NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
INFO: task syz-executor.5:26906 blocked for more than 140 seconds.
Not tainted 4.19.118-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5 D28688 26906 6955 0x00000004
Call Trace:
schedule+0x8d/0x1b0 kernel/sched/core.c:3559
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457
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:00007f01ca967c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00000000004f7140 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000079a R14: 00000000004ca4cf R15: 00007f01ca9686d4
Showing all locks held in the system:
1 lock held by khungtaskd/1080:
#0: 0000000034321fd0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/6125:
#0: 0000000053cbd5ef (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767
2 locks held by agetty/6123:
#0: 0000000074bed395 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: 00000000fd23bcff (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154
3 locks held by syz-executor.5/26884:
1 lock held by syz-executor.5/26906:
#0: 000000007a89c97d (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 1080 Comm: khungtaskd Not tainted 4.19.118-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: 26884 Comm: syz-executor.5 Not tainted 4.19.118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:write_comp_data+0x68/0x70 kernel/kcov.c:146
Code: 00 00 4e 8d 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 <c3> 0f 1f 80 00 00 00 00 48 8b 0c 24 40 0f b6 d6 40 0f b6 f7 31 ff
RSP: 0018:ffff8880470872c0 EFLAGS: 00000297
RAX: 0000000000000002 RBX: 0000000000000050 RCX: ffffffff837a2f0a
RDX: 0000000000000009 RSI: 0000000000000050 RDI: 0000000000000004
RBP: 0000000000000009 R08: ffff88809b2ec400 R09: ffffed1014aa7844
R10: ffffed1014aa7843 R11: ffff8880a553c21f R12: ffff8880000a0009
R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000f1543aa7
FS: 00007f01ca989700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89a0b41000 CR3: 0000000043457000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
vga16fb_fillrect+0x9da/0x1960 drivers/video/fbdev/vga16fb.c:922
bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232
fbcon_clear_margins+0x2d8/0x370 drivers/video/fbdev/core/fbcon.c:1342
fbcon_switch+0xe0f/0x1970 drivers/video/fbdev/core/fbcon.c:2324
redraw_screen+0x37d/0x870 drivers/tty/vt/vt.c:1009
fbcon_modechanged+0x5eb/0x8f0 drivers/video/fbdev/core/fbcon.c:2972
fbcon_event_notify+0x1b2/0x1d54 drivers/video/fbdev/core/fbcon.c:3347
notifier_call_chain+0xc0/0x230 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+0x85/0xa0 kernel/notifier.c:325
fb_set_var+0xc39/0xe00 drivers/video/fbdev/core/fbmem.c:1042
do_fb_ioctl+0x450/0x9c0 drivers/video/fbdev/core/fbmem.c:1115
fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
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:00007f01ca988c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e46c0 RCX: 000000000045c829
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000002f0 R14: 00000000004c5497 R15: 00007f01ca9896d4