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INFO: task hung in vt_ioctl

Status: auto-closed as invalid on 2020/05/23 20:53
Subsystems: serial
[Documentation on labels]
First crash: 1801d, last: 1801d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vt_ioctl (4) serial 1 496d 496d 0/28 auto-obsoleted due to no activity on 2023/12/19 05:20
linux-4.19 INFO: task hung in vt_ioctl 1 1707d 1707d 0/1 auto-closed as invalid on 2020/09/24 20:12
upstream INFO: task hung in vt_ioctl (3) serial 1 676d 676d 0/28 auto-obsoleted due to no activity on 2023/06/22 09:16
upstream INFO: task hung in vt_ioctl (2) serial 2 1670d 1709d 0/28 auto-closed as invalid on 2020/10/01 08:58

Sample crash report:
INFO: task syz-executor.4:15613 blocked for more than 143 seconds.
      Not tainted 5.6.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D28264 15613      1 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3380 [inline]
 __schedule+0x87f/0xcd0 kernel/sched/core.c:4080
 schedule+0x188/0x210 kernel/sched/core.c:4154
 schedule_timeout+0x46/0x240 kernel/time/timer.c:1871
 __down_common+0x28c/0x510 kernel/locking/semaphore.c:220
 __down+0x18/0x20 kernel/locking/semaphore.c:237
 down+0x6b/0xb0 kernel/locking/semaphore.c:61
 console_lock+0x28/0x70 kernel/printk/printk.c:2289
 vt_ioctl+0x12c4/0x3a30 drivers/tty/vt/vt_ioctl.c:833
 tty_ioctl+0xee6/0x15c0 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl fs/ioctl.c:763 [inline]
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl+0x113/0x190 fs/ioctl.c:770
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:770
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c429
Code: 00 00 00 48 8d 44 24 30 48 89 44 24 08 48 c7 44 24 10 00 00 00 00 c7 44 24 18 08 00 00 00 e8 9e 44 00 00 eb 42 90 c7 04 24 02 <00> 00 00 48 8d 44 24 30 48 89 44 24 08 48 c7 44 24 10 00 00 00 00
RSP: 002b:00007f969b4c3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f969b4c46d4 RCX: 000000000045c429
RDX: 0000000020000140 RSI: 0000000000005609 RDI: 0000000000000003
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000572 R14: 00000000004c7c1e R15: 000000000076bf2c
INFO: task syz-executor.4:15725 blocked for more than 143 seconds.
      Not tainted 5.6.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D29400 15725      1 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3380 [inline]
 __schedule+0x87f/0xcd0 kernel/sched/core.c:4080
 schedule+0x188/0x210 kernel/sched/core.c:4154
 schedule_timeout+0x46/0x240 kernel/time/timer.c:1871
 __down_common+0x28c/0x510 kernel/locking/semaphore.c:220
 __down+0x18/0x20 kernel/locking/semaphore.c:237
 down+0x6b/0xb0 kernel/locking/semaphore.c:61
 console_lock+0x28/0x70 kernel/printk/printk.c:2289
 vt_ioctl+0x12c4/0x3a30 drivers/tty/vt/vt_ioctl.c:833
 tty_ioctl+0xee6/0x15c0 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl fs/ioctl.c:763 [inline]
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl+0x113/0x190 fs/ioctl.c:770
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:770
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c429
Code: 00 00 00 48 8d 44 24 30 48 89 44 24 08 48 c7 44 24 10 00 00 00 00 c7 44 24 18 08 00 00 00 e8 9e 44 00 00 eb 42 90 c7 04 24 02 <00> 00 00 48 8d 44 24 30 48 89 44 24 08 48 c7 44 24 10 00 00 00 00
RSP: 002b:00007f969b481c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f969b4826d4 RCX: 000000000045c429
RDX: 0000000020000140 RSI: 0000000000005609 RDI: 0000000000000003
RBP: 000000000076c060 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000572 R14: 00000000004c7c1e R15: 000000000076c06c

Showing all locks held in the system:
1 lock held by khungtaskd/1044:
 #0: ffffffff892d9908 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207
1 lock held by rsyslogd/8757:
 #0: ffff88808ec8a5e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x279/0x310 fs/file.c:821
2 locks held by getty/8848:
 #0: ffff888091947090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc9000185b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/8849:
 #0: ffff88809b66f090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc9000187b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/8850:
 #0: ffff88809dd01090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc9000186b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/8851:
 #0: ffff88809f217090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc900017fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/8852:
 #0: ffff88808d8a4090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc9000188b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/8853:
 #0: ffff88809246c090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc900017cb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
2 locks held by getty/14280:
 #0: ffff8880a7d6b090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc90001f9b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.2/15609:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1044 Comm: khungtaskd Not tainted 5.6.0-rc2-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+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaa/0x190 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x16f/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xd40/0xd60 kernel/hung_task.c:289
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15609 Comm: syz-executor.2 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__writeq arch/x86/include/asm/io.h:98 [inline]
RIP: 0010:bitfill_aligned+0x140/0x200 drivers/video/fbdev/core/cfbfillrect.c:64
Code: 48 8b 45 b8 31 d2 f7 75 d0 89 c3 bf 07 00 00 00 89 c6 e8 d3 7d a6 fd 83 fb 07 76 4c 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 <4d> 89 34 24 4d 89 74 24 08 4d 89 74 24 10 4d 89 74 24 18 4d 89 74
RSP: 0018:ffffc90004bef710 EFLAGS: 00000212
RAX: ffff8880466604c0 RBX: 0000000000000050 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000050 RDI: 0000000000000007
RBP: ffffc90004bef760 R08: ffffffff83d08eed R09: 0000000000000040
R10: ffff8880466604c0 R11: 0000000000000002 R12: ffff8880000a0000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffffffffff
FS:  00007fda7ad59700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0192d0448 CR3: 00000000a7fd7000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 cfb_fillrect+0x57b/0x7a0 drivers/video/fbdev/core/cfbfillrect.c:327
 vga16fb_fillrect+0x642/0x1470 drivers/video/fbdev/vga16fb.c:951
 bit_clear_margins+0x368/0x620 drivers/video/fbdev/core/bitblit.c:232
 fbcon_clear_margins drivers/video/fbdev/core/fbcon.c:1379 [inline]
 fbcon_do_set_font+0xcfc/0x1240 drivers/video/fbdev/core/fbcon.c:2611
 fbcon_set_font+0x7a0/0x990 drivers/video/fbdev/core/fbcon.c:2703
 con_font_set drivers/tty/vt/vt.c:4549 [inline]
 con_font_op+0xeb9/0x1620 drivers/tty/vt/vt.c:4614
 vt_ioctl+0xa9b/0x3a30 drivers/tty/vt/vt_ioctl.c:918
 tty_ioctl+0xee6/0x15c0 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl fs/ioctl.c:763 [inline]
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl+0x113/0x190 fs/ioctl.c:770
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:770
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c429
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fda7ad58c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fda7ad596d4 RCX: 000000000045c429
RDX: 0000000020000140 RSI: 0000000000004b61 RDI: 0000000000000003
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000572 R14: 00000000004c7c1e R15: 000000000076bf2c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/02/23 20:51 upstream 0a115e5f23b9 2c36e7a7 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.