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INFO: task hung in vt_resize (2)

Status: auto-closed as invalid on 2020/09/29 03:27
Subsystems: serial
[Documentation on labels]
First crash: 2092d, last: 2092d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in vt_resize 1 1 2163d 2163d 0/1 auto-closed as invalid on 2020/08/19 20:33
upstream INFO: task hung in vt_resize serial 1 1 2216d 2213d 0/29 auto-closed as invalid on 2020/06/27 10:07
upstream INFO: task hung in vt_resize (3) kernel 1 1 284d 284d 0/29 auto-obsoleted due to no activity on 2025/09/11 01:46
linux-4.14 INFO: task hung in vt_resize 1 1 2276d 2276d 0/1 auto-closed as invalid on 2020/04/28 10:00
linux-4.14 INFO: task hung in vt_resize (2) 1 1 2125d 2125d 0/1 auto-closed as invalid on 2020/09/27 00:31

Sample crash report:
INFO: task syz-executor.5:24829 blocked for more than 143 seconds.
      Not tainted 5.8.0-rc3-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28744 24829   7288 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3453 [inline]
 __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178
 schedule+0xd0/0x2a0 kernel/sched/core.c:4253
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1873
 __down_common kernel/locking/semaphore.c:220 [inline]
 __down+0x183/0x2a0 kernel/locking/semaphore.c:237
 down+0x57/0x80 kernel/locking/semaphore.c:61
 console_lock+0x25/0x80 kernel/printk/printk.c:2309
 vt_resize+0x41/0xe0 drivers/tty/vt/vt.c:1354
 tiocswinsz drivers/tty/tty_io.c:2277 [inline]
 tty_ioctl+0x119a/0x15f0 drivers/tty/tty_io.c:2576
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007ff1e4adfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004eff20 RCX: 000000000045cb29
RDX: 0000000020000140 RSI: 0000000000005414 RDI: 0000000000000003
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005a3 R14: 00000000004c86d5 R15: 00007ff1e4ae06d4

Showing all locks held in the system:
1 lock held by khungtaskd/1142:
 #0: ffffffff89bc1140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779
1 lock held by in:imklog/6508:
 #0: ffff888096fa73b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826
1 lock held by syz-executor.5/24820:

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

NMI backtrace for cpu 1
CPU: 1 PID: 1142 Comm: khungtaskd Not tainted 5.8.0-rc3-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+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd7d/0x1000 kernel/hung_task.c:295
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 24820 Comm: syz-executor.5 Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:62 [inline]
RIP: 0010:bitfill_aligned+0xe6/0x200 drivers/video/fbdev/core/cfbfillrect.c:35
Code: fd e8 2e b5 b1 fd 31 ff 44 89 fe e8 a4 b1 b1 fd 45 85 ff 0f 85 f6 00 00 00 e8 16 b5 b1 fd 44 89 e0 31 d2 bf 07 00 00 00 f7 f5 <41> 89 c4 89 c6 41 89 c7 e8 7d b1 b1 fd 41 83 fc 07 76 5f 4c 89 ed
RSP: 0018:ffffc900016d7708 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 0000000000000000 RCX: ffffc9001419f000
RDX: 0000000000000000 RSI: ffffffff83c2020a RDI: 0000000000000007
RBP: 0000000000000040 R08: 00000000000000c0 R09: 0000000000000040
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000000c0
R13: ffff8880000a0000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007ff1e4b01700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f49ff86eac0 CR3: 00000000a44a0000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 cfb_fillrect+0x40b/0x7b0 drivers/video/fbdev/core/cfbfillrect.c:327
 vga16fb_fillrect+0x683/0x193b drivers/video/fbdev/vga16fb.c:951
 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232
 fbcon_clear_margins+0x1d5/0x230 drivers/video/fbdev/core/fbcon.c:1381
 fbcon_switch+0xb6e/0x16c0 drivers/video/fbdev/core/fbcon.c:2363
 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015
 vc_do_resize+0x110e/0x13f0 drivers/tty/vt/vt.c:1314
 vt_resize+0xa3/0xe0 drivers/tty/vt/vt.c:1355
 tiocswinsz drivers/tty/tty_io.c:2277 [inline]
 tty_ioctl+0x119a/0x15f0 drivers/tty/tty_io.c:2576
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007ff1e4b00c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004eff20 RCX: 000000000045cb29
RDX: 0000000020000140 RSI: 0000000000005414 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005a3 R14: 00000000004c86d5 R15: 00007ff1e4b016d4

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/07/01 03:17 upstream 9ebcfadb0610 917afeaa .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.