INFO: task hung in con_font_op

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: bfb9e5c0 Linux 4.14.159
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14a79b46e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=8b2dd838381e2c80
dashboard link: https://syzkaller.appspot.com/bug?extid=75cb72f274763394c73a
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+75cb72...@syzkaller.appspotmail.com

kobject: 'kvm' (ffff888219463290): fill_kobj_path: path
= '/devices/virtual/misc/kvm'
kobject: 'kvm' (ffff888219463290): kobject_uevent_env
kobject: 'kvm' (ffff888219463290): fill_kobj_path: path
= '/devices/virtual/misc/kvm'
kobject: 'kvm' (ffff888219463290): kobject_uevent_env
kobject: 'kvm' (ffff888219463290): fill_kobj_path: path
= '/devices/virtual/misc/kvm'
INFO: task syz-executor.3:12331 blocked for more than 140 seconds.
Not tainted 4.14.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D28024 12331 12303 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2808 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
schedule+0x92/0x1c0 kernel/sched/core.c:3428
schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723
__down_common kernel/locking/semaphore.c:221 [inline]
__down+0x160/0x290 kernel/locking/semaphore.c:238
down+0x64/0x90 kernel/locking/semaphore.c:62
console_lock+0x28/0x80 kernel/printk/printk.c:2216
con_font_get drivers/tty/vt/vt.c:4074 [inline]
con_font_op+0x130/0x1060 drivers/tty/vt/vt.c:4229
vt_ioctl+0xb80/0x2170 drivers/tty/vt/vt_ioctl.c:927
tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a919
RSP: 002b:00007ff54341dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919
RDX: 0000000020000200 RSI: 0000000000004b60 RDI: 0000000000000008
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff54341e6d4
R13: 00000000004c3552 R14: 00000000004d89d0 R15: 00000000ffffffff
INFO: task syz-executor.3:12335 blocked for more than 140 seconds.
Not tainted 4.14.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D29328 12335 12303 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2808 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
schedule+0x92/0x1c0 kernel/sched/core.c:3428
schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723
__down_common kernel/locking/semaphore.c:221 [inline]
__down+0x160/0x290 kernel/locking/semaphore.c:238
down+0x64/0x90 kernel/locking/semaphore.c:62
console_lock+0x28/0x80 kernel/printk/printk.c:2216
con_font_get drivers/tty/vt/vt.c:4074 [inline]
con_font_op+0x130/0x1060 drivers/tty/vt/vt.c:4229
vt_ioctl+0xb80/0x2170 drivers/tty/vt/vt_ioctl.c:927
tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a919
RSP: 002b:00007ff5433dac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919
RDX: 0000000020000200 RSI: 0000000000004b60 RDI: 0000000000000006
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff5433db6d4
R13: 00000000004c3552 R14: 00000000004d89d0 R15: 00000000ffffffff

Showing all locks held in the system:
1 lock held by khungtaskd/1044:
#0: (tasklist_lock){.+.+}, at: [<ffffffff8148c8d8>]
debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/6937:
#0: (&f->f_pos_lock){+.+.}, at: [<ffffffff81966a5b>]
__fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/7060:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7061:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7062:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7063:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7064:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7065:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7066:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff8664f9c3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83491bf6>]
n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156

