INFO: task syz.2.1260:19057 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1260 state:D stack:24776 pid:19057 tgid:19056 ppid:5813 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
kthread_flush_worker+0x1c6/0x240 kernel/kthread.c:1564
__alloc_workqueue+0x1470/0x1b70 kernel/workqueue.c:5795
alloc_workqueue_noprof+0xd4/0x210 kernel/workqueue.c:5818
xfs_pwork_init+0x110/0x3e0 fs/xfs/xfs_pwork.c:74
xfs_iwalk_threaded+0x110/0x580 fs/xfs/xfs_iwalk.c:652
xfs_qm_quotacheck+0x2b1/0x6e0 fs/xfs/xfs_qm.c:1547
xfs_qm_mount_quotas+0x26a/0x670 fs/xfs/xfs_qm.c:1689
xfs_mountfs+0x1af2/0x22c0 fs/xfs/xfs_mount.c:1187
xfs_fs_fill_super+0x1185/0x15d0 fs/xfs/xfs_super.c:1926
get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1692
vfs_get_tree+0x8f/0x2b0 fs/super.c:1752
do_new_mount+0x2a2/0xa30 fs/namespace.c:3750
do_mount fs/namespace.c:4078 [inline]
__do_sys_mount fs/namespace.c:4278 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4255
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdff60d066a
RSP: 002b:00007fdff432de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fdff432def0 RCX: 00007fdff60d066a
RDX: 0000200000009700 RSI: 0000200000009740 RDI: 00007fdff432deb0
RBP: 0000200000009700 R08: 00007fdff432def0 R09: 0000000004000000
R10: 0000000004000000 R11: 0000000000000246 R12: 0000200000009740
R13: 00007fdff432deb0 R14: 000000000000975c R15: 00002000000000c0
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d3a9b40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d3a9b40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d3a9b40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:2/43:
2 locks held by dhcpcd/5475:
#0: ffff8880657ae910 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269
#1: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814
2 locks held by getty/5570:
#0: ffff88823bf240a0 (&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+0x444/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/5809:
1 lock held by syz-executor/5815:
#0: ffff888031a5a0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff888031a5a0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff888031a5a0d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
3 locks held by kworker/1:7/5897:
#0: ffff888019498938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888019498938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000598fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000598fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/u8:13/7732:
#0: ffff888019481138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888019481138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000ca9fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000ca9fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
4 locks held by kworker/u8:4/18873:
#0: ffff88801a2ec138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801a2ec138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9001f887bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9001f887bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e65b060 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669
#3: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#3: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990 net/core/net_namespace.c:248
1 lock held by syz.2.1260/19057:
#0: ffff88802ca9e0d0 (&type->s_umount_key#57/1){+.+.}-{4:4}, at: alloc_super+0x204/0x990 fs/super.c:345
2 locks held by syz-executor/20826:
#0: ffffffff8ddd0ce0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ddd0ce0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ddd0ce0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e667fb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
2 locks held by syz.4.1511/21020:
4 locks held by syz.5.1512/21031:
#0: ffff88803c8851c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x19f/0x3d0 mm/mmap_lock.c:147
#1: ffff88814e130600 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x14d/0x310 mm/memory.c:3361
#2: ffff88805c898f00 (&ei->i_mmap_lock){++++}-{4:4}, at: btrfs_page_mkwrite+0x608/0x1a80 fs/btrfs/file.c:1919
#3: ffff88805c898c00 (&tree->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#3: ffff88805c898c00 (&tree->lock){+.+.}-{3:3}, at: wait_extent_bit fs/btrfs/extent-io-tree.c:815 [inline]
#3: ffff88805c898c00 (&tree->lock){+.+.}-{3:3}, at: btrfs_lock_extent_bits+0x58f/0x6e0 fs/btrfs/extent-io-tree.c:1917
6 locks held by syz.6.1514/21037:
1 lock held by udevadm/21054:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
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: 21037 Comm: syz.6.1514 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1169 [inline]
RIP: 0010:unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
Code: 00 e8 32 30 32 00 4c 8d 3d 00 00 00 00 48 c7 c7 40 9b 3a 8d 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 1e 5d 28 00 <48> 83 c4 08 e8 85 64 43 09 85 c0 74 3a e8 ac 75 31 00 84 c0 75 31
RSP: 0018:ffffc9001d017170 EFLAGS: 00000282
RAX: 8ad46d30a8ba0200 RBX: ffffffff81a99d9c RCX: 8ad46d30a8ba0200
RDX: 0000000000000000 RSI: ffffffff8cd9009a RDI: ffffffff8b1d9760
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81724cd5
R10: ffffc9001d017298 R11: ffffffff81a99df0 R12: 1ffff92003a02e49
R13: ffffc9001d017280 R14: ffffc9001d017248 R15: ffffffff81724cd5
FS: 00007f2d7fe666c0(0000) GS:ffff888127117000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0ee46dd58 CR3: 000000006f40a000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:156
__set_page_owner+0x8d/0x490 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x26dc/0x2770 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
folio_alloc_mpol_noprof+0x39/0xe0 mm/mempolicy.c:2435
shmem_alloc_folio mm/shmem.c:1908 [inline]
shmem_alloc_and_add_folio mm/shmem.c:1947 [inline]
shmem_get_folio_gfp+0x633/0x1a70 mm/shmem.c:2597
shmem_get_folio mm/shmem.c:2703 [inline]
shmem_write_begin+0xef/0x2a0 mm/shmem.c:3353
generic_perform_write+0x29a/0x8c0 mm/filemap.c:4175
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3528
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5d2/0xb40 fs/read_write.c:686
ksys_write+0x14b/0x260 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d81bfd97f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f2d7fe65df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f2d81bfd97f
RDX: 0000000001000000 RSI: 00007f2d77a46000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005597
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f2d7fe65ef0 R14: 00007f2d7fe65eb0 R15: 00007f2d77a46000