INFO: task syz.7.1928:22096 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.1928 state:D stack:27368 pid:22096 tgid:22093 ppid:21007 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 __rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1466 [inline] down_read+0x132/0x200 kernel/locking/rwsem.c:1539 filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] do_page_cache_ra mm/readahead.c:333 [inline] page_cache_ra_order+0x2a5/0x4b0 mm/readahead.c:538 filemap_get_pages+0x47c/0x1ea0 mm/filemap.c:2695 filemap_splice_read+0x5d3/0xd20 mm/filemap.c:3084 do_splice_read fs/splice.c:980 [inline] splice_direct_to_actor+0x483/0xc80 fs/splice.c:1084 do_splice_direct_actor fs/splice.c:1202 [inline] do_splice_direct+0x19b/0x2a0 fs/splice.c:1228 do_sendfile+0x547/0x7e0 fs/read_write.c:1372 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419 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: 0033:0x7efc4b70c819 RSP: 002b:00007efc4995e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007efc4b985fa0 RCX: 00007efc4b70c819 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 00007efc4b7a2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efc4b986038 R14: 00007efc4b985fa0 R15: 00007ffd4fb11708 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: 1 lock held by khungtaskd/38: #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 8 locks held by kworker/u8:6/151: 3 locks held by kworker/u8:9/1161: #0: ffff888032d63938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888032d63938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90005effc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90005effc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffffffff8f15d338 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f15d338 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198 3 locks held by kworker/u9:1/5115: #0: ffff8880669f9938 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff8880669f9938 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90010e0fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90010e0fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff8880762e0f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 1 lock held by udevd/5165: 2 locks held by getty/5551: #0: ffff888037bf60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by syz.0.1902/21921: 1 lock held by syz.7.1928/22096: #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: do_page_cache_ra mm/readahead.c:333 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x2a5/0x4b0 mm/readahead.c:538 1 lock held by syz.8.1992/22489: #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: do_page_cache_ra mm/readahead.c:333 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x2a5/0x4b0 mm/readahead.c:538 1 lock held by udevd/22642: 2 locks held by udevd/22768: 1 lock held by syz.2.1997/22780: #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: do_page_cache_ra mm/readahead.c:333 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x2a5/0x4b0 mm/readahead.c:538 1 lock held by syz.3.2079/23318: #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: do_page_cache_ra mm/readahead.c:333 [inline] #0: ffff888026371840 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x2a5/0x4b0 mm/readahead.c:538 1 lock held by syz.1.2100/23478: #0: ffff888026371670 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff888026371670 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854 6 locks held by syz-executor/23499: 2 locks held by syz-executor/23653: #0: ffffffff8f6a8dd8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8f6a8dd8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8f6a8dd8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f15d338 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f15d338 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f15d338 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4093 1 lock held by syz.9.2120/23670: #0: ffff88804bdfa0d0 (&type->s_umount_key#62/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345 1 lock held by syz.6.2122/23690: #0: ffff88805c7be098 (&ctx->uring_lock){+.+.}-{4:4}, at: __do_sys_io_uring_register io_uring/register.c:1042 [inline] #0: ffff88805c7be098 (&ctx->uring_lock){+.+.}-{4:4}, at: __se_sys_io_uring_register+0x20b/0x1910 io_uring/register.c:1020 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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:161 [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:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 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: 22768 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:153 [inline] RIP: 0010:lock_is_held_type+0xf3/0x150 kernel/locking/lockdep.c:5942 Code: 0f 94 c3 eb 05 bb 01 00 00 00 48 c7 c7 56 20 7c 8d e8 21 18 00 00 b8 ff ff ff ff 65 0f c1 05 f4 f0 2a 07 83 f8 01 75 25 9c 58 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 5b 41 5c RSP: 0018:ffffc90004937230 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 0000000000000000 RSI: ffffffff8d7c2056 RDI: ffffffff8ba67a80 RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10035082fb R12: 0000000000000246 R13: ffff888029809e80 R14: ffffffff8e56c5b8 R15: 0000000000000001 FS: 00007fae5eeeb880(0000) GS:ffff888126332000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae5e59e000 CR3: 000000005a2ce000 CR4: 00000000003526f0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] depot_fetch_stack+0x31/0xa0 lib/stackdepot.c:503 dec_stack_record_count mm/page_owner.c:234 [inline] __reset_page_owner+0xd0/0x1f0 mm/page_owner.c:332 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] free_unref_folios+0xe7b/0x1c70 mm/page_alloc.c:3040 folios_put_refs+0x56f/0x680 mm/swap.c:1002 free_pages_and_swap_cache+0x2e7/0x5b0 mm/swap_state.c:423 __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:398 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:405 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:530 unmap_region+0x2a5/0x330 mm/vma.c:488 vms_clear_ptes mm/vma.c:1284 [inline] vms_complete_munmap_vmas+0x493/0xc60 mm/vma.c:1326 do_vmi_align_munmap+0x3bd/0x4d0 mm/vma.c:1585 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1633 __vm_munmap+0x22c/0x3d0 mm/vma.c:3261 __do_sys_munmap mm/mmap.c:1078 [inline] __se_sys_munmap mm/mmap.c:1075 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1075 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: 0033:0x7fae5f050097 Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc29995168 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 0000564a9bed9e10 RCX: 00007fae5f050097 RDX: 0000564a9bec8868 RSI: 0000000000040000 RDI: 00007fae5e53a000 RBP: 0000000000000018 R08: 0000000000000040 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 0000564a9beca0b0 R13: 00007fae5f72f39c R14: 0000000000042e00 R15: 0000000000000009