INFO: task syz.0.15:5253 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: 5253 ppid: 4988 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: 0033:0x7f39e2f3bef9 RSP: 002b:00007f39e21bc038 EFLAGS: 00000246 ORIG_RAX: 00000000000000dd RAX: ffffffffffffffda RBX: 00007f39e30f3f80 RCX: 00007f39e2f3bef9 RDX: 0000000000004101 RSI: 0000000000e0ffff RDI: 0000000000000004 RBP: 00007f39e2faeb76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f39e30f3f80 R15: 00007fff0e4a46f8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by udevd/3561: 2 locks held by getty/3944: #0: ffff88814cd32098 (&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 2 locks held by kworker/0:8/4260: 1 lock held by syz.0.15/5253: #0: ffff888068d80320 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:842 [inline] #0: ffff888068d80320 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x190/0x930 mm/readahead.c:195 1 lock held by syz-executor/16480: ============================================= 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 08/18/2025 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3561 Comm: udevd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:check_preemption_disabled+0x56/0x110 lib/smp_processor_id.c:19 Code: 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 74 cc 65 4c 8b 3d b6 30 59 76 41 f6 RSP: 0018:ffffc90002ddfba0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a4c0 RBP: ffffc90002ddfcf0 R08: dffffc0000000000 R09: fffffbfff1ff7a1b R10: fffffbfff1ff7a1b R11: 1ffffffff1ff7a1a R12: ffffffff8c1ecd60 R13: 1ffff920005bbf88 R14: 0000000000000246 R15: dffffc0000000000 FS: 00007f368df02880(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31b5ffff CR3: 000000002a26f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:436 [inline] lock_acquire+0x1a7/0x3f0 kernel/locking/lockdep.c:5625 fs_reclaim_acquire+0x91/0x100 mm/page_alloc.c:4597 might_alloc include/linux/sched/mm.h:206 [inline] slab_pre_alloc_hook+0x20/0xc0 mm/slab.h:492 slab_alloc_node mm/slub.c:3139 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x3d/0x290 mm/slub.c:3238 getname_flags+0xb5/0x500 fs/namei.c:138 user_path_at_empty+0x2a/0x190 fs/namei.c:2882 do_readlinkat+0xd4/0x480 fs/stat.c:442 __do_sys_readlink fs/stat.c:475 [inline] __se_sys_readlink fs/stat.c:472 [inline] __x64_sys_readlink+0x7b/0x90 fs/stat.c:472 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: 0033:0x7f368e05e3a7 Code: 00 00 90 48 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 00 31 c9 e8 8a 20 f9 ff 48 83 c4 18 c3 0f 1f 44 00 00 b8 59 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 21 ba 0d 00 f7 d8 64 89 02 48 RSP: 002b:00007ffef915e158 EFLAGS: 00000202 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007ffef915e360 RCX: 00007f368e05e3a7 RDX: 0000000000000200 RSI: 00007ffef915e160 RDI: 00007ffef915e360 RBP: 000055d87d72c910 R08: 0000000000000064 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffef915e160 R13: 000055d857fa7100 R14: 0000000000000001 R15: 00007ffef915e980