INFO: task syz.1.66:6231 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.66 state:D stack:22840 pid:6231 tgid:6230 ppid:5804 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] schedule+0x164/0x360 kernel/sched/core.c:7277 folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [inline] release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753 dtSplitPage+0x791/0x37c0 fs/jfs/jfs_dtree.c:1471 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0x10a4/0x5f10 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x783/0xb00 fs/jfs/namei.c:271 vfs_mkdir+0x40b/0x630 fs/namei.c:5261 filename_mkdirat+0x289/0x520 fs/namei.c:5294 __do_sys_mkdir fs/namei.c:5321 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5318 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5c3bc4c819 RSP: 002b:00007f5c39e9e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f5c3bec5fa0 RCX: 00007f5c3bc4c819 RDX: 0000000000000000 RSI: 000000000000014c RDI: 0000200000000180 RBP: 00007f5c3bce2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c3bec6038 R14: 00007f5c3bec5fa0 R15: 00007ffc3e1f99a8 INFO: task syz.1.66:6234 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.66 state:D stack:25528 pid:6234 tgid:6230 ppid:5804 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7558 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1659 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1776 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:245 inode_lock include/linux/fs.h:1029 [inline] open_last_lookups fs/namei.c:4608 [inline] path_openat+0xb5e/0x38a0 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5c3bc4c819 RSP: 002b:00007f5c39e7d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f5c3bec6090 RCX: 00007f5c3bc4c819 RDX: 000000000000275a RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f5c3bce2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c3bec6128 R14: 00007f5c3bec6090 R15: 00007ffc3e1f99a8 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88801e2d6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88801e2d6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3371 #1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3371 #2: ffff8880337280d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 3 locks held by kworker/u8:1/13: #0: ffff8880324e2138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff8880324e2138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3371 #1: ffffc90000127c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90000127c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3371 #2: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198 1 lock held by khungtaskd/39: #0: ffffffff8ddca400 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ddca400 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:847 [inline] #0: ffffffff8ddca400 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 6 locks held by kworker/u8:17/3589: #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3371 #1: ffffc9000ff4fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc9000ff4fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3371 #2: ffffffff8f14fe00 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673 #3: ffff8880222d1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff8880222d1160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880222d1160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x11b/0x3f0 net/devlink/core.c:504 #4: ffff8880254a0300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:274 [inline] #4: ffff8880254a0300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff8880254a0300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x12d/0x3f0 net/devlink/core.c:504 #5: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #5: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2162 2 locks held by getty/5560: #0: ffff88803747d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 4 locks held by syz.1.66/6231: #0: ffff888033728480 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880626722b0 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline] #1: ffff8880626722b0 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2914 [inline] #1: ffff8880626722b0 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2938 [inline] #1: ffff8880626722b0 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4950 #2: ffff888062671ee0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_mkdir+0x235/0xb00 fs/jfs/namei.c:234 #3: ffff8880624975c8 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_mkdir+0x250/0xb00 fs/jfs/namei.c:235 2 locks held by syz.1.66/6234: #0: ffff888033728480 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880626722b0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #1: ffff8880626722b0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline] #1: ffff8880626722b0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4855 1 lock held by syz-executor/7392: #0: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 6 locks held by syz-executor/7423: 2 locks held by syz-executor/7437: #0: ffffffff8e8b8c88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e8b8c88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:847 [inline] #0: ffffffff8e8b8c88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f15e5b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 3 locks held by syz.9.246/7519: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 39 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+0xfaa/0x1000 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 7521 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:policy_nodemask+0x564/0x8e0 mm/mempolicy.c:2277 Code: 40 03 00 eb a8 e8 8c 43 9d ff e9 f2 01 00 00 e8 82 43 9d ff bb 40 00 00 00 48 8b 54 24 08 48 89 d0 48 c1 e8 03 42 0f b6 04 28 <84> c0 0f 85 79 02 00 00 89 1a eb 28 e8 5b 43 9d ff 4c 89 f7 e8 e3 RSP: 0000:ffffc90004b27a00 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888029418000 RDX: ffffc90004b27adc RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90004b27ac8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000006 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffff995fee68 R15: 1ffff92000964f48 FS: 00007f6c3a83f780(0000) GS:ffff888126338000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6c3a77dff8 CR3: 00000000356f8000 CR4: 00000000003526f0 Call Trace: alloc_pages_mpol+0x50/0x380 mm/mempolicy.c:2451 folio_alloc_mpol_noprof mm/mempolicy.c:2509 [inline] vma_alloc_folio_noprof+0xea/0x290 mm/mempolicy.c:2544 folio_prealloc mm/memory.c:-1 [inline] alloc_anon_folio mm/memory.c:5209 [inline] do_anonymous_page mm/memory.c:5266 [inline] do_pte_missing+0x7f9/0x29e0 mm/memory.c:4475 handle_pte_fault mm/memory.c:6317 [inline] __handle_mm_fault mm/memory.c:6455 [inline] handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6624 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f6c3a942e16 Code: 83 0d 00 c3 b8 ea ff ff ff 48 85 ff 74 28 48 85 d2 74 23 49 89 c8 b8 b3 01 00 00 0f 05 48 85 c0 7c 14 74 01 c3 31 ed 4c 89 c7 d2 48 89 c7 b8 3c 00 00 00 0f 05 48 8b 0d af ff 0c 00 f7 d8 64 RSP: 002b:00007f6c3a77e000 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000009000 RCX: 00007f6c3a942e09 RDX: 00007f6c3a92ddd0 RSI: 0000000000000058 RDI: 00007fff86f09780 RBP: 0000000000000000 R08: 00007fff86f09780 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000202 R12: 00007fff86f09aa0 R13: 00007fff86f09780 R14: 0000000000000000 R15: 00007f6c3a92ddd0