INFO: task syz.0.402:7498 blocked for more than 143 seconds. Tainted: G L syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.402 state:D stack:25760 pid:7498 tgid:7498 ppid:5843 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 mmap_read_lock include/linux/mmap_lock.h:592 [inline] exit_mm+0x73/0x250 kernel/exit.c:557 do_exit+0x8b9/0x2490 kernel/exit.c:962 do_group_exit+0x21b/0x2d0 kernel/exit.c:1116 __do_sys_exit_group kernel/exit.c:1127 [inline] __se_sys_exit_group kernel/exit.c:1125 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1125 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb50fd9c799 RSP: 002b:00007ffede6d82f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007fb50fd9c799 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000b RBP: 00000000000000f7 R08: 00007ffede6d87a7 R09: 000000000000000b R10: 00007fb510015fa0 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fb51001627c R14: 00007fb510016278 R15: 00007fb510016270 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5606: #0: ffff8880329fc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.0.402/7498: #0: ffff88807d27dab8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff88807d27dab8 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline] watchdog+0x1002/0x1060 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 5831 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:account_numa_dequeue kernel/sched/fair.c:1727 [inline] RIP: 0010:account_entity_dequeue kernel/sched/fair.c:3841 [inline] RIP: 0010:dequeue_entity kernel/sched/fair.c:5629 [inline] RIP: 0010:dequeue_entities+0x8a3/0x3820 kernel/sched/fair.c:7281 Code: 20 84 c0 0f 85 52 08 00 00 41 8b 3e e8 b6 02 e2 ff 45 31 f6 39 c5 40 0f 94 c5 48 83 c3 08 48 89 d8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 47 08 00 00 41 88 ee 41 f7 de 44 01 33 49 8d 5f 48 48 RSP: 0018:ffffc900038e7838 EFLAGS: 00000806 RAX: 0000000000000000 RBX: ffff8880b843ad88 RCX: ffff88807d165b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 0000000000000001 R08: ffffffff905444f7 R09: 1ffffffff20a889e R10: dffffc0000000000 R11: fffffbfff20a889f R12: dffffc0000000000 R13: ffff8880b843ae40 R14: 0000000000000000 R15: ffff88807d165c00 FS: 0000555566101540(0000) GS:ffff888124de1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fddfc7e92f8 CR3: 0000000075334000 CR4: 00000000003526f0 Call Trace: dequeue_task_fair+0x200/0x670 kernel/sched/fair.c:7377 block_task kernel/sched/core.c:2223 [inline] try_to_block_task kernel/sched/core.c:6587 [inline] __schedule+0x6da/0x5590 kernel/sched/core.c:6899 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 do_nanosleep+0x1c2/0x620 kernel/time/hrtimer.c:2292 hrtimer_nanosleep+0x18f/0x3a0 kernel/time/hrtimer.c:2338 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline] __se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f71f1d57917 Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffd9e495020 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000555566101540 RCX: 00007f71f1d57917 RDX: 00007ffd9e495060 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffd9e495540 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004 R13: 00007ffd9e49509c R14: 00007ffd9e495130 R15: 0000000000000000