INFO: task syz.2.174:7670 blocked for more than 143 seconds. Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.174 state:D stack:27032 pid:7670 tgid:7649 ppid:5840 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 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 inode_lock_shared include/linux/fs.h:887 [inline] lookup_slow+0x45/0x70 fs/namei.c:1809 walk_component fs/namei.c:2114 [inline] link_path_walk+0x99b/0xea0 fs/namei.c:2479 path_parentat fs/namei.c:2683 [inline] __filename_parentat+0x2a7/0x740 fs/namei.c:2707 filename_parentat fs/namei.c:2725 [inline] do_renameat2+0x3b8/0x13f0 fs/namei.c:5138 __do_sys_rename fs/namei.c:5273 [inline] __se_sys_rename fs/namei.c:5271 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:5271 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: 0033:0x7f172718d169 RSP: 002b:00007f1727fa5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007f17273a6080 RCX: 00007f172718d169 RDX: 0000000000000000 RSI: 0000400000000100 RDI: 0000400000000080 RBP: 00007f172720e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f17273a6080 R15: 00007ffe7c8ec408 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:2/35: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000ab7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ab7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 4 locks held by kworker/u8:3/55: #0: ffff888020ac2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888020ac2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000bf7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000bf7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff88807ac900e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff8880757fb918 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x24a/0x590 fs/jfs/inode.c:102 5 locks held by kworker/u8:4/76: #0: ffff88801bef3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc900021bfc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900021bfc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8feb6b90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606 #3: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x880 net/core/dev.c:12417 #4: ffffffff8eb3e478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #4: ffffffff8eb3e478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996 3 locks held by kworker/u8:6/1319: 1 lock held by dhcpcd/5491: #0: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x241/0x360 net/ipv6/addrconf.c:4795 2 locks held by getty/5585: #0: ffff88803112a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 4 locks held by syz.2.174/7650: 1 lock held by syz.2.174/7670: #0: ffff8880757fbcc8 (&type->i_mutex_dir_key#11){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:887 [inline] #0: ffff8880757fbcc8 (&type->i_mutex_dir_key#11){++++}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1809 7 locks held by syz-executor/9806: #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3035 [inline] #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd10 fs/read_write.c:675 #1: ffff888052f79c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888144b01698 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f769a68 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88805b3550e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff88805b3550e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88805b3550e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff88805b356250 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xa4/0x620 drivers/net/netdevsim/netdev.c:1016 4 locks held by syz-executor/9816: #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3035 [inline] #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd10 fs/read_write.c:675 #1: ffff8880323fe888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888144b015a8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f769a68 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 4 locks held by syz-executor/9872: #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3035 [inline] #0: ffff888030eda420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd10 fs/read_write.c:675 #1: ffff888024c13c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888144b01698 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f769a68 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 2 locks held by syz.1.368/9939: #0: ffff88807ac900e0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807ac900e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff8880256107d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880256107d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819 1 lock held by syz-executor/10160: #0: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fec33c8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bc0 net/ipv4/devinet.c:987 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5186 Comm: klogd Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0033:0x7fb46c1949cd Code: 48 83 c7 61 48 01 f8 eb b2 0f 1f 40 00 48 83 cf 1f c5 fd 6f 57 01 c5 fd 74 da c5 f5 74 d2 c5 ed eb db c5 fd d7 c3 85 c0 75 a3 fd 6f 57 21 c5 fd 74 da c5 f5 74 d2 c5 ed eb db c5 fd d7 c3 85 RSP: 002b:00007ffd2275a378 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007fb46c2f278a RCX: 0000000000000000 RDX: 000000056370cb74 RSI: 000000000000000a RDI: 00007fb46c2f279f RBP: 0000000000000000 R08: 0000000000000007 R09: 3b5ac2e8faa2e503 R10: 0000000000004000 R11: 0000000000000007 R12: 00007fb46c2f24a0 R13: 00007fb46c2e2212 R14: 00007fb46c2f278b R15: 00007fb46c2f278b FS: 00007fb46bff2380 GS: 0000000000000000