INFO: task syz.0.15:5057 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.15 state:D stack:25192 pid: 5057 ppid: 4779 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] pickup_page_for_submission fs/erofs/zdata.c:1135 [inline] z_erofs_submit_queue fs/erofs/zdata.c:1306 [inline] z_erofs_runqueue+0x6bf/0x1890 fs/erofs/zdata.c:1367 z_erofs_readahead+0xb81/0x10c0 fs/erofs/zdata.c:1459 read_pages+0x165/0x920 mm/readahead.c:130 page_cache_ra_unbounded+0x830/0x930 mm/readahead.c:239 do_page_cache_ra mm/readahead.c:269 [inline] force_page_cache_ra+0x3e5/0x440 mm/readahead.c:301 force_page_cache_readahead mm/internal.h:78 [inline] generic_fadvise+0x520/0x7d0 mm/fadvise.c:107 vfs_fadvise mm/fadvise.c:186 [inline] ksys_fadvise64_64 mm/fadvise.c:200 [inline] __do_sys_fadvise64 mm/fadvise.c:215 [inline] __se_sys_fadvise64 mm/fadvise.c:213 [inline] __x64_sys_fadvise64+0x139/0x180 mm/fadvise.c:213 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f1025aacef9 RSP: 002b:00007f1024d2d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000dd RAX: ffffffffffffffda RBX: 00007f1025c64f80 RCX: 00007f1025aacef9 RDX: 0000000000004101 RSI: 0000000000e0ffff RDI: 0000000000000004 RBP: 00007f1025b1fb76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1025c64f80 R15: 00007fff03d97b48 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by udevd/3561: 2 locks held by getty/3952: #0: ffff88814cfbf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/0:14/4251: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000348fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88801fb3e240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480 1 lock held by syz.0.15/5057: #0: ffff88805c8ec320 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:842 [inline] #0: ffff88805c8ec320 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x190/0x930 mm/readahead.c:195 1 lock held by udevd/6283: 2 locks held by syz.0.5518/16531: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4684 Comm: kworker/1:21 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: rcu_gp process_srcu RIP: 0010:preempt_count_add+0x2/0x190 kernel/sched/core.c:5499 Code: e1 07 80 c1 03 38 c1 7c 97 48 8b 3c 24 e8 16 c4 6a 00 eb 8c e9 f5 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 <41> 56 53 49 bf 00 00 00 00 00 fc ff df 48 c7 c0 80 0f 0b 96 48 c1 RSP: 0018:ffffc9000314fab0 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 0000000000002af9 RCX: 0000000000000000 RDX: 0000000000000087 RSI: ffffffff8a59e7e0 RDI: 0000000000000001 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffff52000629f25 R10: fffff52000629f25 R11: 1ffff92000629f24 R12: dffffc0000000000 R13: ffffffff9611b800 R14: 000000870426a14a R15: 00000000000009b4 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3362928fd2 CR3: 00000000223e7000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: delay_tsc+0x61/0xc0 arch/x86/lib/delay.c:79 try_check_zero+0x2c7/0x340 kernel/rcu/srcutree.c:702 srcu_advance_state kernel/rcu/srcutree.c:1227 [inline] process_srcu+0x195/0xc10 kernel/rcu/srcutree.c:1325 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287