INFO: task syz-executor4:9599 blocked for more than 120 seconds. Not tainted 4.17.0-rc3+ #36 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D20392 9599 4593 0x00000004 Call Trace: context_switch kernel/sched/core.c:2848 [inline] __schedule+0x801/0x1e30 kernel/sched/core.c:3490 schedule+0xef/0x430 kernel/sched/core.c:3549 __rwsem_down_write_failed_common+0x919/0x15d0 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+0xa2/0x120 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:713 [inline] ext4_file_write_iter+0x303/0x1420 fs/ext4/file.c:235 call_write_iter include/linux/fs.h:1784 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x64d/0x960 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_pwrite64+0x174/0x1a0 fs/read_write.c:652 __do_sys_pwrite64 fs/read_write.c:662 [inline] __se_sys_pwrite64 fs/read_write.c:659 [inline] __x64_sys_pwrite64+0x97/0xf0 fs/read_write.c:659 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455979 RSP: 002b:00007f9966448c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f99664496d4 RCX: 0000000000455979 RDX: 000000007e39d7f0 RSI: 0000000020000000 RDI: 0000000000000014 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000004d2 R14: 00000000006fb450 R15: 0000000000000000 Showing all locks held in the system: 2 locks held by khungtaskd/892: #0: 00000000a327422a (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 00000000a327422a (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249 #1: 000000006ac4652a (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470 2 locks held by getty/4517: #0: 000000006226c432 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000011818b9b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4518: #0: 000000004ece233d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000001a207854 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4519: #0: 00000000cfe6a8f6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000aec0bd4b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4520: #0: 00000000acce626b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000028af0e0c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4521: #0: 00000000a35a889c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000091d6649a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4522: #0: 00000000978c6904 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000018a94478 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/25579: #0: 0000000017c5a368 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000002f355d6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by syz-executor4/9599: #0: 00000000560b168a (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2718 [inline] #0: 00000000560b168a (sb_writers#4){.+.+}, at: vfs_write+0x452/0x560 fs/read_write.c:548 #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:713 [inline] #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x303/0x1420 fs/ext4/file.c:235 2 locks held by syz-executor2/9654: #0: 00000000560b168a (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2718 [inline] #0: 00000000560b168a (sb_writers#4){.+.+}, at: vfs_writev+0x293/0x330 fs/read_write.c:1003 #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:713 [inline] #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x303/0x1420 fs/ext4/file.c:235 3 locks held by syz-executor2/9656: #0: 000000000f96ff50 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766 #1: 00000000560b168a (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2718 [inline] #1: 00000000560b168a (sb_writers#4){.+.+}, at: vfs_writev+0x293/0x330 fs/read_write.c:1003 #2: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:713 [inline] #2: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x303/0x1420 fs/ext4/file.c:235 2 locks held by syz-executor2/9657: #0: 00000000560b168a (sb_writers#4){.+.+}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000560b168a (sb_writers#4){.+.+}, at: do_sys_ftruncate+0x290/0x560 fs/open.c:200 #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:713 [inline] #1: 000000001f46dc22 (&sb->s_type->i_mutex_key#10){++++}, at: do_truncate+0x197/0x2a0 fs/open.c:61 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 892 Comm: khungtaskd Not tainted 4.17.0-rc3+ #36 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+0x1b9/0x294 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_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0xc10/0xf60 kernel/hung_task.c:249 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9628 Comm: syz-executor2 Not tainted 4.17.0-rc3+ #36 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x1/0x50 kernel/kcov.c:94 RSP: 0018:ffff88018b8f6c70 EFLAGS: 00000286 RAX: 0000000000000002 RBX: ffff8801d4f3ab78 RCX: ffffffff8768d06f RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: ffff88018b8f6f20 R08: ffff8801b1d902c0 R09: ffffed003b5c46c2 R10: ffffed003b5c46c2 R11: ffff8801dae23613 R12: ffffed003171edb7 R13: 0000000000000031 R14: 0000000000000000 R15: ffff8801d4f3a9c0 FS: 00007f605caa9700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000018bec8000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_get_entries+0x858/0x1020 mm/filemap.c:1636 pagevec_lookup_entries+0x3a/0x80 mm/swap.c:947 truncate_inode_pages_range+0x36c/0x25a0 mm/truncate.c:331 truncate_inode_pages mm/truncate.c:478 [inline] truncate_pagecache+0x66/0x90 mm/truncate.c:801 ext4_setattr+0x1bfb/0x2ac0 fs/ext4/inode.c:5530 notify_change+0xbef/0x10c0 fs/attr.c:313 do_truncate+0x1a4/0x2a0 fs/open.c:63 do_sys_ftruncate+0x492/0x560 fs/open.c:205 __do_sys_ftruncate fs/open.c:215 [inline] __se_sys_ftruncate fs/open.c:213 [inline] __x64_sys_ftruncate+0x59/0x80 fs/open.c:213 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455979 RSP: 002b:00007f605caa8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007f605caa96d4 RCX: 0000000000455979 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000017 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000000a2 R14: 00000000006f4fd0 R15: 0000000000000000 Code: 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 55 <65> 48 8b 04 25 c0 ed 01 00 65 8b 15 0f b0 88 7e 48 89 e5 81 e2 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.159 msecs