INFO: task syz-executor.0:8964 blocked for more than 140 seconds. Not tainted 4.19.78 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27664 8964 8225 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:747 [inline] vfs_setxattr+0x98/0x100 fs/xattr.c:218 setxattr+0x26f/0x380 fs/xattr.c:450 path_setxattr+0x197/0x1b0 fs/xattr.c:469 __do_sys_lsetxattr fs/xattr.c:491 [inline] __se_sys_lsetxattr fs/xattr.c:487 [inline] __x64_sys_lsetxattr+0xc1/0x150 fs/xattr.c:487 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 Code: Bad RIP value. RSP: 002b:00007fe21c2ebc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459a59 RDX: 0000000020000380 RSI: 00000000200002c0 RDI: 0000000020000280 RBP: 000000000075bf20 R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000015 R11: 0000000000000246 R12: 00007fe21c2ec6d4 R13: 00000000004c608d R14: 00000000004dae90 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1038: #0: 00000000ca0c769a (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/8064: #0: 00000000c233bc1e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/8186: #0: 000000000ab82d05 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000aa5e85b3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8187: #0: 000000008587f9e3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000003a8f288 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8188: #0: 0000000065f31396 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000009a39af16 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8189: #0: 000000000943372e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000b0a70aee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8190: #0: 00000000d9e46aca (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003d6cd755 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8191: #0: 00000000cbb035d7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000396098f1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/8192: #0: 00000000f4e67529 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a8fc465b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 3 locks held by kworker/u4:7/8507: #0: 00000000ed673766 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1821 [inline] #0: 00000000ed673766 (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1dc0 kernel/sched/core.c:3453 #1: 00000000c8bb8cba ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 #2: 00000000291e5dc2 (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:938 2 locks held by syz-executor.0/8964: #0: 000000000d79a320 (sb_writers#16){.+.+}, at: sb_start_write include/linux/fs.h:1578 [inline] #0: 000000000d79a320 (sb_writers#16){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000ed5c1d79 (&sb->s_type->i_mutex_key#22){+.+.}, at: inode_lock include/linux/fs.h:747 [inline] #1: 00000000ed5c1d79 (&sb->s_type->i_mutex_key#22){+.+.}, at: vfs_setxattr+0x98/0x100 fs/xattr.c:218 2 locks held by syz-executor.0/8968: #0: 000000000d79a320 (sb_writers#16){.+.+}, at: sb_start_write include/linux/fs.h:1578 [inline] #0: 000000000d79a320 (sb_writers#16){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000ed5c1d79 (&sb->s_type->i_mutex_key#22){+.+.}, at: inode_lock include/linux/fs.h:747 [inline] #1: 00000000ed5c1d79 (&sb->s_type->i_mutex_key#22){+.+.}, at: utimes_common.isra.0+0x2e8/0x600 fs/utimes.c:90 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1038 Comm: khungtaskd Not tainted 4.19.78 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60