INFO: task syz.0.868:13336 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.868 state:D stack:26688 pid:13336 tgid:13334 ppid:11130 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
user_get_super+0xc8/0x120 fs/super.c:1001
quotactl_block fs/quota/quota.c:889 [inline]
__do_sys_quotactl fs/quota/quota.c:955 [inline]
__se_sys_quotactl+0x540/0x9e0 fs/quota/quota.c:917
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: 0033:0x7fe11dfbc819
RSP: 002b:00007fe11c20e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fe11e235fa0 RCX: 00007fe11dfbc819
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: ffffffff80000901
RBP: 00007fe11e052c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe11e236038 R14: 00007fe11e235fa0 R15: 00007ffe05ebd128
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88803f612938 ((wq_completion)loop8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88803f612938 ((wq_completion)loop8){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90000127c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90000127c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88802528e160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff88802528e160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953
1 lock held by khungtaskd/37:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5557:
#0: ffff88823bf200a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5791:
#0: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#0: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
3 locks held by udevd/5804:
#0: ffff88803724c480 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline]
#0: ffff88803724c480 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#1: ffff888061b40c38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff888061b40c38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: shmem_file_write_iter+0x82/0x120 mm/shmem.c:3492
#2: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
3 locks held by syz-executor/5810:
3 locks held by udevd/5814:
#0: ffff88803724c480 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline]
#0: ffff88803724c480 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#1: ffff88802959cd38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff88802959cd38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: shmem_file_write_iter+0x82/0x120 mm/shmem.c:3492
#2: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
6 locks held by udevd/5816:
#0: ffff888022781670 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff888022781670 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
#1: ffff888034025eb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline]
#1: ffff888034025eb0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline]
#1: ffff888034025eb0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501
#2: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#2: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#2: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#3: ffff88802b0704d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff88802b0704d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#4: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#4: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#4: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#4: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#5: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#5: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
1 lock held by syz-executor/13252:
#0: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#0: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: lru_add_drain+0x136/0x3f0 mm/swap.c:736
1 lock held by syz.0.868/13336:
#0: ffff8880402d60d0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880402d60d0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.6.1066/15009:
#0: ffff8880402d60d0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880402d60d0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
3 locks held by syz.8.1077/15140:
#0: ffff88803511e588 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff8880203665f8 (sb_pagefaults#6){.+.+}-{0:0}, at: xfs_write_fault+0x2b2/0x660 fs/xfs/xfs_file.c:1932
#2: ffff888060eb62e0 (mapping.invalidate_lock#4){++++}-{4:4}, at: xfs_ilock+0x1a6/0x3b0 fs/xfs/xfs_inode.c:160
5 locks held by syz.8.1077/15145:
2 locks held by syz.3.1081/15159:
5 locks held by syz.9.1082/15179:
#0: ffff88805ce941c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#2: ffff88804be23118 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff88804be23118 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
5 locks held by dhcpcd-run-hook/15181:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15182 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:list_empty include/linux/list.h:381 [inline]
RIP: 0010:waitqueue_active include/linux/wait.h:127 [inline]
RIP: 0010:get_page_from_freelist+0x41c/0x2950 mm/page_alloc.c:3888
Code: 03 42 80 3c 00 00 74 17 48 89 df e8 ee 15 0e 00 48 8b 74 24 18 49 b8 00 00 00 00 00 fc ff df 48 8b 1b b8 48 51 00 00 48 01 c3 <48> 89 d8 48 c1 e8 03 42 80 3c 00 00 74 17 48 89 df e8 be 15 0e 00
RSP: 0000:ffffc9000d947808 EFLAGS: 00000286
RAX: 0000000000005148 RBX: ffff888140000888 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffff88813fffdf50 RDI: ffff88813fffdf50
RBP: 0000000000000000 R08: dffffc0000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1027fff9d1 R12: ffff88813fffcd78
R13: 0000000000000981 R14: 0000000000000000 R15: ffffc9000d947a3c
FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f75da48c050 CR3: 0000000050198000 CR4: 00000000003526f0
Call Trace:
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2490
folio_alloc_mpol_noprof mm/mempolicy.c:2509 [inline]
vma_alloc_folio_noprof+0xea/0x290 mm/mempolicy.c:2544
folio_prealloc mm/memory.c:-1 [inline]
do_cow_fault mm/memory.c:5823 [inline]
do_fault mm/memory.c:5935 [inline]
do_pte_missing+0x545/0x29e0 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6624
do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f75da318494
Code: 48 39 d8 73 2d 90 48 8b 30 8b 50 08 48 01 ee 48 83 fa 26 74 0a 48 83 fa 08 0f 85 04 0c 00 00 48 8b 50 10 48 83 c0 18 48 01 ea <48> 89 16 48 39 d8 72 d4 4d 8b 95 08 02 00 00 4d 85 d2 0f 84 b4 04
RSP: 002b:00007fff5f1d3470 EFLAGS: 00010206
RAX: 00007f75da180e48 RBX: 00007f75da1ba670 RCX: 00007f75da1703b8
RDX: 00007f75da384a88 RSI: 00007f75da48c050 RDI: 00007f75da1ba670
RBP: 00007f75da170000 R08: 00007f75da1baa78 R09: 00007f75da1703d8
R10: 00000000effffef5 R11: 00007f75da55d8a0 R12: 00007fff5f1d34b0
R13: 00007f75da55d8a0 R14: 0000000000000000 R15: 00007f75da1baa78