INFO: task syz-executor1:14719 blocked for more than 140 seconds. Not tainted 4.20.0+ #167 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D25376 14719 7986 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 __rwsem_down_write_failed_common+0xbbc/0x15e0 kernel/locking/rwsem-xadd.c:577 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 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_nested+0xa9/0x130 kernel/locking/rwsem.c:195 inode_lock_nested include/linux/fs.h:792 [inline] filename_create+0x1b2/0x5b0 fs/namei.c:3635 user_path_create fs/namei.c:3693 [inline] do_mknodat+0x1c2/0x530 fs/namei.c:3754 __do_sys_mknod fs/namei.c:3794 [inline] __se_sys_mknod fs/namei.c:3792 [inline] __x64_sys_mknod+0x7b/0xb0 fs/namei.c:3792 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457759 Code: Bad RIP value. RSP: 002b:00007fb5480bcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457759 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000020000440 RBP: 000000000073c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb5480bd6d4 R13: 00000000004c323a R14: 00000000004d5c10 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1025: #0: 00000000b7527fd4 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 3 locks held by rs:main Q:Reg/7842: #0: 000000009384d13c (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 000000003b1a9e0f (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2810 [inline] #1: 000000003b1a9e0f (sb_writers#3){.+.+}, at: vfs_write+0x42a/0x560 fs/read_write.c:548 #2: 000000001ce164fd (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1124 [inline] #2: 000000001ce164fd (&rq->lock){-.-.}, at: __schedule+0x236/0x1ed0 kernel/sched/core.c:3410 1 lock held by rsyslogd/7844: #0: 0000000078c1c9c3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/7934: #0: 0000000023fe53cc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b967f537 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7935: #0: 00000000c21bd7bc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001a4b80f5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7936: #0: 0000000077190070 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001c60af91 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7937: #0: 000000005e678200 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000057704bca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7938: #0: 0000000013f8b7ff (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008e4f1247 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7939: #0: 0000000045b987d5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000138df81c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/7940: #0: 00000000c74aad90 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000006c505e86 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 4 locks held by syz-executor1/14714: 2 locks held by syz-executor1/14719: #0: 00000000399f81aa (sb_writers#18){.+.+}, at: sb_start_write include/linux/fs.h:1597 [inline] #0: 00000000399f81aa (sb_writers#18){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000c0a9dadf (&sb->s_type->i_mutex_key#26/1){+.+.}, at: inode_lock_nested include/linux/fs.h:792 [inline] #1: 00000000c0a9dadf (&sb->s_type->i_mutex_key#26/1){+.+.}, at: filename_create+0x1b2/0x5b0 fs/namei.c:3635 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1025 Comm: khungtaskd Not tainted 4.20.0+ #167 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+0x1d3/0x2c6 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1c2/0x22c 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:205 [inline] watchdog+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.225 msecs NMI backtrace for cpu 1 CPU: 1 PID: 14714 Comm: syz-executor1 Not tainted 4.20.0+ #167 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:put_page_testzero include/linux/mm.h:519 [inline] RIP: 0010:put_page include/linux/mm.h:962 [inline] RIP: 0010:grow_dev_page fs/buffer.c:982 [inline] RIP: 0010:grow_buffers fs/buffer.c:1016 [inline] RIP: 0010:__getblk_slow fs/buffer.c:1043 [inline] RIP: 0010:__getblk_gfp+0x973/0xd50 fs/buffer.c:1320 Code: 0f 8e 55 02 00 00 49 c1 ee 03 89 85 58 fe ff ff 89 c6 31 ff 43 c6 04 3e f8 89 85 c0 fd ff ff e8 d3 e1 9f ff 8b 85 c0 fd ff ff <85> c0 0f 84 6f 01 00 00 e8 b0 e0 9f ff be 04 00 00 00 48 89 df e8 RSP: 0018:ffff88817e2fee28 EFLAGS: 00000297 RAX: 0000000000000003 RBX: ffffea00070d31b4 RCX: ffffffff81de780d RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffff88817e2ff0a0 R08: ffff8881ca5940c0 R09: fffff94000e1a636 R10: fffff94000e1a636 R11: ffffea00070d31b7 R12: 0000000000000001 R13: ffffea00070d3180 R14: 1ffff1102fc5fddf R15: dffffc0000000000 FS: 00007fb548120700(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001b967a000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __bread_gfp+0x2d/0x300 fs/buffer.c:1354 sb_bread include/linux/buffer_head.h:307 [inline] fat__get_entry+0x5a6/0xa40 fs/fat/dir.c:101 fat_get_entry fs/fat/dir.c:129 [inline] fat_search_long+0x33b/0x1570 fs/fat/dir.c:479 vfat_find+0x16d/0x1a0 fs/fat/namei_vfat.c:697 vfat_lookup+0x107/0x640 fs/fat/namei_vfat.c:711 lookup_open+0x72e/0x1b90 fs/namei.c:3213 do_last fs/namei.c:3324 [inline] path_openat+0x15e4/0x5160 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 ksys_open include/linux/syscalls.h:1279 [inline] __do_sys_creat fs/open.c:1121 [inline] __se_sys_creat fs/open.c:1119 [inline] __x64_sys_creat+0x61/0x80 fs/open.c:1119 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457759 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb54811fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457759 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb5481206d4 R13: 00000000004bde7d R14: 00000000004ce020 R15: 00000000ffffffff