NOHZ: local_softirq_pending 08 GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.1:15833 blocked for more than 140 seconds. Not tainted 4.19.122-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28528 15833 6560 0x00000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x896/0xf20 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x176/0x2c0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:660 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x1031/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 08 48 c7 44 24 10 09 00 00 00 e8 02 a1 fa ff 48 8b 44 24 18 48 8b 4c 24 30 48 83 c1 10 48 89 0c 24 48 89 44 24 08 48 c7 44 24 <10> 58 1f 00 00 e8 dd a0 fa ff 48 8b 44 24 18 48 89 44 24 40 48 8b RSP: 002b:00007fbcf9439c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004f8e20 RCX: 000000000045c829 RDX: 0000000000105000 RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000809 R14: 00000000004cac4e R15: 00007fbcf943a6d4 INFO: task syz-executor.1:15874 blocked for more than 140 seconds. Not tainted 4.19.122-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29120 15874 6560 0x00000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x896/0xf20 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x176/0x2c0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:660 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x1031/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 08 48 c7 44 24 10 09 00 00 00 e8 02 a1 fa ff 48 8b 44 24 18 48 8b 4c 24 30 48 83 c1 10 48 89 0c 24 48 89 44 24 08 48 c7 44 24 <10> 58 1f 00 00 e8 dd a0 fa ff 48 8b 44 24 18 48 89 44 24 40 48 8b RSP: 002b:00007fbcf9439c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004f8e20 RCX: 000000000045c829 RDX: 0000000000105000 RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000809 R14: 00000000004cac4e R15: 00007fbcf943a6d4 Showing all locks held in the system: 1 lock held by khungtaskd/1080: #0: 00000000721e28bd (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6138: #0: 00000000802b1a4a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 5 locks held by syz-executor.5/15810: 2 locks held by syz-executor.5/17594: #0: 000000008666aee1 (tty_mutex){+.+.}, at: tty_open_by_driver drivers/tty/tty_io.c:1945 [inline] #0: 000000008666aee1 (tty_mutex){+.+.}, at: tty_open+0x3bf/0xb00 drivers/tty/tty_io.c:2029 #1: 000000003a9be54b (&tty->legacy_mutex){+.+.}, at: tty_lock+0x6a/0xa0 drivers/tty/tty_mutex.c:19 1 lock held by syz-executor.5/17603: #0: 000000008666aee1 (tty_mutex){+.+.}, at: tty_open_by_driver drivers/tty/tty_io.c:1945 [inline] #0: 000000008666aee1 (tty_mutex){+.+.}, at: tty_open+0x3bf/0xb00 drivers/tty/tty_io.c:2029 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1080 Comm: khungtaskd Not tainted 4.19.122-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x962/0xe40 kernel/hung_task.c:287 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15810 Comm: syz-executor.5 Not tainted 4.19.122-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97 Code: 48 c7 c7 00 2d 8e 87 4c 89 25 bc a2 26 0a 41 bc f4 ff ff ff e8 3a 1f eb ff 48 c7 05 a6 a2 26 0a 00 00 00 00 e9 24 ec ff ff 90 <48> 8b 34 24 65 48 8b 04 25 40 ee 01 00 65 8b 15 1c 24 9a 7e 81 e2 RSP: 0018:ffff88804d28ef58 EFLAGS: 00000216 RAX: 0000000000000000 RBX: 0000000000000050 RCX: ffffffff837b773a RDX: 000000000000004a RSI: 0000000000000050 RDI: 0000000000000004 RBP: 000000000000004a R08: ffff8880496940c0 R09: 0000000000000004 R10: ffffed10432e601b R11: ffff8882197300df R12: ffff8880000a004a R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000f33bdada FS: 00007f251d6e1700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c432758000 CR3: 0000000095f4a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: writeb arch/x86/include/asm/io.h:65 [inline] vga16fb_fillrect+0x9c6/0x1960 drivers/video/fbdev/vga16fb.c:923 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x2d8/0x370 drivers/video/fbdev/core/fbcon.c:1342 ypan_up_redraw drivers/video/fbdev/core/fbcon.c:1527 [inline] fbcon_scroll+0x13be/0x3700 drivers/video/fbdev/core/fbcon.c:1905 con_scroll+0x5bb/0x6c0 drivers/tty/vt/vt.c:632 lf+0x262/0x2b0 drivers/tty/vt/vt.c:1479 do_con_trol+0x59b/0x5c00 drivers/tty/vt/vt.c:2147 do_con_write.part.0+0xf55/0x1db0 drivers/tty/vt/vt.c:2798 do_con_write drivers/tty/vt/vt.c:2566 [inline] con_write+0x41/0xe0 drivers/tty/vt/vt.c:3133 do_output_char+0x5dd/0x850 drivers/tty/n_tty.c:445 process_output drivers/tty/n_tty.c:512 [inline] n_tty_write+0x497/0x1080 drivers/tty/n_tty.c:2343 do_tty_write drivers/tty/tty_io.c:960 [inline] tty_write+0x452/0x790 drivers/tty/tty_io.c:1044 __vfs_write+0xf7/0x760 fs/read_write.c:485 __kernel_write+0x109/0x370 fs/read_write.c:506 write_pipe_buf+0x153/0x1e0 fs/splice.c:798 splice_from_pipe_feed fs/splice.c:503 [inline] __splice_from_pipe+0x38f/0x7a0 fs/splice.c:627 splice_from_pipe+0xd9/0x140 fs/splice.c:662 default_file_splice_write+0x37/0x90 fs/splice.c:810 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1025 splice_direct_to_actor+0x33f/0x8d0 fs/splice.c:980 do_splice_direct+0x1a8/0x270 fs/splice.c:1068 do_sendfile+0x549/0xc10 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64 fs/read_write.c:1494 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f251d6e0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00000000004fc2e0 RCX: 000000000045c829 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0800000080004105 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008dc R14: 00000000004cb816 R15: 00007f251d6e16d4