08 89 d8 5b 5d 41 5c c3 cc cc cc cc 9c 58 f6 c4 02
RSP: 0018:ffffc90000a677d8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90000a6780c
RDX: 0000000000000000 RSI: ffffffff8def8e2e RDI: ffffffff8c1c3200
RBP: ffffffff81b7c1ae R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 00000000000104f3 R12: ffff88801eadca00
R13: ffffc90000a678b8 R14: 0000000000000202 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124379000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc1111ea4c0 CR3: 000000005b7a8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_release kernel/locking/lockdep.c:5891 [inline]
lock_release+0x170/0x310 kernel/locking/lockdep.c:5875
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
unwind_next_frame+0x3c3/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6246 [inline]
kmem_cache_free+0x127/0x6c0 mm/slub.c:6373
kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1137
__kfree_skb net/core/skbuff.c:1204 [inline]
sk_skb_reason_drop+0x10f/0x1b0 net/core/skbuff.c:1241
kfree_skb_reason include/linux/skbuff.h:1322 [inline]
kfree_skb include/linux/skbuff.h:1331 [inline]
kauditd_hold_skb+0x144/0x210 kernel/audit.c:652
kauditd_send_queue+0x232/0x2e0 kernel/audit.c:807
kauditd_thread+0x645/0xb30 kernel/audit.c:931
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245