INFO: task syz.1.396:8785 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.396 state:D stack:29224 pid:8785 tgid:8773 ppid:5811 task_flags:0x400040 flags:0x00080002
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]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1025 [inline]
filename_create+0x1f8/0x3c0 fs/namei.c:4226
do_mknodat+0x184/0x4d0 fs/namei.c:4359
__do_sys_mknod fs/namei.c:4405 [inline]
__se_sys_mknod fs/namei.c:4403 [inline]
__x64_sys_mknod+0x8c/0xa0 fs/namei.c:4403
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81e3f0efc9
RSP: 002b:00007f81e2155038 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f81e4166090 RCX: 00007f81e3f0efc9
RDX: 0000000000000703 RSI: 0000000000000200 RDI: 00002000000003c0
RBP: 00007f81e3f91f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f81e4166128 R14: 00007f81e4166090 R15: 00007ffd2d7b4a48
INFO: task syz.1.396:8786 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.396 state:D stack:29224 pid:8786 tgid:8773 ppid:5811 task_flags:0x400040 flags:0x00080002
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]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1025 [inline]
filename_create+0x1f8/0x3c0 fs/namei.c:4226
do_mkdirat+0xa0/0x590 fs/namei.c:4478
__do_sys_mkdirat fs/namei.c:4503 [inline]
__se_sys_mkdirat fs/namei.c:4501 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81e3f0d717
RSP: 002b:00007f81e2133e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f81e2133ef0 RCX: 00007f81e3f0d717
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 0000200000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007f81e2133eb0 R14: 0000000000000000 R15: 00002000000001c0
INFO: task syz.1.396:8787 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.396 state:D stack:28648 pid:8787 tgid:8773 ppid:5811 task_flags:0x400040 flags:0x00080002
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]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock include/linux/fs.h:980 [inline]
open_last_lookups fs/namei.c:3892 [inline]
path_openat+0x8e6/0x3840 fs/namei.c:4131
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81e3f0efc9
RSP: 002b:00007f81e1d11038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f81e4166270 RCX: 00007f81e3f0efc9
RDX: 000000000000275a RSI: 0000200000000280 RDI: ffffffffffffff9c
RBP: 00007f81e3f91f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f81e4166308 R14: 00007f81e4166270 R15: 00007ffd2d7b4a48
Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
#0: ffff88801c2bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801c2bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc90000117ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc90000117ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff8880377760d0 (&type->s_umount_key#80){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff88804a62c628 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by khungtaskd/38:
#0: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/u8:8/3524:
2 locks held by getty/5555:
#0: ffff88823bf560a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
4 locks held by udevd/5850:
#0: ffff888148dc88a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:995 [inline]
#0: ffff888148dc88a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:858
#1: ffff888148dc8a78 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline]
#1: ffff888148dc8a78 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_unbounded+0x1a3/0x8e0 mm/readahead.c:233
#2: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#2: ffffffff8d5aa6c0 (rcu_read_lock){....}-{1:3}, at: blk_mq_dispatch_queue_requests+0x552/0x800 block/blk-mq.c:2887
#3: ffff888024a73160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:93 [inline]
#3: ffff888024a73160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_work drivers/block/loop.c:805 [inline]
#3: ffff888024a73160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_rq+0x23c/0xb00 drivers/block/loop.c:1891
1 lock held by udevd/6037:
3 locks held by kworker/u8:11/7266:
#0: ffff888022e72938 ((wq_completion)loop5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888022e72938 ((wq_completion)loop5){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc90006e9fba0 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc90006e9fba0 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff888024a73160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:93 [inline]
#2: ffff888024a73160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0xf8/0x1060 drivers/block/loop.c:1951
2 locks held by kworker/u8:12/7751:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000671fba0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000671fba0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
4 locks held by syz.1.396/8774:
2 locks held by syz.1.396/8785:
#0: ffff888037776480 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
2 locks held by syz.1.396/8786:
#0: ffff888037776480 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
2 locks held by syz.1.396/8787:
#0: ffff888037776480 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: open_last_lookups fs/namei.c:3892 [inline]
#1: ffff88804a62c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: path_openat+0x8e6/0x3840 fs/namei.c:4131
4 locks held by syz.0.670/10498:
6 locks held by syz.5.673/10511:
1 lock held by syz.8.674/10513:
3 locks held by syz.6.675/10517:
1 lock held by syz.3.676/10524:
=============================================
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 10/02/2025
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:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
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: 10513 Comm: syz.8.674 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:shmem_getattr+0x87/0x4b0 mm/shmem.c:1245
Code: 74 08 4c 89 f7 e8 f9 7b 20 00 48 89 5c 24 08 49 8b 1e 4c 8d b3 f0 fd ff ff 4c 89 f0 48 c1 e8 03 48 89 44 24 28 42 80 3c 20 00 <74> 08 4c 89 f7 e8 cf 7b 20 00 4c 89 74 24 20 4c 8b ab f0 fd ff ff
RSP: 0018:ffffc90004216e28 EFLAGS: 00000246
RAX: 1ffff11007ab4d46 RBX: ffff88803d5a6c40 RCX: 0000000000080000
RDX: ffffc9001c620000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffff88803484e6c0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90004216f20 R11: ffffffff81fffb50 R12: dffffc0000000000
R13: ffffffff8d6fe900 R14: ffff88803d5a6a30 R15: ffffc90004216f20
FS: 00007f1a545c66c0(0000) GS:ffff888126ef9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda5f4e4000 CR3: 000000006d172000 CR4: 00000000003526f0
Call Trace:
vfs_getattr_nosec+0x2e1/0x430 fs/stat.c:213
loop_query_min_dio_size drivers/block/loop.c:465 [inline]
loop_assign_backing_file+0x22e/0x410 drivers/block/loop.c:518
loop_configure+0x862/0xe60 drivers/block/loop.c:1061
lo_ioctl+0x80c/0x1c70 drivers/block/loop.c:-1
blkdev_ioctl+0x5b2/0x6d0 block/ioctl.c:705
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a5635ebcb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f1a545c5dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f1a5635ebcb
RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005535
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f1a545c5ef0 R14: 00007f1a545c5eb0 R15: 00007f1a4c1a6000