INFO: task syz.4.308:4492 blocked for more than 143 seconds. Not tainted 6.1.112-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.308 state:D stack:24512 pid:4492 ppid:3655 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 mmap_write_lock include/linux/mmap_lock.h:71 [inline] exit_mmap+0x29a/0x9f0 mm/mmap.c:3235 __mmput+0x115/0x3c0 kernel/fork.c:1199 exit_mm+0x226/0x300 kernel/exit.c:565 do_exit+0x9f6/0x26a0 kernel/exit.c:858 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 get_signal+0x16f7/0x17d0 kernel/signal.c:2870 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8f35b7dff9 RSP: 002b:00007f8f359ff0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f8f35d35f88 RCX: 00007f8f35b7dff9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8f35d35f8c RBP: 00007f8f35d35f80 R08: 0000000000000010 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 00007f8f35d35f8c R13: 0000000000000000 R14: 00007ffe59228f90 R15: 00007ffe59229078 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b1d0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b9d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 3 locks held by udevd/3093: 2 locks held by getty/3396: #0: ffff88814b7af098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 1 lock held by syz.4.308/4492: #0: ffff88801b7a0158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline] #0: ffff88801b7a0158 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x29a/0x9f0 mm/mmap.c:3235 4 locks held by dhcpcd-run-hook/4628: 1 lock held by syz.3.355/4646: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3093 Comm: udevd Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:lockdep_hardirqs_on+0x7f/0x130 kernel/locking/lockdep.c:4372 Code: 8c 0c 00 75 2e 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 63 83 3d 6a 95 8c 0c 00 75 10 48 8b 83 b8 0a 00 00 <48> 3b 83 d0 0a 00 00 75 73 48 c7 c7 40 03 0c 8b e8 ac 18 00 00 65 RSP: 0018:ffffc900031af878 EFLAGS: 00000046 RAX: 5c4873abf506c5fe RBX: ffff88807c6b8000 RCX: ffffffff816af0fa RDX: dffffc0000000000 RSI: ffffffff8b0c14c0 RDI: ffffffff8ab10f5b RBP: ffffc900031af938 R08: dffffc0000000000 R09: fffffbfff223ba59 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000635f14 R14: ffffffff8ab10f5b R15: 0000000000000246 FS: 00007ff5d4bb8c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc1fc2d8b8 CR3: 000000002d599000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x8b/0x130 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x455/0x4e0 lib/debugobjects.c:1008 free_pages_prepare mm/page_alloc.c:1450 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0x319/0x1120 mm/page_alloc.c:3369 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464 free_slab mm/slub.c:2031 [inline] discard_slab mm/slub.c:2037 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586 put_cpu_partial+0x17b/0x250 mm/slub.c:2662 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc_lru+0x10c/0x2d0 mm/slub.c:3429 __d_alloc+0x31/0x710 fs/dcache.c:1774 d_alloc+0x48/0x1d0 fs/dcache.c:1854 lookup_one_qstr_excl+0xca/0x240 fs/namei.c:1601 do_unlinkat+0x293/0x820 fs/namei.c:4376 __do_sys_unlink fs/namei.c:4440 [inline] __se_sys_unlink fs/namei.c:4438 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4438 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff5d4717da7 Code: f0 ff ff 73 01 c3 48 8b 0d 7e 90 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 90 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffde4e56ac8 EFLAGS: 00000202 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff5d4717da7 RDX: 0000000000000001 RSI: 00007ffde4e56ba0 RDI: 000055d95aba20d8 RBP: 000000000000000b R08: 000000001035ee98 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000bb8 R13: 0000000200000001 R14: 0000000000000001 R15: 0000000000000000