INFO: task syz-executor:6626 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:17104 pid:6626 tgid:6626 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216 __writeback_inodes_sb_nr+0x1f6/0x250 fs/fs-writeback.c:2748 sync_filesystem+0xa3/0x230 fs/sync.c:54 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2576 deactivate_locked_super+0xb9/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9b4478ff17 RSP: 002b:00007ffea8bde858 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9b44811c05 RCX: 00007f9b4478ff17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffea8bde910 RBP: 00007ffea8bde910 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffea8bdf9a0 R13: 00007f9b44811c05 R14: 0000000000020ad5 R15: 00007ffea8bdf9e0 INFO: task syz.0.298:8109 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.298 state:D stack:24168 pid:8109 tgid:8108 ppid:5859 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1539 __super_lock fs/super.c:59 [inline] super_lock+0x2a9/0x3b0 fs/super.c:121 __iterate_supers+0x126/0x290 fs/super.c:923 ksys_sync+0x94/0x150 fs/sync.c:102 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f61b238ebe9 RSP: 002b:00007f61b32a5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f61b25b5fa0 RCX: 00007f61b238ebe9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f61b25b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f61b25b6038 R14: 00007f61b25b5fa0 R15: 00007fff1ea1a068 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11807 Comm: modprobe Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pmd_none arch/x86/include/asm/pgtable.h:1018 [inline] RIP: 0010:__handle_mm_fault+0x9f9/0x5400 mm/memory.c:6292 Code: 94 fd ff ff e9 97 fd ff ff 48 8b 9c 24 10 01 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 0a 44 18 00 48 8b 1b <48> 89 de 48 83 e6 9f 31 ff e8 09 9f b4 ff 48 83 e3 9f 4c 8d bc 24 RSP: 0000:ffffc900050e7be0 EFLAGS: 00000246 RAX: 1ffff1100b2517c9 RBX: 000000005928d067 RCX: ffff88807e458000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900050e7dc0 R08: 0000000000000004 R09: 0000000000000004 R10: ffffc900050e7cec R11: fffff52000a1cfa6 R12: dffffc0000000000 R13: ffff88808c681c80 R14: 0000000000000000 R15: ffff8880592a2b90 FS: 00007fdcb9065c80(0000) GS:ffff8881259ff000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdcb92fc008 CR3: 000000009d0f8000 CR4: 00000000003526f0 Call Trace: handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fdcb93e74ac Code: d0 48 83 c1 08 4c 01 10 48 8d 78 08 48 39 f1 73 35 48 8b 01 a8 01 74 e6 48 d1 e8 48 89 fa 74 16 66 0f 1f 44 00 00 a8 01 74 03 <4c> 01 12 48 83 c2 08 48 d1 e8 75 f0 48 83 c1 08 48 81 c7 f8 01 00 RSP: 002b:00007ffc78b8e510 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00007fdcb9155300 RDX: 00007fdcb92fc008 RSI: 00007fdcb9155400 RDI: 00007fdcb92fbe18 RBP: 00007ffc78b8e630 R08: 0000000000000000 R09: 00007fdcb940fda0 R10: 00007fdcb912e000 R11: 0000000000000203 R12: 0000000000000001 R13: 0000000000000000 R14: 00007fdcb93d05f0 R15: 0000000000000000