INFO: task syz-executor.3:18787 blocked for more than 140 seconds. Not tainted 5.0.0-rc6+ #70 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D24000 18787 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2844 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3485 schedule+0x92/0x180 kernel/sched/core.c:3529 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:584 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:613 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+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:757 [inline] vfs_unlink+0xd1/0x500 fs/namei.c:3990 do_unlinkat+0x3f7/0x6d0 fs/namei.c:4062 __do_sys_unlink fs/namei.c:4109 [inline] __se_sys_unlink fs/namei.c:4107 [inline] __x64_sys_unlink+0x42/0x50 fs/namei.c:4107 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457b87 Code: Bad RIP value. RSP: 002b:00007ffc55861248 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000457b87 RDX: 00007ffc55861260 RSI: 00007ffc55861260 RDI: 00007ffc558612f0 RBP: 00000000000000d2 R08: 0000000000000000 R09: 0000000000000012 R10: 000000000000000d R11: 0000000000000246 R12: 00007ffc55862380 R13: 000000000101b940 R14: 0000000000000000 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 00000000339d2dda (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4389 2 locks held by rs:main Q:Reg/7470: #0: 000000000271076f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:795 #1: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2816 [inline] #1: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: vfs_write+0x429/0x580 fs/read_write.c:548 1 lock held by rsyslogd/7472: #0: 000000009c0cf45b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:795 2 locks held by getty/7563: #0: 00000000e78fdb13 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004bfeedb9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7564: #0: 000000004fdd77fb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000077034d88 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7565: #0: 000000009ea506ea (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000afd5c56a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7566: #0: 000000004834b7af (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e493816b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7567: #0: 0000000052b32681 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000087bba7f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7568: #0: 00000000c7d1e2bc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000cbf268cd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7569: #0: 0000000047530e19 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000076c9a9a9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 3 locks held by syz-executor.3/18787: #0: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1603 [inline] #0: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:357 #1: 00000000befed25d (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:792 [inline] #1: 00000000befed25d (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x29f/0x6d0 fs/namei.c:4048 #2: 000000002ae38fad (&sb->s_type->i_mutex_key#10){+.+.}, at: inode_lock include/linux/fs.h:757 [inline] #2: 000000002ae38fad (&sb->s_type->i_mutex_key#10){+.+.}, at: vfs_unlink+0xd1/0x500 fs/namei.c:3990 3 locks held by syz-executor.3/19576: #0: 000000001ee16b6b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:795 #1: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2816 [inline] #1: 000000007b1f1fd6 (sb_writers#3){.+.+}, at: vfs_write+0x429/0x580 fs/read_write.c:548 #2: 000000002ae38fad (&sb->s_type->i_mutex_key#10){+.+.}, at: inode_trylock include/linux/fs.h:777 [inline] #2: 000000002ae38fad (&sb->s_type->i_mutex_key#10){+.+.}, at: ext4_file_write_iter+0x250/0x1160 fs/ext4/file.c:232 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc6+ #70 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+0x172/0x1f0 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+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3868 Comm: udevd Not tainted 5.0.0-rc6+ #70 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x26/0x50 kernel/kcov.c:101 Code: 90 90 90 90 55 48 89 e5 48 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 98 0c 92 7e 81 e2 00 01 1f 00 75 2b 8b 90 d8 12 00 00 <83> fa 02 75 20 48 8b 88 e0 12 00 00 8b 80 dc 12 00 00 48 8b 11 48 RSP: 0018:ffff88809821fed0 EFLAGS: 00000046 RAX: ffff888098216300 RBX: 0000000000000000 RCX: ffffffff81754530 RDX: 0000000000000000 RSI: ffffffff81754556 RDI: 0000000000000005 RBP: ffff88809821fed0 R08: ffff888098216300 R09: ffffed1012fbc349 R10: ffffed1012fbc348 R11: ffff888097de1a47 R12: ffff88809821ff58 R13: ffffffff88928200 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f77c43ea7a0(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000098e93000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_off+0x76/0x220 kernel/trace/trace_preemptirq.c:40 syscall_return_slowpath arch/x86/entry/common.c:267 [inline] do_syscall_64+0x213/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f77c3afe943 Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24 RSP: 002b:00007ffe118e73b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: 0000000000000001 RBX: 0000000000000bb8 RCX: 00007f77c3afe943 RDX: 0000000000000008 RSI: 00007ffe118e74b0 RDI: 000000000000000a RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00000000006a8420 R15: 00000000006a0250