INFO: task syz.3.271:8290 blocked for more than 143 seconds. Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.271 state:D stack:23520 pid:8290 tgid:8271 ppid:7580 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/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_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:850 [inline] filename_create+0x260/0x540 fs/namei.c:4026 do_mkdirat+0xbd/0x3a0 fs/namei.c:4272 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 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: 0033:0x7ffbe957cfb7 RSP: 002b:00007ffbea35ee68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007ffbea35eef0 RCX: 00007ffbe957cfb7 RDX: 00000000000001ff RSI: 0000000020000040 RDI: 00000000ffffff9c RBP: 0000000020000000 R08: 00000000200000c0 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000020000040 R13: 00007ffbea35eeb0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 3 locks held by kworker/u8:7/2954: #0: ffff88814d84c948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814d84c948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000b9bfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000b9bfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 4 locks held by udevd/5204: #0: ffff88807c747c30 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb4/0xd70 fs/seq_file.c:182 #1: ffff88802df26c88 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff88807ba8a5a8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff88807c2400e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88807c2400e8 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2736 2 locks held by getty/5588: #0: ffff8880315040a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.3.271/8273: 1 lock held by syz.3.271/8290: #0: ffff8880780a0180 (&type->i_mutex_dir_key#25/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #0: ffff8880780a0180 (&type->i_mutex_dir_key#25/1){+.+.}-{3:3}, at: filename_create+0x260/0x540 fs/namei.c:4026 7 locks held by syz-executor/9497: #0: ffff88807c420420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff88807c420420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:679 #1: ffff888027856c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888027df72d8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55f288 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 #4: ffff88807c2400e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88807c2400e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #5: ffff88807c247250 (&devlink->lock_key#20){+.+.}-{3:3}, at: nsim_drv_probe+0xcb/0xb80 drivers/net/netdevsim/dev.c:1537 #6: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: fib_seq_sum+0x31/0x290 net/core/fib_notifier.c:46 2 locks held by syz-executor/9501: #0: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 #1: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by syz.6.430/9819: #0: ffff88805c8280e0 (&type->s_umount_key#58/1){+.+.}-{3:3}, at: alloc_super+0x221/0x9d0 fs/super.c:344 #1: ffffffff8e93d200 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4562 1 lock held by syz.5.431/9826: 2 locks held by cmp/9862: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #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: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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8273 Comm: syz.3.271 Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x11/0x90 kernel/kcov.c:300 Code: 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 65 48 8b 14 25 80 d7 03 00 <65> 8b 05 c0 fa 6e 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 5b 83 RSP: 0018:ffffc900046278d8 EFLAGS: 00000246 RAX: 00000000001ecc01 RBX: 0000000000000000 RCX: ffffffff8220975f RDX: ffff88807aca0000 RSI: 0000000000000000 RDI: 0000000000000002 RBP: ffffc90004627a30 R08: ffffffff82209779 R09: 1ffff11006f9953f R10: dffffc0000000000 R11: ffffed1006f99540 R12: ffff888037cca9f8 R13: 00000000001ecc62 R14: 000000000008aaf8 R15: ffffea0001277701 FS: 00007ffbea3806c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faced90c440 CR3: 000000005981a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: _test_bit_acquire include/asm-generic/bitops/instrumented-non-atomic.h:154 [inline] buffer_uptodate include/linux/buffer_head.h:171 [inline] block_read_full_folio+0x349/0xcd0 fs/buffer.c:2392 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3825 read_mapping_folio include/linux/pagemap.h:1011 [inline] dir_get_folio fs/sysv/dir.c:64 [inline] sysv_find_entry+0x16a/0x4b0 fs/sysv/dir.c:154 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 lookup_one_qstr_excl+0x11f/0x260 fs/namei.c:1633 filename_create+0x297/0x540 fs/namei.c:4027 do_mkdirat+0xbd/0x3a0 fs/namei.c:4272 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 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: 0033:0x7ffbe957e719 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:00007ffbea380038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007ffbe9736058 RCX: 00007ffbe957e719 RDX: 0000000000000000 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 00007ffbe95f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffbe9736058 R15: 00007ffc87030d78