INFO: task syz-executor:4268 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22032 pid:4268 ppid:1 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 __filemap_get_folio+0x423/0xdb0 mm/filemap.c:1959 truncate_inode_pages_range+0x402/0x1090 mm/truncate.c:402 evict+0x4dc/0x8d0 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x60c/0x6a0 fs/inode.c:792 generic_shutdown_super+0x93/0x340 fs/super.c:480 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3c44b9d9d7 RSP: 002b:00007ffc5ef771e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f3c44c32050 RCX: 00007f3c44b9d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc5ef772a0 RBP: 00007ffc5ef772a0 R08: 00007ffc5ef782a0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc5ef78330 R13: 00007f3c44c32050 R14: 000000000001b828 R15: 00007ffc5ef78370 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2dfb0 (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: ffffffff8cb2e7d0 (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/28: #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4029: #0: ffff88814d8f0098 (&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 3 locks held by syz-executor/4267: 1 lock held by syz-executor/4268: #0: ffff88802f08a0e0 (&type->s_umount_key#87){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz.5.1040/7052: #0: ffff88802f08a0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755 1 lock held by syz-executor/7404: 2 locks held by syz.0.1237/7534: #0: ffff88807b85a460 (sb_writers#3){.+.+}-{0:0}, at: do_sendfile+0x5d0/0xea0 fs/read_write.c:1254 #1: ffff88802f08a0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755 2 locks held by syz.3.1425/8040: 3 locks held by dhcpcd-run-hook/8056: 1 lock held by syz.7.1433/8058: 5 locks held by syz.4.1434/8060: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 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: 7404 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:preempt_count_add+0x11f/0x190 kernel/sched/core.c:5706 Code: ff 48 c7 c7 e0 a1 8b 8a 48 c7 c6 20 a2 8b 8a e8 c7 f9 f4 ff 89 df 0f 0b e9 5e ff ff ff 48 c7 c1 40 d1 bf 96 80 e1 07 80 c1 03 <38> c1 0f 8c 00 ff ff ff 89 fb 48 c7 c7 40 d1 bf 96 e8 7b 73 7a 00 RSP: 0018:ffffc9001e717390 EFLAGS: 00000206 RAX: 0000000000000004 RBX: ffffc9001e717488 RCX: ffffffff96bfd103 RDX: dffffc0000000000 RSI: ffffffff816f4096 RDI: 0000000000000001 RBP: ffffc9001e7174d0 R08: ffffc9001e717550 R09: 000000000000000f R10: dffffc0000000000 R11: fffff52003ce2e9d R12: ffffffff816f4096 R13: ffffc9001e717ed0 R14: dffffc0000000000 R15: dffffc0000000000 FS: 0000555584422500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2f5f6347e8 CR3: 0000000077766000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xaf/0x20b0 arch/x86/kernel/unwind_orc.c:433 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] kmem_cache_free+0xf7/0x290 mm/slub.c:3709 free_buffer_head+0x45/0xb0 fs/buffer.c:2919 try_to_free_buffers+0x283/0x560 fs/buffer.c:2860 block_invalidate_folio+0x5ff/0x9e0 fs/buffer.c:1526 folio_invalidate mm/truncate.c:158 [inline] truncate_cleanup_folio+0x218/0x5e0 mm/truncate.c:178 truncate_inode_pages_range+0x293/0x1090 mm/truncate.c:393 kill_bdev block/bdev.c:76 [inline] blkdev_flush_mapping+0x12c/0x290 block/bdev.c:681 blkdev_put_whole block/bdev.c:712 [inline] blkdev_put+0x47f/0x710 block/bdev.c:972 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fedc239d9d7 Code: a2 c7 05 1c fd 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffc7aa267d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fedc2432050 RCX: 00007fedc239d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc7aa26890 RBP: 00007ffc7aa26890 R08: 00007ffc7aa27890 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc7aa27920 R13: 00007fedc2432050 R14: 0000000000040cca R15: 00007ffc7aa27960