INFO: task syz.1.2362:13784 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2362 state:D stack:24776 pid:13784 ppid:5781 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747 sync_bdevs+0x1af/0x330 block/bdev.c:1076 ksys_sync+0xc6/0x170 fs/sync.c:105 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3ea739aeb9 RSP: 002b:00007f3ea81c6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f3ea7615fa0 RCX: 00007f3ea739aeb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f3ea7615fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3ea7616038 R14: 00007f3ea7615fa0 R15: 00007ffcdc0d52b8 Showing all locks held in the system: 3 locks held by kworker/0:1/9: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #1: ffffc900000e7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900000e7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #2: ffff88814b569240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x286/0x31b0 drivers/net/netdevsim/fib.c:1491 1 lock held by khungtaskd/29: #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5535: #0: ffff8880317aa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 1 lock held by udevd/5776: #0: ffff888021d4d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 1 lock held by udevd/5780: #0: ffff888021ddb4c8 (&disk->open_mutex){+.+.}-{3:3} , at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 3 locks held by udevd/6150: #0: ffff888148c82a30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:814 [inline] #0: ffff888148c82a30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: blkdev_read_iter+0x32f/0x480 block/fops.c:743 #1: ffff8880b8f3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #2: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #2: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2176/0x45a0 kernel/sched/core.c:6695 1 lock held by syz.1.2362/13784: #0: ffff888021ddb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076 1 lock held by syz.9.3003/16723: #0: ffff88807eb340e0 (&type->s_umount_key#73/1){+.+.}-{3:3}, at: alloc_super+0x1fa/0x920 fs/super.c:352 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 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+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16749 Comm: rm Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x81/0x120 kernel/kcov.c:349 Code: 00 00 00 b9 01 00 00 00 48 85 c0 0f 84 ae 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 05 64 9d 7c 7e 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 52 9d 7c 7e 41 RSP: 0018:ffffc90003f66c50 EFLAGS: 00000293 RAX: 0000000000000002 RBX: ffffffff8f1d20ee RCX: 0000000000000003 RDX: ffffffff813b3c75 RSI: ffffffff8cfa0740 RDI: 0000000000000002 RBP: ffffc90003f66d98 R08: ffff88802cb59e00 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90003f66d48 R13: dffffc0000000000 R14: 0000000000000002 R15: ffffffff8f1d20f3 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055693e900950 CR3: 000000002faa6000 CR4: 00000000003506e0 Call Trace: unwind_next_frame+0x655/0x2970 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 save_stack+0x125/0x230 mm/page_owner.c:128 __set_page_owner+0x1d/0x60 mm/page_owner.c:192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3191 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x1b3/0x2d0 mm/slub.c:3519 mt_alloc_one lib/maple_tree.c:162 [inline] mas_alloc_nodes+0x2f8/0x8c0 lib/maple_tree.c:1267 mas_node_count_gfp lib/maple_tree.c:1347 [inline] mas_preallocate+0xa62/0x11d0 lib/maple_tree.c:5535 vma_iter_prealloc mm/internal.h:1152 [inline] __mmap_region mm/mmap.c:2783 [inline] mmap_region+0xd5a/0x2000 mm/mmap.c:2941 do_mmap+0x92c/0x10a0 mm/mmap.c:1385 vm_mmap_pgoff+0x1c4/0x3f0 mm/util.c:556 elf_map+0x19e/0x2f0 fs/binfmt_elf.c:380 elf_load+0x86/0x3b0 fs/binfmt_elf.c:398 load_elf_binary+0x10a8/0x2860 fs/binfmt_elf.c:1205 search_binary_handler fs/exec.c:1775 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xb08/0x1700 fs/exec.c:1892 do_execveat_common+0x51b/0x6c0 fs/exec.c:1998 do_execve fs/exec.c:2072 [inline] __do_sys_execve fs/exec.c:2148 [inline] __se_sys_execve fs/exec.c:2143 [inline] __x64_sys_execve+0x92/0xa0 fs/exec.c:2143 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f54a4d56107 Code: Unable to access opcode bytes at 0x7f54a4d560dd. RSP: 002b:00007ffc7367dc98 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055693e910fe0 RCX: 00007f54a4d56107 RDX: 000055693e911000 RSI: 000055693e910fe0 RDI: 000055693e911088 RBP: 000055693e911088 R08: 00007ffc7367fde9 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 000055693e911000 R13: 00007f54a4f1be8b R14: 000055693e911000 R15: 0000000000000000