INFO: task syz-executor0:20955 blocked for more than 140 seconds. Not tainted 5.0.0-rc1-next-20190111 #10 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D24728 20955 7915 0x00000004 Call Trace: context_switch kernel/sched/core.c:2834 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3475 schedule+0xfe/0x350 kernel/sched/core.c:3519 __rwsem_down_write_failed_common+0xa4d/0x1620 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+0xa5/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:766 [inline] process_measurement+0xbf6/0x1be0 security/integrity/ima/ima_main.c:207 ima_file_check+0xe3/0x130 security/integrity/ima/ima_main.c:393 do_last fs/namei.c:3422 [inline] path_openat+0x14d7/0x5660 fs/namei.c:3534 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 ksys_open include/linux/syscalls.h:1301 [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+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: Bad RIP value. RSP: 002b:00007f3d2cfd7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3d2cfd86d4 R13: 00000000004be42a R14: 00000000004ce8b8 R15: 00000000ffffffff Showing all locks held in the system: 5 locks held by kworker/u4:0/7: 1 lock held by khungtaskd/1040: #0: 000000001e9eb07d (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4408 1 lock held by rsyslogd/7789: #0: 0000000058f24e3e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:796 2 locks held by getty/7879: #0: 0000000069659122 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ef9aa52f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7880: #0: 00000000237b39b8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000017adbdf2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7881: #0: 00000000100ace4a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000029d2f1c6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7882: #0: 000000005ae4846a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000003e1e9d53 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7883: #0: 0000000051831092 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000054912036 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7884: #0: 00000000f4a785ff (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000408980fd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7885: #0: 0000000032cdaa8c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000161dd45 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 1 lock held by syz-executor5/13665: #0: 00000000e6d2d714 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1407 [inline] #0: 00000000e6d2d714 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file.isra.0+0x45d/0x2700 fs/exec.c:1750 2 locks held by syz-executor0/20955: #0: 000000008632216c (sb_writers#18){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 000000008632216c (sb_writers#18){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 0000000015485b20 (&sb->s_type->i_mutex_key#26){++++}, at: inode_lock include/linux/fs.h:766 [inline] #1: 0000000015485b20 (&sb->s_type->i_mutex_key#26){++++}, at: process_measurement+0xbf6/0x1be0 security/integrity/ima/ima_main.c:207 8 locks held by syz-executor0/20968: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc1-next-20190111 #10 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+0x1db/0x2d0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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+0xbbb/0x1170 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:247 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.0.0-rc1-next-20190111 #10 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:67 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x50 kernel/kcov.c:101 Code: 85 68 fe ff ff e9 85 df ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 48 8b 75 08 65 48 8b 04 25 40 ee 01 00 <65> 8b 15 18 c1 7f 7e 81 e2 00 01 1f 00 75 2b 8b 90 e0 12 00 00 83 RSP: 0018:ffff8880a946e9b0 EFLAGS: 00000086 RAX: ffff8880a94601c0 RBX: ffff88809f4eef18 RCX: ffffffff81e3f49c RDX: 0000000000000000 RSI: ffffffff8392d83c RDI: ffffffff888209a0 RBP: ffff8880a946e9b0 R08: ffff8880a94601c0 R09: fffff94000477a0f R10: fffff94000477a0e R11: ffffea00023bd077 R12: ffffffff888209a0 R13: 0000000000000195 R14: ffffffff88562ea0 R15: 000000000000000f FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c41f01b166 CR3: 0000000092b2e000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_preemption_disabled+0x1c/0x290 lib/smp_processor_id.c:13 __this_cpu_preempt_check+0x1d/0x30 lib/smp_processor_id.c:62 lookup_bh_lru fs/buffer.c:1298 [inline] __find_get_block+0x16a/0xf20 fs/buffer.c:1327 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3c2/0x1140 fs/buffer.c:1357 __bread_gfp+0x2f/0x300 fs/buffer.c:1391 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x33a/0xb70 fs/fat/inode.c:859 fat_write_inode+0x96/0x190 fs/fat/inode.c:908 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xef1/0x1620 fs/fs-writeback.c:1375 writeback_sb_inodes+0x762/0x1260 fs/fs-writeback.c:1580 __writeback_inodes_wb+0x16d/0x3d0 fs/fs-writeback.c:1649 wb_writeback+0xa2d/0xf70 fs/fs-writeback.c:1758 wb_check_old_data_flush fs/fs-writeback.c:1860 [inline] wb_do_writeback fs/fs-writeback.c:1913 [inline] wb_workfn+0xf7f/0x16f0 fs/fs-writeback.c:1942 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:247 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352