INFO: task syz.0.914:14345 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00093-gfdf042df0463 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.914 state:D stack:24176 pid:14345 tgid:14344 ppid:13862 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 percpu_rwsem_wait+0x3c2/0x450 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] __sb_start_write include/linux/fs.h:1676 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1812 mnt_want_write+0x3f/0x90 fs/namespace.c:515 open_last_lookups fs/namei.c:3636 [inline] path_openat+0x779/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 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: 0033:0x7f34bbf7def9 RSP: 002b:00007f34bb9ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f34bc135f80 RCX: 00007f34bbf7def9 RDX: 0000000000000042 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f34bbff0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000184 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f34bc135f80 R15: 00007ffd5ce21158 INFO: task syz.0.914:14358 blocked for more than 144 seconds. Not tainted 6.11.0-rc7-syzkaller-00093-gfdf042df0463 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.914 state:D stack:25088 pid:14358 tgid:14344 ppid:13862 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 percpu_rwsem_wait+0x3c2/0x450 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] __sb_start_write include/linux/fs.h:1676 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1812 mnt_want_write+0x3f/0x90 fs/namespace.c:515 filename_create+0x184/0x540 fs/namei.c:3972 do_mkdirat+0xbd/0x3a0 fs/namei.c:4225 __do_sys_mkdirat fs/namei.c:4248 [inline] __se_sys_mkdirat fs/namei.c:4246 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4246 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: 0033:0x7f34bbf7def9 RSP: 002b:00007f34bb9de038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f34bc136058 RCX: 00007f34bbf7def9 RDX: 0000000000000000 RSI: 0000000020000100 RDI: ffffffffffffff9c RBP: 00007f34bbff0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f34bc136058 R15: 00007ffd5ce21158 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 1 lock held by khungtaskd/30: #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 6 locks held by kworker/u8:6/1060: #0: ffff88801b6e3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801b6e3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900042e7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900042e7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fa6d250 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: caif_exit_net+0x6f/0x4a0 net/caif/caif_dev.c:528 #4: ffff888030b2d780 (&caifn->caifdevs.lock){+.+.}-{3:3}, at: caif_exit_net+0x82/0x4a0 net/caif/caif_dev.c:529 #5: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #5: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 2 locks held by dhcpcd/4890: #0: ffff888058704678 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404 #1: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6506 2 locks held by getty/4985: #0: ffff888030ad60a0 (&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+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:12/6236: 1 lock held by syz.1.671/12220: 1 lock held by syz.0.914/14345: #0: ffff888059fe8420 (sb_writers#17){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 1 lock held by syz.0.914/14358: #0: ffff888059fe8420 (sb_writers#17){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 3 locks held by syz.0.966/14744: 1 lock held by syz-executor/15518: 3 locks held by syz-executor/15773: #0: ffff8880358e0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff8880358e0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff8880358e0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fbe5a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fbe5a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2592 3 locks held by syz.0.1095/15857: #0: ffff8880577ccd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff8880577ccd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff8880577cc078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fbe5a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fbe5a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2592 1 lock held by syz-executor/15881: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00093-gfdf042df0463 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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: 14744 Comm: syz.0.966 Not tainted 6.11.0-rc7-syzkaller-00093-gfdf042df0463 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:90 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x2d6/0x2a00 arch/x86/kernel/unwind_orc.c:494 Code: be 92 23 91 48 89 4c 24 18 48 39 c1 0f 83 bd 1d 00 00 4b 8d 0c 64 48 8d 8c 09 5c 29 77 90 48 39 c1 0f 87 a8 1d 00 00 44 89 e7 <44> 89 fe e8 f2 63 52 00 45 39 fc 0f 85 70 01 00 00 e8 24 62 52 00 RSP: 0018:ffffc900097d6bc8 EFLAGS: 00000287 RAX: ffffffff912392be RBX: ffffffff9127bb00 RCX: ffffffff9089ab5e RDX: ffff88802635bc00 RSI: 0000000000010a0f RDI: 00000000000315ab RBP: 0000000000010a0f R08: ffffffff81412994 R09: ffffc900097d6d90 R10: 0000000000000003 R11: ffffffff817f2f30 R12: 00000000000315ab R13: 00000000000ae001 R14: dffffc0000000000 R15: 00000000000315a3 FS: 00007fa16bf7a6c0(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557d2c31c0f8 CR3: 000000006edbe000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2256 [inline] slab_free mm/slub.c:4477 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4552 free_buffer_head+0x54/0x240 fs/buffer.c:3041 try_to_free_buffers+0x311/0x5f0 fs/buffer.c:2982 mapping_evict_folio+0x285/0x5d0 mm/truncate.c:274 mapping_try_invalidate+0x23c/0x4f0 mm/truncate.c:496 drop_pagecache_sb+0x1bc/0x250 fs/drop_caches.c:40 iterate_supers+0xc6/0x190 fs/super.c:934 drop_caches_sysctl_handler+0x8c/0x160 fs/drop_caches.c:64 proc_sys_call_handler+0x551/0x8b0 fs/proc/proc_sysctl.c:590 iter_file_splice_write+0xbd7/0x14e0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11e/0x220 fs/splice.c:1164 splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x28c/0x3e0 fs/splice.c:1233 do_sendfile+0x56d/0xe20 fs/read_write.c:1295 __do_sys_sendfile64 fs/read_write.c:1356 [inline] __se_sys_sendfile64+0x100/0x1e0 fs/read_write.c:1348 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: 0033:0x7fa16b17def9 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:00007fa16bf7a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fa16b335f80 RCX: 00007fa16b17def9 RDX: 00000000200000c0 RSI: 0000000000000007 RDI: 0000000000000008 RBP: 00007fa16b1f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa16b335f80 R15: 00007fffe519b918