INFO: task syz.4.2139:14680 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2139 state:D stack:26096 pid:14680 ppid:13890 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 io_schedule+0x7c/0xd0 kernel/sched/core.c:8798 folio_wait_bit_common+0x70a/0xfa0 mm/filemap.c:1324 lock_page include/linux/pagemap.h:997 [inline] pickup_page_for_submission fs/erofs/zdata.c:1330 [inline] z_erofs_submit_queue fs/erofs/zdata.c:1522 [inline] z_erofs_runqueue+0x8fe/0x1c60 fs/erofs/zdata.c:1594 z_erofs_readahead+0xa55/0xdd0 fs/erofs/zdata.c:1733 read_pages+0x185/0x850 mm/readahead.c:161 page_cache_ra_unbounded+0x690/0x770 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra+0x2bd/0x320 mm/readahead.c:331 force_page_cache_readahead mm/internal.h:125 [inline] generic_fadvise+0x47a/0x720 mm/fadvise.c:107 vfs_fadvise mm/fadvise.c:185 [inline] ksys_fadvise64_64 mm/fadvise.c:199 [inline] __do_sys_fadvise64 mm/fadvise.c:214 [inline] __se_sys_fadvise64 mm/fadvise.c:212 [inline] __x64_sys_fadvise64+0x139/0x180 mm/fadvise.c:212 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f857c39c819 RSP: 002b:00007f857d1df028 EFLAGS: 00000246 ORIG_RAX: 00000000000000dd RAX: ffffffffffffffda RBX: 00007f857c615fa0 RCX: 00007f857c39c819 RDX: 000000000000a93d RSI: 000000000000fff8 RDI: 0000000000000004 RBP: 00007f857c432c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f857c616038 R14: 00007f857c615fa0 R15: 00007ffd815d4eb8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df30 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2e750 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4028: #0: ffff88814d08b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198 6 locks held by kworker/1:6/4314: 1 lock held by syz.4.2139/14680: #0: ffff8880547dc358 (mapping.invalidate_lock#8){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:813 [inline] #0: ffff8880547dc358 (mapping.invalidate_lock#8){.+.+}-{3:3}, at: page_cache_ra_unbounded+0xd8/0x770 mm/readahead.c:226 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4319 Comm: kworker/u4:6 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bat_events batadv_nc_worker RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212 Code: 2e 0f 1f 84 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 90 6c 9d 0c 48 89 de 5b e9 97 41 50 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d a4 fa 7f 7e 65 8b 15 a5 fa 7f 7e 81 e2 00 RSP: 0018:ffffc900040a7bd8 EFLAGS: 00000283 RAX: 0000000000000400 RBX: ffff888057ac85c0 RCX: 61be426bb2736500 RDX: 0000000000000002 RSI: ffffffff8a8c2220 RDI: ffffffff8adf0d20 RBP: fffffffffffffe38 R08: ffffffff8e1fdeef R09: 1ffffffff1c3fbdd R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: dffffc0000000000 R13: ffff888057ac85d0 R14: ffff888057a9cc80 R15: 0000000000000013 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff59da47000 CR3: 000000000c88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:405 [inline] batadv_nc_worker+0x2b1/0x600 net/batman-adv/network-coding.c:719 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295