INFO: task syz.3.21:6103 blocked for more than 143 seconds. Not tainted syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.21 state:D stack:23064 pid:6103 tgid:6098 ppid:5986 task_flags:0x40044c 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 get_signal+0x1284/0x1330 kernel/signal.c:3035 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e1379c799 RSP: 002b:00007f5e1466c0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f5e13a16098 RCX: 00007f5e1379c799 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5e13a16098 RBP: 00007f5e13a16090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5e13a16128 R14: 00007ffd97474b90 R15: 00007ffd97474c78 Showing all locks held in the system: 1 lock held by khungtaskd/30: #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/5587: #0: ffff88823bf628a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.3.21/6103: #0: ffff888065cc6738 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff888065cc6738 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557 1 lock held by syz.1.507/8083: #0: ffff88813fe2ce38 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff88813fe2ce38 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557 1 lock held by syz.1.507/8087: #0: ffff88813fe2ce38 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff88813fe2ce38 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557 1 lock held by syz.5.655/8695: #0: ffff88813fe28338 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff88813fe28338 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x234/0x4f0 mm/util.c:579 1 lock held by syz.5.655/8696: 2 locks held by syz.4.656/8699: 1 lock held by syz.2.657/8700: #0: ffff888079bc73b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff888079bc73b8 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x234/0x4f0 mm/util.c:579 1 lock held by syz.2.657/8701: 1 lock held by syz.0.658/8704: #0: ffff888079bc6738 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff888079bc6738 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x234/0x4f0 mm/util.c:579 1 lock held by syz.0.658/8705: #0: ffff888079bc6738 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff888079bc6738 (&mm->mmap_lock){++++}-{4:4}, at: do_mlock+0x173/0x750 mm/mlock.c:632 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 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: 8709 Comm: syz.5.655 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:stack_trace_consume_entry+0xf3/0x280 kernel/stacktrace.c:93 Code: 8b 74 24 08 48 8b 1f 45 8d 79 01 0f b6 44 15 00 84 c0 0f 85 3a 01 00 00 45 89 38 4e 8d 3c cb 4c 89 f8 48 c1 e8 03 80 3c 10 00 <74> 1a 4c 89 ff 48 89 f3 49 89 d4 4c 89 c5 e8 fa 3b 7e 00 49 89 e8 RSP: 0018:ffffc900044c7038 EFLAGS: 00000246 RAX: 1ffff92000898e46 RBX: ffffc900044c7200 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff8186a6b8 RDI: ffffc900044c7140 RBP: 1ffff92000898e2a R08: ffffc900044c7150 R09: 0000000000000006 R10: ffffc900044c70d8 R11: ffffffff81b21b00 R12: 0000000000000000 R13: 1ffff92000898e29 R14: ffffc900044c7148 R15: ffffc900044c7230 FS: 0000000000000000(0000) GS:ffff888124de0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4598fe7158 CR3: 000000007a5f4000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x10f/0x150 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1401 [inline] free_unref_folios+0xd0c/0x1450 mm/page_alloc.c:3003 folios_put_refs+0x9ff/0xb40 mm/swap.c:1008 free_pages_and_swap_cache+0x2b9/0x490 mm/swap_state.c:401 __tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline] tlb_batch_pages_flush mm/mmu_gather.c:151 [inline] tlb_flush_mmu_free mm/mmu_gather.c:417 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:424 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:549 exit_mmap+0x498/0xa10 mm/mmap.c:1315 __mmput+0x118/0x430 kernel/fork.c:1180 exit_mm+0x18e/0x250 kernel/exit.c:581 do_exit+0x8b9/0x2490 kernel/exit.c:962 do_group_exit+0x21b/0x2d0 kernel/exit.c:1116 get_signal+0x1284/0x1330 kernel/signal.c:3035 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3e8eb9c799 Code: Unable to access opcode bytes at 0x7f3e8eb9c76f. RSP: 002b:00007f3e8fae80e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f3e8ee16188 RCX: 00007f3e8eb9c799 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f3e8ee1618c RBP: 00007f3e8ee16180 R08: 3fffffffffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3e8ee16218 R14: 00007ffd0a3fb480 R15: 00007ffd0a3fb568