Hello, syzbot found the following issue on: HEAD commit: 9b62e02e6336 Merge tag 'mm-hotfixes-stable-2024-05-25-09-1.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16cb0eec980000 kernel config: https://syzkaller.appspot.com/x/.config?x=3e73beba72b96506 dashboard link: https://syzkaller.appspot.com/bug?extid=7f3bbe59e8dd2328a990 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/61b507f6e56c/disk-9b62e02e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6991f1313243/vmlinux-9b62e02e.xz kernel image: https://storage.googleapis.com/syzbot-assets/65f88b96d046/bzImage-9b62e02e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7f3bbe59e8dd2328a990@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor.2:9163 blocked for more than 143 seconds. Not tainted 6.9.0-syzkaller-12393-g9b62e02e6336 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27024 pid:9163 tgid:9163 ppid:8496 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2557 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3de/0x5f0 kernel/sched/completion.c:116 __vhost_worker_flush+0x1aa/0x1e0 drivers/vhost/vhost.c:288 vhost_worker_flush drivers/vhost/vhost.c:295 [inline] vhost_dev_flush+0xad/0x120 drivers/vhost/vhost.c:305 vhost_vsock_flush drivers/vhost/vsock.c:694 [inline] vhost_vsock_dev_release+0x1a5/0x400 drivers/vhost/vsock.c:746 __fput+0x408/0xbb0 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1555 [inline] __se_sys_close fs/open.c:1540 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1540 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f910027bdda RSP: 002b:00007ffc83a68930 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f910027bdda RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f91003ad980 R08: 0000001b2ec20000 R09: 00000000000003f6 R10: 000000008ae9c606 R11: 0000000000000293 R12: 0000000000056292 R13: 00007f91003abf8c R14: 00007ffc83a68a30 R15: 0000000000000032 </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by kworker/u8:3/51: #0: ffff8880196fe948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc90000bc7d80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 3 locks held by kworker/u8:6/1041: #0: ffff888029f54148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc90004507d80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 #2: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcf/0x1500 net/ipv6/addrconf.c:4193 2 locks held by kworker/u8:8/1261: 2 locks held by getty/4844: #0: ffff88802b1860a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 2 locks held by syz-fuzzer/7666: 3 locks held by syz-executor.1/9466: #0: ffff88802ce84d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:554 #1: ffff88802ce84078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x339/0x1100 net/bluetooth/hci_sync.c:5050 #2: ffffffff8dbbd078 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:323 1 lock held by syz-executor.3/11000: #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x250 drivers/net/tun.c:3500 1 lock held by syz-executor.3/11005: #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x250 drivers/net/tun.c:3500 1 lock held by syz-executor.4/11002: #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x250 drivers/net/tun.c:3500 1 lock held by syz-executor.1/11013: #0: ffffffff8f74afa8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x4fc/0x4770 drivers/net/tun.c:3110 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
