INFO: task syz-executor4:15777 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #176 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D22760 15777 4400 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 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+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:715 [inline] vfs_setxattr+0x96/0x100 fs/xattr.c:219 setxattr+0x2ea/0x450 fs/xattr.c:451 path_setxattr+0x1e3/0x230 fs/xattr.c:470 __do_sys_lsetxattr fs/xattr.c:492 [inline] __se_sys_lsetxattr fs/xattr.c:488 [inline] __x64_sys_lsetxattr+0xc1/0x150 fs/xattr.c:488 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456b29 Code: 42 08 84 00 48 83 c0 58 48 89 04 24 e8 00 8b fb ff 48 8b 6c 24 08 48 83 c4 10 c3 e8 91 33 00 00 eb bf cc cc cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 2b RSP: 002b:00007ff157717c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007ff1577186d4 RCX: 0000000000456b29 RDX: 0000000020000080 RSI: 0000000020000040 RDI: 0000000020000000 RBP: 0000000000930280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000009 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d19a0 R14: 00000000004c722f R15: 0000000000000003 INFO: task syz-executor4:15837 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #176 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24744 15837 4400 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 request_wait_answer+0x4c8/0x920 fs/fuse/dev.c:463 __fuse_request_send+0x12a/0x1d0 fs/fuse/dev.c:483 fuse_request_send+0x62/0xa0 fs/fuse/dev.c:496 fuse_simple_request+0x33d/0x730 fs/fuse/dev.c:554 fuse_setxattr+0x3df/0x650 fs/fuse/xattr.c:37 fuse_xattr_set+0x3b/0x70 fs/fuse/xattr.c:192 __vfs_setxattr+0x124/0x190 fs/xattr.c:150 __vfs_setxattr_noperm+0x11d/0x410 fs/xattr.c:181 vfs_setxattr+0xd8/0x100 fs/xattr.c:224 setxattr+0x2ea/0x450 fs/xattr.c:451 path_setxattr+0x1e3/0x230 fs/xattr.c:470 __do_sys_lsetxattr fs/xattr.c:492 [inline] __se_sys_lsetxattr fs/xattr.c:488 [inline] __x64_sys_lsetxattr+0xc1/0x150 fs/xattr.c:488 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456b29 Code: 42 08 84 00 48 83 c0 58 48 89 04 24 e8 00 8b fb ff 48 8b 6c 24 08 48 83 c4 10 c3 e8 91 33 00 00 eb bf cc cc cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 2b RSP: 002b:00007ff1576d5c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007ff1576d66d4 RCX: 0000000000456b29 RDX: 0000000020000240 RSI: 0000000020faffe7 RDI: 0000000020000200 RBP: 00000000009303c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000014 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d19a0 R14: 00000000004c722f R15: 0000000000000005 Showing all locks held in the system: 1 lock held by khungtaskd/774: #0: 00000000f35fac88 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4260: 2 locks held by getty/4350: #0: 0000000083fcfa33 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000601f52e4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4351: #0: 00000000b78784a7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000e4dab3b8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4352: #0: 0000000051e8ab04 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000004aa51ac0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4353: #0: 00000000056262a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000007b501ad2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4354: #0: 000000001e81733f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a7efc8e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4355: #0: 0000000036998813 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000dd1a7c35 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4356: #0: 00000000893aa4e5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000008f1c97b3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor4/15777: #0: 000000001ee40034 (sb_writers#19){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001ee40034 (sb_writers#19){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 00000000c16944f7 (&type->i_mutex_dir_key#5){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 00000000c16944f7 (&type->i_mutex_dir_key#5){++++}, at: vfs_setxattr+0x96/0x100 fs/xattr.c:219 2 locks held by syz-executor4/15837: #0: 000000001ee40034 (sb_writers#19){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001ee40034 (sb_writers#19){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 00000000c16944f7 (&type->i_mutex_dir_key#5){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 00000000c16944f7 (&type->i_mutex_dir_key#5){++++}, at: vfs_setxattr+0x96/0x100 fs/xattr.c:219 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 774 Comm: khungtaskd Not tainted 4.18.0-rc7+ #176 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 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:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54