INFO: task syz.3.1368:3851 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.1368 state:D stack:0 pid:3851 tgid:3851 ppid:292 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 request_wait_answer fs/fuse/dev.c:477 [inline] __fuse_request_send fs/fuse/dev.c:493 [inline] __fuse_simple_request+0xdee/0x1b10 fs/fuse/dev.c:588 fuse_simple_request fs/fuse/fuse_i.h:1248 [inline] fuse_flush+0xad9/0x2020 fs/fuse/file.c:602 filp_flush fs/open.c:1552 [inline] filp_close+0xc0/0x160 fs/open.c:1565 __range_close fs/file.c:726 [inline] __close_range+0x32a/0x4c0 fs/file.c:792 __do_sys_close_range fs/open.c:1618 [inline] __se_sys_close_range fs/open.c:1615 [inline] __x64_sys_close_range+0x7e/0x90 fs/open.c:1615 x64_sys_call+0x1686/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:437 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f5a8df9c819 RSP: 002b:00007fffbd5bef18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007f5a8e217da0 RCX: 00007f5a8df9c819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f5a8e217da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f5a8e217cb0 R11: 0000000000000246 R12: 000000000001e4e9 R13: 00007f5a8e21609c R14: 000000000001e24f R15: 00007f5a8e216090 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 6df8a48c60291494d9389e53691a3df5daca5615 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c6/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10458 Comm: syz.2.4269 Not tainted syzkaller #0 6df8a48c60291494d9389e53691a3df5daca5615 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:folio_test_swapbacked include/linux/page-flags.h:547 [inline] RIP: 0010:mm_counter_file include/linux/mm.h:2801 [inline] RIP: 0010:mm_counter include/linux/mm.h:2810 [inline] RIP: 0010:zap_present_folio_ptes mm/memory.c:1520 [inline] RIP: 0010:zap_present_ptes mm/memory.c:1593 [inline] RIP: 0010:zap_pte_range mm/memory.c:1636 [inline] RIP: 0010:zap_pmd_range mm/memory.c:1766 [inline] RIP: 0010:zap_pud_range mm/memory.c:1795 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1816 [inline] RIP: 0010:unmap_page_range+0x19dd/0x3fa0 mm/memory.c:1837 Code: 5e e8 97 dd b7 ff 48 8b 5c 24 40 48 89 df be 08 00 00 00 e8 45 16 10 00 48 b8 00 00 00 00 00 fc ff df 48 8b 8c 24 c0 00 00 00 <80> 3c 01 00 74 08 48 89 df e8 55 13 10 00 48 8b 33 48 89 f3 48 c1 RSP: 0018:ffffc90008aef540 EFLAGS: 00000256 RAX: dffffc0000000000 RBX: ffffea00048c85c0 RCX: 1ffffd40009190b8 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea00048c85c0 RBP: ffffc90008aef770 R08: ffffea00048c85c7 R09: 1ffffd40009190b8 R10: dffffc0000000000 R11: fffff940009190b9 R12: 8000000123217007 R13: 0000000000000000 R14: ffffea00048c85d8 R15: 00007f90a7848000 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc9040dca0 CR3: 0000000114980000 CR4: 00000000003526b0 DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081 DR3: ffffffffefffff14 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: unmap_single_vma mm/memory.c:1883 [inline] unmap_vmas+0x2d2/0x3f0 mm/memory.c:1927 exit_mmap+0x29c/0xbc0 mm/mmap.c:1971 __mmput+0x93/0x340 kernel/fork.c:1359 mmput+0x55/0x170 kernel/fork.c:1383 exit_mm kernel/exit.c:574 [inline] do_exit+0x909/0x2720 kernel/exit.c:941 do_group_exit+0x229/0x2f0 kernel/exit.c:1096 get_signal+0x1398/0x14e0 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x760 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f90a8d9c819 Code: Unable to access opcode bytes at 0x7f90a8d9c7ef. RSP: 002b:00007f90a9b8a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f90a9016098 RCX: 00007f90a8d9c819 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f90a9016098 RBP: 00007f90a9016090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f90a9016128 R14: 00007ffe20c51160 R15: 00007ffe20c51248