INFO: task syz.1.112:6597 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.112 state:D stack:24488 pid:6597 tgid:6596 ppid:5807 task_flags:0x400140 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] 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 f2fs_issue_checkpoint+0x382/0x610 fs/f2fs/checkpoint.c:-1 f2fs_do_sync_file+0x86c/0x1860 fs/f2fs/file.c:352 generic_write_sync include/linux/fs.h:3046 [inline] f2fs_file_write_iter+0x756/0x2480 fs/f2fs/file.c:5266 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5d5/0xb40 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/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7ba63cefc9 RSP: 002b:00007f7ba462e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7ba6625fa0 RCX: 00007f7ba63cefc9 RDX: 000000000000ffd3 RSI: 0000200000000140 RDI: 0000000000000008 RBP: 00007f7ba6451f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7ba6626038 R14: 00007f7ba6625fa0 R15: 00007fffbb465338 INFO: task syz.1.112:6626 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.112 state:D stack:29048 pid:6626 tgid:6596 ppid:5807 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+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 fdget_pos+0x253/0x320 fs/file.c:1232 class_fd_pos_constructor include/linux/file.h:85 [inline] ksys_read+0x79/0x260 fs/read_write.c:706 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: 0033:0x7f7ba63cefc9 RSP: 002b:00007f7ba460d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f7ba6626090 RCX: 00007f7ba63cefc9 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007f7ba6451f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7ba6626128 R14: 00007f7ba6626090 R15: 00007fffbb465338 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/43: #0: ffff88801eaa2938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801eaa2938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90000b47ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90000b47ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff88803c1300d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562 5 locks held by kworker/u8:3/58: 2 locks held by dhcpcd/5463: #0: ffff88804fb70920 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269 #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6819 2 locks held by getty/5560: #0: ffff88823bf5a8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222 2 locks held by kworker/0:7/5889: 2 locks held by syz.1.112/6597: #0: ffff88803e441f28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x253/0x320 fs/file.c:1232 #1: ffff88803c130480 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline] #1: ffff88803c130480 (sb_writers#14){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 1 lock held by syz.1.112/6626: #0: ffff88803e441f28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x253/0x320 fs/file.c:1232 3 locks held by f2fs_ckpt-7:1/6612: 1 lock held by syz-executor/6765: 13 locks held by kworker/u8:12/7185: 2 locks held by syz-executor/7730: #0: ffffffff8ed64450 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed64450 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8ed64450 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064 2 locks held by syz-executor/7907: #0: ffffffff8ed64578 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed64578 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8ed64578 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8e862e38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064 2 locks held by syz.2.359/8048: 3 locks held by syz.4.360/8047: 1 lock held by udevadm/8050: ============================================= NMI backtrace for cpu 1 CPU: 1 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6612 Comm: f2fs_ckpt-7:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:kasan_check_range+0x9/0x2c0 mm/kasan/generic.c:199 Code: 0b 90 b8 ea ff ff ff eb e1 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 41 57 41 56 <41> 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 RSP: 0018:ffffc9000dfcf3e0 EFLAGS: 00000046 RAX: 1ffff1100bca8e58 RBX: ffff88805e5472c0 RCX: ffffffff8ac30ae0 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88805e5472d0 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52001bf9eb8 R12: 0000000000000000 R13: ffff88805e5472d0 R14: ffff88805e547280 R15: ffff8880334f5a00 FS: 0000000000000000(0000) GS:ffff888126dfc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcdebc29b60 CR3: 000000001efce000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] rt_mutex_set_owner kernel/locking/rtmutex.c:113 [inline] try_to_take_rt_mutex+0x840/0xb00 kernel/locking/rtmutex.c:1191 rtlock_slowlock_locked+0xd8/0x4010 kernel/locking/rtmutex.c:1839 rtlock_slowlock kernel/locking/rtmutex.c:1895 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x158/0x3e0 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:44 [inline] igrab+0x21/0xb0 fs/inode.c:1547 f2fs_sync_inode_meta fs/f2fs/checkpoint.c:1149 [inline] block_operations fs/f2fs/checkpoint.c:1263 [inline] f2fs_write_checkpoint+0xad2/0x2440 fs/f2fs/checkpoint.c:1678 __write_checkpoint_sync fs/f2fs/checkpoint.c:1802 [inline] __checkpoint_and_complete_reqs+0xdf/0x3d0 fs/f2fs/checkpoint.c:1821 issue_checkpoint_thread+0xd9/0x260 fs/f2fs/checkpoint.c:1853 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