INFO: task syz.3.51:6310 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-03645-g3d413f0cfd7e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.51 state:D stack:26296 pid:6310 tgid:6213 ppid:5833 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:882 [inline] lookup_slow+0x46/0x70 fs/namei.c:1833 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2639 [inline] path_lookupat+0x163/0x430 fs/namei.c:2663 filename_lookup+0x212/0x570 fs/namei.c:2692 user_path_at+0x3a/0x60 fs/namei.c:3127 do_mount fs/namespace.c:4219 [inline] __do_sys_mount fs/namespace.c:4433 [inline] __se_sys_mount+0x2d3/0x410 fs/namespace.c:4410 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: 0033:0x7f1ccfd8e969 RSP: 002b:00007f1cd0cae038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f1ccffb6080 RCX: 00007f1ccfd8e969 RDX: 0000200000000380 RSI: 0000200000000140 RDI: 0000000000000000 RBP: 00007f1ccfe10ab1 R08: 00002000000003c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1ccffb6080 R15: 00007ffc9c744978 INFO: task syz.3.51:6313 blocked for more than 144 seconds. Not tainted 6.15.0-syzkaller-03645-g3d413f0cfd7e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.51 state:D stack:28936 pid:6313 tgid:6213 ppid:5833 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:882 [inline] open_last_lookups fs/namei.c:3806 [inline] path_openat+0x8cb/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 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/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1ccfd8e969 RSP: 002b:00007f1cd0c8d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1ccffb6160 RCX: 00007f1ccfd8e969 RDX: 0000000000000000 RSI: 0000200000000000 RDI: ffffffffffffff9c RBP: 00007f1ccfe10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000021 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f1ccffb6160 R15: 00007ffc9c744978 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3ccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 4 locks held by kworker/u8:5/1149: #0: ffff88801faca148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801faca148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90003e8fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003e8fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff88805030a0e0 (&type->s_umount_key#99){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88807a5bafe0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 2 locks held by kworker/u8:7/3024: 2 locks held by getty/5580: #0: ffff88814bf940a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by udevd/5819: #0: ffff8880b8839dd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8823f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 4 locks held by syz.3.51/6214: 1 lock held by syz.3.51/6310: #0: ffff88807a5bb390 (&type->i_mutex_dir_key#15){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:882 [inline] #0: ffff88807a5bb390 (&type->i_mutex_dir_key#15){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 1 lock held by syz.3.51/6313: #0: ffff88807a5bb390 (&type->i_mutex_dir_key#15){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:882 [inline] #0: ffff88807a5bb390 (&type->i_mutex_dir_key#15){++++}-{4:4}, at: open_last_lookups fs/namei.c:3806 [inline] #0: ffff88807a5bb390 (&type->i_mutex_dir_key#15){++++}-{4:4}, at: path_openat+0x8cb/0x3830 fs/namei.c:4043 3 locks held by syz.8.264/8296: 1 lock held by dhcpcd-run-hook/8299: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-03645-g3d413f0cfd7e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 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: 8296 Comm: syz.8.264 Not tainted 6.15.0-syzkaller-03645-g3d413f0cfd7e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:match_held_lock+0x0/0xc0 kernel/locking/lockdep.c:5308 Code: 41 5e 41 5f e9 01 cb 02 00 cc e8 fb f8 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 56 53 bb 01 00 00 00 48 39 77 10 74 6a 81 7f 20 00 00 20 00 72 RSP: 0018:ffffc90015b276d0 EFLAGS: 00000083 RAX: 0000000000000002 RBX: ffff888030590b18 RCX: 6db879fdfcea5400 RDX: 0000000000000000 RSI: ffffffff8df3cd20 RDI: ffff888030590b18 RBP: 00000000ffffffff R08: ffffffff8f7ec6a7 R09: 1ffffffff1efd8d4 R10: dffffc0000000000 R11: fffffbfff1efd8d5 R12: 0000000000000246 R13: ffff888030590000 R14: ffffffff8df3cd20 R15: 0000000000000001 FS: 00007f15a855a6c0(0000) GS:ffff8881261c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b3b7f88950 CR3: 0000000053800000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:5604 [inline] lock_is_held_type+0xa8/0x190 kernel/locking/lockdep.c:5943 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0xa6/0x610 kernel/sched/core.c:8757 shmem_inode_acct_blocks+0x113/0x470 mm/shmem.c:231 shmem_alloc_and_add_folio+0x8bc/0xf60 mm/shmem.c:1919 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2529 shmem_get_folio mm/shmem.c:2635 [inline] shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3285 generic_perform_write+0x2c7/0x910 mm/filemap.c:4103 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3460 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 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: 0033:0x7f15a778d41f 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:00007f15a8559df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f15a778d41f RDX: 0000000001000000 RSI: 00007f159d000000 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000591b R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000005 R13: 00007f15a8559ef0 R14: 00007f15a8559eb0 R15: 00007f159d000000