INFO: task syz-executor.5:15187 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:29800 pid:15187 ppid: 12088 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4526 schedule+0xd0/0x2a0 kernel/sched/core.c:4601 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x163/0x260 kernel/sched/completion.c:138 io_sq_thread_stop fs/io_uring.c:6906 [inline] io_finish_async fs/io_uring.c:6920 [inline] io_sq_offload_create fs/io_uring.c:7595 [inline] io_uring_create fs/io_uring.c:8671 [inline] io_uring_setup+0x1495/0x29a0 fs/io_uring.c:8744 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007ff54c241bf8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 0000000020000180 RCX: 000000000045d5b9 RDX: 0000000020ffc000 RSI: 0000000020000180 RDI: 00000000000043a4 RBP: 000000000118cf98 R08: 0000000020000200 R09: 0000000020000200 R10: 00000000200000c0 R11: 0000000000000206 R12: 0000000020ffc000 R13: 0000000020ffc000 R14: 0000000020000200 R15: 00000000200000c0 INFO: task io_uring-sq:15188 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:io_uring-sq state:D stack:31120 pid:15188 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4526 schedule+0xd0/0x2a0 kernel/sched/core.c:4601 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4660 kthread+0x2ac/0x4a0 kernel/kthread.c:285 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 1 lock held by khungtaskd/1172: #0: ffffffff89c67500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829 1 lock held by in:imklog/6571: #0: ffff88809df933b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 2 locks held by rs:main Q:Reg/6573: #0: ffff8880a1feeb70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 #1: ffff888214624460 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2793 [inline] #1: ffff888214624460 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x54f/0x730 fs/read_write.c:574 2 locks held by agetty/6802: #0: ffff88809ede5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc90000f942e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 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+0x198/0x1fd lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:339 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3905 Comm: systemd-journal Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unwind_next_frame+0x98f/0x1f90 arch/x86/kernel/unwind_orc.c:472 Code: 89 c3 41 83 e3 07 44 38 df 41 0f 9e c3 40 84 ff 40 0f 95 c7 41 84 fb 0f 85 17 13 00 00 83 e0 07 40 38 c6 40 0f 9e c7 40 84 f6 <0f> 95 c0 40 84 c7 0f 85 fe 12 00 00 49 0f bf 00 48 01 d0 48 89 44 RSP: 0018:ffffc900053b7710 EFLAGS: 00000246 RAX: 0000000000000005 RBX: 1ffff92000a76eea RCX: ffffffff8b31a651 RDX: ffffc900053b7b20 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffffffff8b31a64c R09: ffffffff8b31a650 R10: 000000000007201e R11: 0000000000000001 R12: ffffc900053b7830 R13: ffffc900053b781d R14: ffffc900053b7838 R15: ffffc900053b77e8 FS: 00007f52ad4dc8c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f52a9036000 CR3: 0000000093607000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x1b0/0x310 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:666 [inline] tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45 tomoyo_encode2 security/tomoyo/realpath.c:31 [inline] tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x186/0x620 security/tomoyo/realpath.c:288 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x212/0x3f0 security/tomoyo/file.c:822 security_path_truncate+0xcf/0x140 security/security.c:1144 do_sys_ftruncate+0x3f7/0x570 fs/open.c:193 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f52ac79fec7 Code: 73 01 c3 48 8b 0d d1 5f 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 4d 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 5f 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffef7f51e28 EFLAGS: 00000206 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007ffef7f51e60 RCX: 00007f52ac79fec7 RDX: 000055ce41c2b130 RSI: 0000000000800000 RDI: 0000000000000016 RBP: 00007ffef7f51e58 R08: 0000000000000008 R09: 000055ce41c2b45c R10: 000055ce41c2b3e0 R11: 0000000000000206 R12: 000055ce41c2b3e0 R13: 00007ffef7f51f58 R14: 000055ce4073b958 R15: 0005aeb5e823ef03