INFO: task syz-executor:6639 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20272 pid:6639 tgid:6639 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 io_schedule+0x80/0xd0 kernel/sched/core.c:7789 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 __folio_lock mm/filemap.c:1699 [inline] folio_lock include/linux/pagemap.h:1159 [inline] __filemap_get_folio_mpol+0x13e/0xb00 mm/filemap.c:1954 __filemap_get_folio include/linux/pagemap.h:763 [inline] truncate_inode_pages_range+0x3f0/0xd90 mm/truncate.c:413 evict+0x607/0xae0 fs/inode.c:839 dispose_list fs/inode.c:879 [inline] evict_inodes+0x753/0x7e0 fs/inode.c:933 generic_shutdown_super+0x9a/0x2c0 fs/super.c:628 kill_block_super+0x44/0x90 fs/super.c:1722 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9e80b90a77 RSP: 002b:00007ffddba4e498 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9e80c13d7d RCX: 00007f9e80b90a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffddba4e550 RBP: 00007ffddba4e550 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffddba4f5e0 R13: 00007f9e80c13d7d R14: 0000000000034f3c R15: 00007ffddba4f620 Showing all locks held in the system: 1 lock held by rcu_tasks_trace/29: #0: ffffffff8df42730 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{4:4}, at: rcu_tasks_one_gp+0xaf9/0xdf0 kernel/rcu/tasks.h:614 1 lock held by khungtaskd/32: #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by dhcpcd/5487: #0: ffffffff8f311b48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f311b48 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b20 net/ipv4/devinet.c:1120 2 locks held by getty/5579: #0: ffff888034a040a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 4 locks held by kworker/1:4/5891: #0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc900040bfb80 (ser_release_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900040bfb80 (ser_release_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8f311b48 (rtnl_mutex){+.+.}-{4:4}, at: ser_release+0x107/0x240 drivers/net/caif/caif_serial.c:293 #3: ffffffff8df47538 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #3: ffffffff8df47538 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956 1 lock held by syz-executor/6639: #0: ffff888051a040e0 (&type->s_umount_key#98){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888051a040e0 (&type->s_umount_key#98){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888051a040e0 (&type->s_umount_key#98){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 1 lock held by syz.6.395/7995: #0: ffff888051a040e0 (&type->s_umount_key#98){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff888051a040e0 (&type->s_umount_key#98){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 4 locks held by syz.1.473/9192: 2 locks held by syz.9.602/9300: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9192 Comm: syz.1.473 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:121 [inline] RIP: 0010:lock_acquire+0x98/0x340 kernel/locking/lockdep.c:5844 Code: 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 0c 68 89 00 83 3d 55 d9 e3 0d 00 0f 84 fa 00 00 00 65 8b 05 58 80 e0 10 <85> c0 0f 85 eb 00 00 00 65 48 8b 04 25 08 b0 7e 92 83 b8 2c 0b 00 RSP: 0018:ffffc900053f60e0 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: db3f8d2168da6300 RDX: 0000000000000000 RSI: ffffffff8231e747 RDI: 1ffffffff1be833c RBP: ffffffff8231e72a R08: 0000000000000000 R09: 0000000000000000 R10: ffff88802e160900 R11: ffffffff81ada000 R12: 0000000000000002 R13: ffffffff8df419e0 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f5ca9c5d6c0(0000) GS:ffff888125f35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff864d26000 CR3: 000000002f55e000 CR4: 0000000000350ef0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] __update_page_owner_handle+0x77/0x570 mm/page_owner.c:255 __set_page_owner+0x10b/0x4c0 mm/page_owner.c:342 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1890 [inline] shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1932 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2556 shmem_get_folio mm/shmem.c:2662 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3315 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3490 __kernel_write_iter+0x428/0x910 fs/read_write.c:619 dump_emit_page fs/coredump.c:1298 [inline] dump_user_range+0x8a0/0xc90 fs/coredump.c:1372 elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111 coredump_write+0x1121/0x18b0 fs/coredump.c:1049 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200 get_signal+0x1108/0x1340 kernel/signal.c:3019 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x177/0x660 kernel/entry/common.c:196 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f5ca8d8f751 Code: 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 48 3d 01 f0 ff ff 73 01 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:00000000fffffe10 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f5ca8fe5fa0 RCX: 00007f5ca8d8f749 RDX: 0000000000000000 RSI: 00000000fffffe10 RDI: 0000000000000000 RBP: 00007f5ca8e13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5ca8fe6038 R14: 00007f5ca8fe5fa0 R15: 00007ffc721decb8