INFO: task syz.0.391:6793 blocked for more than 144 seconds. Not tainted 6.12.0-rc6-next-20241108-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.391 state:D stack:25328 pid:6793 tgid:6792 ppid:5926 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6753 __schedule_loop kernel/sched/core.c:6830 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6845 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6902 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 fdget_pos+0x254/0x320 fs/file.c:1191 class_fd_pos_constructor include/linux/file.h:85 [inline] ksys_lseek fs/read_write.c:389 [inline] __do_sys_lseek fs/read_write.c:405 [inline] __se_sys_lseek fs/read_write.c:403 [inline] __x64_sys_lseek+0x7a/0x1e0 fs/read_write.c:403 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0aae37e719 RSP: 002b:00007f0aaf21d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 RAX: ffffffffffffffda RBX: 00007f0aae535f80 RCX: 00007f0aae37e719 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f0aae3f1616 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0aae535f80 R15: 00007ffc64a71538 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd01a8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by khungtaskd/30: #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by kworker/u8:3/52: 2 locks held by getty/5593: #0: ffff8880315670a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032432f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.0.391/6793: #0: ffff888033a549b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1191 2 locks held by syz.0.391/6799: 2 locks held by syz.4.657/7346: 1 lock held by syz.1.908/7878: #0: ffff88807641a478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1191 2 locks held by syz.1.908/7883: 2 locks held by syz.5.926/7917: 1 lock held by syz-executor/7991: #0: ffffffff8fcd01a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd01a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6796 2 locks held by syz-executor/8016: #0: ffffffff8fcc3650 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:497 #1: ffffffff8fcd01a8 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-next-20241108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xffb/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 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: 7917 Comm: syz.5.926 Not tainted 6.12.0-rc6-next-20241108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:79 [inline] RIP: 0010:preempt_count_add+0x3d/0x190 kernel/sched/core.c:5846 Code: c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d 8c 80 ce 18 00 75 07 65 8b 05 8b 5b 96 7e <65> 01 1d 84 5b 96 7e 48 c7 c0 c0 f9 3b 9a 48 c1 e8 03 42 0f b6 04 RSP: 0018:ffffc90004b2dd30 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000001 RCX: ffffffff9a3bf903 RDX: dffffc0000000000 RSI: ffffffff81e06d8c RDI: 0000000000000001 RBP: ffffc90004b2de58 R08: 000000000000000c R09: ffffc90004b2df10 R10: ffffc90004b2de70 R11: ffffffff818b2c40 R12: dffffc0000000000 R13: ffffc90004b2de20 R14: ffffffff81e06d8c R15: dffffc0000000000 FS: 00007fbf85eb26c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555739fd5c8 CR3: 0000000027668000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb0/0x22d0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 free_buffer_head+0x54/0x240 fs/buffer.c:3031 try_to_free_buffers+0x311/0x5f0 fs/buffer.c:2972 shrink_folio_list+0x240c/0x8cc0 mm/vmscan.c:1433 evict_folios+0x5568/0x7be0 mm/vmscan.c:4593 try_to_shrink_lruvec+0x9a6/0xc70 mm/vmscan.c:4789 lru_gen_shrink_lruvec mm/vmscan.c:4938 [inline] shrink_lruvec+0x541/0x31b0 mm/vmscan.c:5693 shrink_node_memcgs mm/vmscan.c:5929 [inline] shrink_node+0xb1d/0x3e60 mm/vmscan.c:5970 shrink_zones mm/vmscan.c:6215 [inline] do_try_to_free_pages+0x78c/0x1cf0 mm/vmscan.c:6277 try_to_free_mem_cgroup_pages+0x48c/0xad0 mm/vmscan.c:6609 try_charge_memcg+0x8c7/0x1150 mm/memcontrol.c:2238 try_charge mm/memcontrol-v1.h:19 [inline] charge_memcg+0xa6/0x1e0 mm/memcontrol.c:4497 __mem_cgroup_charge+0x27/0x80 mm/memcontrol.c:4512 mem_cgroup_charge include/linux/memcontrol.h:646 [inline] filemap_add_folio+0xb3/0x650 mm/filemap.c:966 do_read_cache_folio+0x341/0x850 mm/filemap.c:3793 read_mapping_folio include/linux/pagemap.h:1011 [inline] dir_get_folio fs/sysv/dir.c:64 [inline] sysv_readdir+0x193/0x540 fs/sysv/dir.c:93 iterate_dir+0x571/0x800 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:403 [inline] __se_sys_getdents64+0x1e2/0x4b0 fs/readdir.c:389 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbf8517e719 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:00007fbf85eb2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007fbf85335f80 RCX: 00007fbf8517e719 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007fbf851f1616 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbf85335f80 R15: 00007ffcbd38b0b8