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

NMI backtrace for cpu 1
CPU: 1 PID: 1044 Comm: khungtaskd Not tainted 4.14.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x142/0x197 lib/dump_stack.c:58
nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
watchdog+0x5e7/0xb90 kernel/hung_task.c:274
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 12317 Comm: syz-executor.1 Not tainted 4.14.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
task: ffff888059e44240 task.stack: ffff8880801e8000
RIP: 0010:__sanitizer_cov_trace_pc+0x51/0x60 kernel/kcov.c:93
RSP: 0018:ffff8880801ef260 EFLAGS: 00000246
RAX: 0000000000040000 RBX: 0000000000000240 RCX: ffffc90005a84000
RDX: 0000000000040000 RSI: ffffffff8328b10f RDI: ffff8880a5852cc0
RBP: ffff8880801ef260 R08: 0000000000000240 R09: 0000000000000040
R10: ffffed1014bf5783 R11: ffff8880a5fabc1f R12: 0000000000000000
R13: 0000000000000000 R14: ffff8880000a0000 R15: 0000000000000000
FS: 00007f4f7f109700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c422d055f0 CR3: 000000005c6dd000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:43 [inline]
bitfill_aligned+0x2f/0x190 drivers/video/fbdev/core/cfbfillrect.c:35
cfb_fillrect+0x3d0/0x720 drivers/video/fbdev/core/cfbfillrect.c:327
vga16fb_fillrect+0x618/0x1880 drivers/video/fbdev/vga16fb.c:951
bit_clear_margins+0x2d5/0x4f0 drivers/video/fbdev/core/bitblit.c:232
fbcon_clear_margins+0x292/0x320 drivers/video/fbdev/core/fbcon.c:1317
fbcon_switch+0xd38/0x1820 drivers/video/fbdev/core/fbcon.c:2299
redraw_screen+0x335/0x7c0 drivers/tty/vt/vt.c:688
fbcon_modechanged+0x59e/0x880 drivers/video/fbdev/core/fbcon.c:2946
fbcon_event_notify+0x11f/0x17af drivers/video/fbdev/core/fbcon.c:3299
notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93
__blocking_notifier_call_chain kernel/notifier.c:317 [inline]
__blocking_notifier_call_chain kernel/notifier.c:304 [inline]
blocking_notifier_call_chain kernel/notifier.c:328 [inline]
blocking_notifier_call_chain+0x80/0xa0 kernel/notifier.c:325
fb_notifier_call_chain+0x25/0x30 drivers/video/fbdev/core/fb_notify.c:45
fb_set_var+0xb09/0xcf0 drivers/video/fbdev/core/fbmem.c:1054
do_fb_ioctl+0x3cc/0x940 drivers/video/fbdev/core/fbmem.c:1127
fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1242
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a919
RSP: 002b:00007f4f7f108c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4f7f1096d4
R13: 00000000004c310d R14: 00000000004d8478 R15: 00000000ffffffff
Code: 74 01 c3 55 48 89 e5 48 8b 75 08 48 8b 88 58 13 00 00 8b 80 54 13 00
00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 <5d> c3 0f 1f
00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 672481c2 Linux 4.19.91
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=162b8069e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=445a712574d168a6
dashboard link: https://syzkaller.appspot.com/bug?extid=4133d0ca51bd00722409

compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+4133d0...@syzkaller.appspotmail.com

netlink: 6 bytes leftover after parsing attributes in process
`syz-executor.4'.
kobject: 'loop2' (00000000992636ae): kobject_uevent_env
kobject: 'loop2' (00000000992636ae): fill_kobj_path: path
= '/devices/virtual/block/loop2'
kobject: 'loop4' (000000004532e9bc): kobject_uevent_env
kobject: 'loop4' (000000004532e9bc): fill_kobj_path: path
= '/devices/virtual/block/loop4'
INFO: task syz-executor.0:29352 blocked for more than 140 seconds.
Not tainted 4.19.91-syzkaller #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

syz-executor.0 D29096 29352 25360 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
schedule+0x92/0x1c0 kernel/sched/core.c:3559
schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1782
__down_common kernel/locking/semaphore.c:221 [inline]
__down+0x176/0x2c0 kernel/locking/semaphore.c:238
down+0x64/0x90 kernel/locking/semaphore.c:62
console_lock+0x29/0x80 kernel/printk/printk.c:2244
con_font_set drivers/tty/vt/vt.c:4488 [inline]
con_font_op+0xd29/0x1250 drivers/tty/vt/vt.c:4557
do_fontx_ioctl drivers/tty/vt/vt_ioctl.c:244 [inline]
vt_ioctl+0x35a/0x2530 drivers/tty/vt/vt_ioctl.c:930
tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a919
Code: Bad RIP value.
RSP: 002b:00007f3a00dedc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010

RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919

RDX: 0000000020000000 RSI: 0000000000004b6c RDI: 0000000000000004

RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3a00dee6d4
R13: 00000000004c4847 R14: 00000000004da0d0 R15: 00000000ffffffff

Showing all locks held in the system:

1 lock held by khungtaskd/1068:
#0: 00000000975d7b8f (rcu_read_lock){....}, at:
debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438
1 lock held by rsyslogd/7499:
#0: 000000002436d80a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110
fs/file.c:767
2 locks held by getty/7621:
#0: 0000000056abe8a4 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000c0ddf0cb (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7622:
#0: 00000000d30789ab (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 000000004b2a5b88 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7623:
#0: 0000000034ddc47a (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 0000000009d5b626 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7624:
#0: 00000000e31c0de3 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000ac2b6620 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7625:
#0: 000000009913dd7f (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000ce9fdfe9 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7626:
#0: 00000000e4eb88e7 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 000000001f54c31e (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7627:
#0: 00000000a9f68414 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 000000005a908f9f (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
1 lock held by syz-executor.0/29310:

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

NMI backtrace for cpu 0
CPU: 0 PID: 1068 Comm: khungtaskd Not tainted 4.19.91-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+0x197/0x210 lib/dump_stack.c:118
nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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+0x354/0x420 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:

NMI backtrace for cpu 1

CPU: 1 PID: 29310 Comm: syz-executor.0 Not tainted 4.19.91-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011

RIP: 0010:__sanitizer_cov_trace_pc+0x3b/0x50 kernel/kcov.c:106
Code: 65 8b 15 78 a9 96 7e 81 e2 00 01 1f 00 75 2b 8b 90 d0 12 00 00 83 fa
02 75 20 48 8b 88 d8 12 00 00 8b 80 d4 12 00 00 48 8b 11 <48> 83 c2 01 48
39 d0 76 07 48 89 34 d1 48 89 11 5d c3 0f 1f 00 65
RSP: 0018:ffff888075c9f618 EFLAGS: 00000246
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000a2a8000
RDX: 000000000003ffff RSI: ffffffff8383a186 RDI: 0000000000001400
RBP: ffff888075c9f618 R08: ffff8880a1140200 R09: 0000000000000040
R10: 000000004057d457 R11: 0000000000000000 R12: 0000000000001400
R13: 0000000000000040 R14: ffff8880000a0000 R15: 0000000000000000
FS: 00007f3a00e30700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000000c433237130 CR3: 00000000424e0000 CR4: 00000000001426e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:55 [inline]
bitfill_aligned+0xc6/0x210 drivers/video/fbdev/core/cfbfillrect.c:35
cfb_fillrect+0x423/0x7c0 drivers/video/fbdev/core/cfbfillrect.c:327
vga16fb_fillrect+0x6ce/0x19b0 drivers/video/fbdev/vga16fb.c:951
bit_clear_margins+0x30b/0x530 drivers/video/fbdev/core/bitblit.c:232
fbcon_clear_margins+0x2e3/0x370 drivers/video/fbdev/core/fbcon.c:1339
fbcon_do_set_font+0x730/0xa40 drivers/video/fbdev/core/fbcon.c:2582
fbcon_set_font+0x72e/0x860 drivers/video/fbdev/core/fbcon.c:2674
con_font_set drivers/tty/vt/vt.c:4492 [inline]
con_font_op+0xe18/0x1250 drivers/tty/vt/vt.c:4557
do_fontx_ioctl drivers/tty/vt/vt_ioctl.c:244 [inline]
vt_ioctl+0x35a/0x2530 drivers/tty/vt/vt_ioctl.c:930
tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a919
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:00007f3a00e2fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010

RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919

RDX: 0000000020000000 RSI: 0000000000004b6c RDI: 0000000000000004

RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3a00e306d4
R13: 00000000004c4847 R14: 00000000004da0d0 R15: 00000000ffffffff

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.

[syzbot]