INFO: task syz-executor3:7605 blocked for more than 140 seconds. Not tainted 4.19.0-rc8+ #64 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D25400 7605 5590 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x610 kernel/locking/rwsem-xadd.c:286 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0xbe/0x1d0 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:748 [inline] lookup_slow+0x49/0x80 fs/namei.c:1687 walk_component+0x92b/0x25c0 fs/namei.c:1810 lookup_last fs/namei.c:2273 [inline] path_lookupat.isra.43+0x212/0xc00 fs/namei.c:2318 filename_lookup+0x26a/0x520 fs/namei.c:2348 user_path_at_empty+0x40/0x50 fs/namei.c:2608 user_path_at include/linux/namei.h:57 [inline] path_setxattr+0xd6/0x230 fs/xattr.c:464 __do_sys_setxattr fs/xattr.c:484 [inline] __se_sys_setxattr fs/xattr.c:480 [inline] __x64_sys_setxattr+0xc4/0x150 fs/xattr.c:480 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 2a 60 09 <01> 87 01 8b 05 22 60 09 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007f6812875c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000457569 RDX: 00000000200004c0 RSI: 0000000020000300 RDI: 00000000200001c0 RBP: 000000000072c180 R08: 0000000000000001 R09: 0000000000000000 R10: 000000000000000c R11: 0000000000000246 R12: 00007f68128766d4 R13: 00000000004bddbc R14: 00000000004d7140 R15: 00000000ffffffff INFO: task syz-executor3:7606 blocked for more than 140 seconds. Not tainted 4.19.0-rc8+ #64 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D23992 7606 5590 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0xbb9/0x1670 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+0xa5/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:738 [inline] chown_common+0x3a9/0x730 fs/open.c:629 do_fchownat+0x16e/0x250 fs/open.c:662 __do_sys_chown fs/open.c:682 [inline] __se_sys_chown fs/open.c:680 [inline] __x64_sys_chown+0x7b/0xc0 fs/open.c:680 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 2a 60 09 <01> 87 01 8b 05 22 60 09 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007f6812854c78 EFLAGS: 00000246 ORIG_RAX: 000000000000005c RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000140 RBP: 000000000072c220 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f68128556d4 R13: 00000000004c2525 R14: 00000000004cc3a0 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/987: #0: 0000000031b2d61b (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5361: #0: 000000009a93c996 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5484: #0: 00000000d8738364 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d56803c9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5485: #0: 00000000750cd318 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000a785e330 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5486: #0: 00000000b51e2cc6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000036048f47 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5487: #0: 000000008f7382dd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000009cfbf2c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5488: #0: 00000000df948a6c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c7fdb759 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5489: #0: 000000005991313c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c7f97e20 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5490: #0: 00000000f8d3a535 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d1cc73f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor3/7564: #0: 00000000422797e9 (sb_writers#13){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000422797e9 (sb_writers#13){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: chown_common+0x3a9/0x730 fs/open.c:629 1 lock held by syz-executor3/7605: #0: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: inode_lock_shared include/linux/fs.h:748 [inline] #0: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1687 2 locks held by syz-executor3/7606: #0: 00000000422797e9 (sb_writers#13){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000422797e9 (sb_writers#13){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 000000009b8bae94 (&sb->s_type->i_mutex_key#20){++++}, at: chown_common+0x3a9/0x730 fs/open.c:629 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 987 Comm: khungtaskd Not tainted 4.19.0-rc8+ #64 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+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc8+ #64 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_nmi_enter+0x8a/0x1e0 kernel/rcu/tree.c:937 Code: 00 00 00 48 89 45 d0 31 c0 e8 82 5d 23 02 89 c0 48 8d 3c c5 e0 9e 00 89 48 89 fa 48 c1 ea 03 42 80 3c 22 00 0f 85 11 01 00 00 <48> 03 1c c5 e0 9e 00 89 48 b8 00 00 00 00 00 fc ff df 4c 8d 73 08 RSP: 0018:ffff8801daf07c20 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000023980 RCX: ffffffff838d268a RDX: 1ffffffff12013dd RSI: ffffffff838d2698 RDI: ffffffff89009ee8 RBP: ffff8801daf07cb0 R08: ffff8801d9b1e3c0 R09: ffffed003b5e5979 R10: ffffed003b5e5979 R11: ffff8801daf2cbcb R12: dffffc0000000000 R13: 1ffff1003b5e0f85 R14: ffff8801daf07e68 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001c95ec000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_irq_enter+0xce/0x100 kernel/rcu/tree.c:992 irq_enter+0xa/0xe0 kernel/softirq.c:346 scheduler_ipi+0x3d0/0xad0 kernel/sched/core.c:1770 smp_reschedule_interrupt+0x109/0x650 arch/x86/kernel/smp.c:278 reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:888 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57 Code: e9 2c ff ff ff 48 89 c7 48 89 45 d8 e8 f3 e0 11 fa 48 8b 45 d8 e9 ca fe ff ff 48 89 df e8 e2 e0 11 fa eb 82 55 48 89 e5 fb f4 <5d> c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 f4 5d c3 90 90 90 90 90 RSP: 0018:ffff8801d9b2fc30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 1ffff1003b365f8a RCX: 0000000000000000 RDX: 1ffffffff1263e44 RSI: 0000000000000001 RDI: ffffffff8931f220 RBP: ffff8801d9b2fc30 R08: ffff8801d9b1e3c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d9b2fcf0 R13: ffffffff89f3bd60 R14: 0000000000000000 R15: 0000000000000001 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0xbf/0x490 arch/x86/kernel/process.c:498 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:489 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x3db/0x5b0 kernel/sched/idle.c:262 cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368 start_secondary+0x447/0x5f0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243