INFO: task kworker/u8:26:9430 blocked for more than 143 seconds.
Tainted: G U 6.15.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:26 state:D stack:24680 pid:9430 tgid:9430 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:116
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4000
rds_tcp_listen_stop+0x104/0x150 net/rds/tcp_listen.c:351
rds_tcp_kill_sock net/rds/tcp.c:611 [inline]
rds_tcp_exit_net+0xcb/0x810 net/rds/tcp.c:634
ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172
cleanup_net+0x5c1/0xb30 net/core/net_namespace.c:654
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bfa80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bfa80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bfa80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
3 locks held by kworker/u8:26/9430:
#0: ffff88801c2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90004117d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608
2 locks held by getty/15083:
#0: ffff8880356320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900198132f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by syz.0.2068/15796:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
1 lock held by syz.3.2145/16126:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
1 lock held by syz.2.2187/16281:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
1 lock held by syz.4.2286/16732:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
1 lock held by syz.6.2513/17565:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
1 lock held by syz.5.2514/17568:
#0: ffffffff90114550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:514
2 locks held by syz.7.2523/17604:
5 locks held by syz.7.2542/17680:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U 6.15.0-rc7-syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153
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: 17680 Comm: syz.7.2542 Tainted: G U 6.15.0-rc7-syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:unwind_next_frame+0x572/0x20a0 arch/x86/kernel/unwind_orc.c:512
Code: c1 ee 03 48 c1 ea 03 0f b6 14 02 0f b6 04 06 4c 89 c6 83 e6 07 40 38 f2 40 0f 9e c6 84 d2 0f 95 c2 40 84 d6 0f 85 b8 13 00 00 <41> 83 e7 07 44 38 f8 0f 9e c2 84 c0 0f 95 c0 84 c2 0f 85 a1 13 00
RSP: 0000:ffffc9000c077068 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff9126578c
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff909f1068
RBP: ffffc9000c077120 R08: ffffffff91265790 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000011290 R12: ffffc9000c077128
R13: ffffc9000c0770d8 R14: ffffc9000c07710d R15: ffffffff91265791
FS: 00007f4b827aa6c0(0000) GS:ffff888124ae7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000018e6000 CR3: 0000000095fc6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__set_page_owner+0x91/0x550 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1714
prep_new_page mm/page_alloc.c:1722 [inline]
get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3684
__alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4966
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2301
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2320
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1854
shmem_alloc_and_add_folio+0x499/0xc20 mm/shmem.c:1893
shmem_get_folio_gfp+0x687/0x1530 mm/shmem.c:2533
shmem_fault+0x1fe/0xa30 mm/shmem.c:2734
__do_fault+0x10a/0x490 mm/memory.c:5098
do_read_fault mm/memory.c:5518 [inline]
do_fault mm/memory.c:5652 [inline]
do_pte_missing+0x1031/0x3fb0 mm/memory.c:4160
handle_pte_fault mm/memory.c:5997 [inline]
__handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309
do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337
handle_page_fault arch/x86/mm/fault.c:1480 [inline]
exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x18e6000
Code: Unable to access opcode bytes at 0x18e5fd6.
RSP: 002b:000000000000000d EFLAGS: 00010206
RAX: 0000000000000000 RBX: 00007f4b81bb5fa0 RCX: 00007f4b8198e969
RDX: ffffffffffffffff RSI: 0000000000000005 RDI: 0000000000008001
RBP: 00007f4b81a10ab1 R08: 0000000000000006 R09: 0000000000000000
R10: ffffffffff600000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4b81bb5fa0 R15: 00007ffe4b7fbab8
vkms_vblank_simulate: vblank timer overrun