INFO: task syz.1.4257:29341 blocked for more than 143 seconds. Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.4257 state:D stack:25008 pid:29341 tgid:29341 ppid:28855 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline] __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x705/0xa40 kernel/locking/rwsem.c:1526 filemap_invalidate_lock_shared include/linux/fs.h:870 [inline] filemap_fault+0xd54/0x1950 mm/filemap.c:3350 __do_fault+0x135/0x460 mm/memory.c:4871 do_shared_fault mm/memory.c:5350 [inline] do_fault mm/memory.c:5424 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x1105/0x6800 mm/memory.c:5755 __handle_mm_fault mm/memory.c:5898 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6066 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fa1b9b45a98 RSP: 002b:00007fa1b9e5fb88 EFLAGS: 00010202 RAX: 0000000020000000 RBX: 0000000000000004 RCX: 00236365632f7665 RDX: 000000000000000a RSI: 6365632f7665642f RDI: 0000000020000000 RBP: 00007fa1b9d35f8c R08: 00007fa1b9a00000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 0000000000000000 R13: 00007fa1b9d35f80 R14: 0000000000000003 R15: fffffffffffffffe Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 4 locks held by kworker/u8:2/35: 2 locks held by dhcpcd/4901: #0: ffff8880487d66c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: netlink_dump+0xcb/0xd80 net/netlink/af_netlink.c:2272 #1: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6534 2 locks held by getty/4983: #0: ffff88802dbfc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by kworker/0:3/5229: 3 locks held by kworker/u8:1/17138: #0: ffff88802d825948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88802d825948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90008be7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90008be7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 3 locks held by kworker/u8:4/19877: #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: ffffc90003fd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003fd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by syz.0.4220/29200: #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:860 [inline] #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x20e/0x490 block/fops.c:808 2 locks held by syz.1.4257/29341: #0: ffff88807e967070 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:704 [inline] #0: ffff88807e967070 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x34b/0x790 mm/memory.c:6232 #1: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:870 [inline] #1: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_fault+0xd54/0x1950 mm/filemap.c:3350 1 lock held by syz-executor/30609: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by syz-executor/30710: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by syz.0.4538/30779: #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:870 [inline] #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: page_cache_ra_unbounded+0x135/0x8a0 mm/readahead.c:226 1 lock held by syz.0.4538/30787: #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:870 [inline] #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: page_cache_ra_unbounded+0x135/0x8a0 mm/readahead.c:226 1 lock held by syz.0.4538/30788: #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:870 [inline] #0: ffff888148cd7c40 (mapping.invalidate_lock#2){++++}-{3:3}, at: page_cache_ra_unbounded+0x135/0x8a0 mm/readahead.c:226 1 lock held by syz-executor/30842: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by syz-executor/30880: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48c/0x2400 drivers/net/tun.c:3121 1 lock held by syz.4.4555/30894: #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 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: 2545 Comm: kworker/u8:6 Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound kfree_rcu_work RIP: 0010:preempt_latency_start kernel/sched/core.c:5779 [inline] RIP: 0010:preempt_count_add+0xaa/0x190 kernel/sched/core.c:5802 Code: ff 7f 39 d8 75 44 4c 8b 74 24 18 4c 89 f7 e8 ad 6c 0e 00 85 c0 74 0a 45 31 f6 31 ff e8 9f 6c 0e 00 65 48 8b 1c 25 c0 d7 03 00 <48> 81 c3 c8 14 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 RSP: 0018:ffffc90008db7760 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88802d565a00 RCX: ffffffff8bd05a00 RDX: 0000000000000000 RSI: ffffffff8c610280 RDI: 0000000000000000 RBP: ffffc90008db7810 R08: ffffffff901cfeef R09: 1ffffffff2039fdd R10: dffffc0000000000 R11: fffffbfff2039fde R12: 0000000000000246 R13: 1ffff920011b6ef0 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2397ac5ff0 CR3: 000000007f3e4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0xba/0x120 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:978 [inline] debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1019 slab_free_hook mm/slub.c:2273 [inline] slab_free_freelist_hook mm/slub.c:2371 [inline] slab_free_bulk mm/slub.c:4603 [inline] kmem_cache_free_bulk+0x261/0x530 mm/slub.c:4847 kfree_bulk include/linux/slab.h:767 [inline] kvfree_rcu_bulk+0x24b/0x4e0 kernel/rcu/tree.c:3385 kfree_rcu_work+0x44b/0x500 kernel/rcu/tree.c:3464 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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