INFO: task syz.4.1342:11040 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1342 state:D stack:25096 pid:11040 tgid:11040 ppid:5840 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16aa/0x4c90 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0x165/0x360 kernel/sched/core.c:6879 request_wait_answer fs/fuse/dev.c:565 [inline] __fuse_request_send fs/fuse/dev.c:579 [inline] __fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:673 fuse_simple_request fs/fuse/fuse_i.h:1237 [inline] fuse_flush+0x5d4/0x800 fs/fuse/file.c:475 filp_flush+0xba/0x190 fs/open.c:1549 filp_close+0x1d/0x40 fs/open.c:1562 __range_close fs/file.c:752 [inline] __do_sys_close_range fs/file.c:811 [inline] __se_sys_close_range+0x359/0x650 fs/file.c:775 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa72218ebe9 RSP: 002b:00007fff8d4124d8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007fa7223b7da0 RCX: 00007fa72218ebe9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fa7223b7da0 R08: 00000000000000d0 R09: 0000000c8d4127cf R10: 00007fa7223b7cb0 R11: 0000000000000246 R12: 000000000008c19b R13: 00007fa7223b6090 R14: ffffffffffffffff R15: 00007fff8d4125f0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5597: #0: ffff88814c9d70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 5 locks held by kworker/u8:20/12778: 1 lock held by syz.2.1873/13084: #0: ffff88807fafb3e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:374 [inline] #0: ffff88807fafb3e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1bd/0x4c0 mm/util.c:577 1 lock held by syz.2.1873/13085: 1 lock held by syz.2.1873/13091: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13085 Comm: syz.2.1873 Not tainted 6.16.0-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__lock_acquire+0x85b/0xd20 kernel/locking/lockdep.c:-1 Code: 89 f0 c1 c0 08 29 f1 31 c8 01 d6 29 c2 89 c1 c1 c1 10 31 d1 01 f0 41 89 cf 41 c1 c7 13 29 ce 41 31 f7 01 c1 44 29 f8 44 01 f9 <41> c1 c7 04 41 31 c7 49 c1 e7 20 49 09 cf 83 3d 84 9f 02 0e 00 0f RSP: 0018:ffffc9001b9d7418 EFLAGS: 00000096 RAX: 00000000f0af209b RBX: 0000000000000005 RCX: 00000000fef07a87 RDX: 00000000d59ecd1d RSI: 00000000576e5d05 RDI: ffff888020b53c00 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81f5fcdc R10: 0000000000000406 R11: 0000000000000002 R12: 0000000072168d09 R13: ffff888020b546f0 R14: ffff888020b547b8 R15: 00000000ad1bfd4f FS: 00007f7053f926c0(0000) GS:ffff888125d57000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdf62584198 CR3: 000000007a71c000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] page_ref_add_unless include/linux/page_ref.h:235 [inline] folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get+0x38/0x340 include/linux/page_ref.h:264 next_uptodate_folio+0xcb/0x5d0 mm/filemap.c:3572 filemap_map_pages+0x1025/0x1740 mm/filemap.c:3755 do_fault_around mm/memory.c:5548 [inline] do_read_fault mm/memory.c:5581 [inline] do_fault mm/memory.c:5724 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6069 [inline] __handle_mm_fault+0x368a/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 faultin_page mm/gup.c:1186 [inline] __get_user_pages+0x1af4/0x30b0 mm/gup.c:1488 populate_vma_page_range+0x26b/0x340 mm/gup.c:1926 __mm_populate+0x24c/0x380 mm/gup.c:2029 mm_populate include/linux/mm.h:3353 [inline] vm_mmap_pgoff+0x3f0/0x4c0 mm/util.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f705318ebe9 Code: ff ff c3 66 2e 0f 1f 84 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 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7053f92038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f70533b5fa0 RCX: 00007f705318ebe9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f7053211e19 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f70533b6038 R14: 00007f70533b5fa0 R15: 00007ffeee8a55d8