INFO: task syz.0.322:7111 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-04003-gfc1dc0d50780 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.322 state:D stack:27360 pid:7111 tgid:7103 ppid:5224 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 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:1715 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1851 mnt_want_write+0x3f/0x90 fs/namespace.c:515 vfs_truncate+0xd3/0x3b0 fs/open.c:84 do_sys_truncate+0xdb/0x190 fs/open.c:134 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: 0033:0x7fadf057def9 RSP: 002b:00007fadf140d038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007fadf0736130 RCX: 00007fadf057def9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020001980 RBP: 00007fadf05f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fadf0736130 R15: 00007fff576acbe8 INFO: task kmmpd-loop0:7109 blocked for more than 145 seconds. Not tainted 6.11.0-syzkaller-04003-gfc1dc0d50780 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kmmpd-loop0 state:D stack:26856 pid:7109 tgid:7109 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 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:1715 [inline] sb_start_write include/linux/fs.h:1851 [inline] write_mmp_block+0x2f2/0x3a0 fs/ext4/mmp.c:66 kmmpd+0x26d/0xaa0 fs/ext4/mmp.c:246 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e938a60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938a60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/1:2/934: 2 locks held by getty/4980: #0: ffff8880303910a0 (&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 3 locks held by kworker/0:4/5287: #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900030bfd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900030bfd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff8880338c1240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 8 locks held by kworker/0:8/5381: 2 locks held by kworker/u8:12/5726: #0: ffff88801ffaa148 ( (wq_completion)iou_exit){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3206 [inline] , at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900042c7d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900042c7d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 2 locks held by kworker/u8:19/6042: #0: ffff88801ffaa148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801ffaa148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004347d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004347d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 1 lock held by syz.0.322/7111: #0: ffff88802edf8420 (sb_writers#4){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 1 lock held by kmmpd-loop0/7109: #0: ffff88802edf8420 (sb_writers#4){++++}-{0:0}, at: kmmpd+0x26d/0xaa0 fs/ext4/mmp.c:246 1 lock held by syz-executor/8138: #0: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:965 1 lock held by syz.1.555/8457: #0: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:965 2 locks held by syz.0.556/8461: #0: ffff88807e90a008 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff88807e90a008 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88807e90a008 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 #1: ffff888077f7a258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1609 [inline] #1: ffff888077f7a258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1ec/0x880 net/can/bcm.c:1575 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-04003-gfc1dc0d50780 #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+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111