INFO: task hung in do_fb_ioctl
7 views
Skip to first unread message
syzbot
Dec 3, 2019, 12:09:10 AM12/3/19
to syzkaller...@googlegroups.com
Hello,
syzbot found the following crash on:
HEAD commit: fbc5fe7a Linux 4.14.157
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10350f36e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d49d9f4045dcfa5d
dashboard link: https://syzkaller.appspot.com/bug?extid=cf6a6e77b141849d26a6
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16673edae00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=126c7aeae00000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+cf6a6e...@syzkaller.appspotmail.com
audit: type=1400 audit(1575345751.415:36): avc: denied { map } for
pid=7071 comm="syz-executor260" path="/root/syz-executor260914159"
dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
INFO: task syz-executor260:7079 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7079 7075 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7080 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7080 7073 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7081 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7081 7076 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_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
fb_open+0xb7/0x420 drivers/video/fbdev/core/fbmem.c:1468
chrdev_open+0x207/0x590 fs/char_dev.c:423
do_dentry_open+0x73b/0xeb0 fs/open.c:777
vfs_open+0x105/0x220 fs/open.c:891
do_last fs/namei.c:3425 [inline]
path_openat+0x8bd/0x3f70 fs/namei.c:3566
do_filp_open+0x18e/0x250 fs/namei.c:3600
do_sys_open+0x2c5/0x430 fs/open.c:1084
SYSC_openat fs/open.c:1111 [inline]
SyS_openat+0x30/0x40 fs/open.c:1105
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000000000000 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7082 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7082 7074 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_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
fb_open+0xb7/0x420 drivers/video/fbdev/core/fbmem.c:1468
chrdev_open+0x207/0x590 fs/char_dev.c:423
do_dentry_open+0x73b/0xeb0 fs/open.c:777
vfs_open+0x105/0x220 fs/open.c:891
do_last fs/namei.c:3425 [inline]
path_openat+0x8bd/0x3f70 fs/namei.c:3566
do_filp_open+0x18e/0x250 fs/namei.c:3600
do_sys_open+0x2c5/0x430 fs/open.c:1084
SYSC_openat fs/open.c:1111 [inline]
SyS_openat+0x30/0x40 fs/open.c:1105
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000000000000 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7083 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7083 7072 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/1042:
#0: (tasklist_lock){.+.+}, at: [<ffffffff8148a428>]
debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/6923:
#0: (&f->f_pos_lock){+.+.}, at: [<ffffffff8196407b>]
__fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/7046:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7047:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7048:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7049:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7050:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7051:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7052:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
1 lock held by syz-executor260/7081:
#0: (&fb_info->lock){+.+.}, at: [<ffffffff83246fd7>] fb_open+0xb7/0x420
drivers/video/fbdev/core/fbmem.c:1468
1 lock held by syz-executor260/7082:
#0: (&fb_info->lock){+.+.}, at: [<ffffffff83246fd7>] fb_open+0xb7/0x420
drivers/video/fbdev/core/fbmem.c:1468
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 4.14.157-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: 7078 Comm: syz-executor260 Not tainted 4.14.157-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
task: ffff888071cac300 task.stack: ffff8880985b0000
RIP: 0010:cfb_fillrect+0x3a2/0x720
drivers/video/fbdev/core/cfbfillrect.c:325
RSP: 0018:ffff8880985b72c0 EFLAGS: 00000297
RAX: ffff888071cac300 RBX: ffff8880a5831540 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000040
RBP: ffff8880985b7320 R08: 0000000000001400 R09: 0000000000000040
R10: ffffed1014bea1d3 R11: ffff8880a5f50e9f R12: ffff8880000a0000
R13: 0000000000000000 R14: 0000000000001400 R15: 00000000332ec410
FS: 00000000025c8880(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000840 CR3: 000000007e9b3000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
Code: bc f8 48 8b 45 a0 89 7d c0 44 0f af 75 a8 48 c1 e8 03 48 01 d0 48 89
45 b8 44 89 f8 4d 89 ef 41 89 c5 e8 32 b1 34 fe 0f b6 4d c0 <44> 89 e8 41
83 e5 3f 6a 00 41 b9 40 00 00 00 45 89 f0 44 89 ea
---
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 can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
syzbot found the following crash on:
HEAD commit: fbc5fe7a Linux 4.14.157
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10350f36e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d49d9f4045dcfa5d
dashboard link: https://syzkaller.appspot.com/bug?extid=cf6a6e77b141849d26a6
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16673edae00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=126c7aeae00000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+cf6a6e...@syzkaller.appspotmail.com
audit: type=1400 audit(1575345751.415:36): avc: denied { map } for
pid=7071 comm="syz-executor260" path="/root/syz-executor260914159"
dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
INFO: task syz-executor260:7079 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7079 7075 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7080 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7080 7073 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7081 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7081 7076 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_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
fb_open+0xb7/0x420 drivers/video/fbdev/core/fbmem.c:1468
chrdev_open+0x207/0x590 fs/char_dev.c:423
do_dentry_open+0x73b/0xeb0 fs/open.c:777
vfs_open+0x105/0x220 fs/open.c:891
do_last fs/namei.c:3425 [inline]
path_openat+0x8bd/0x3f70 fs/namei.c:3566
do_filp_open+0x18e/0x250 fs/namei.c:3600
do_sys_open+0x2c5/0x430 fs/open.c:1084
SYSC_openat fs/open.c:1111 [inline]
SyS_openat+0x30/0x40 fs/open.c:1105
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000000000000 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7082 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7082 7074 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_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
fb_open+0xb7/0x420 drivers/video/fbdev/core/fbmem.c:1468
chrdev_open+0x207/0x590 fs/char_dev.c:423
do_dentry_open+0x73b/0xeb0 fs/open.c:777
vfs_open+0x105/0x220 fs/open.c:891
do_last fs/namei.c:3425 [inline]
path_openat+0x8bd/0x3f70 fs/namei.c:3566
do_filp_open+0x18e/0x250 fs/namei.c:3600
do_sys_open+0x2c5/0x430 fs/open.c:1084
SYSC_openat fs/open.c:1111 [inline]
SyS_openat+0x30/0x40 fs/open.c:1105
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000000000000 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor260:7083 blocked for more than 140 seconds.
Not tainted 4.14.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor260 D28528 7083 7072 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
do_fb_ioctl+0x36a/0x940 drivers/video/fbdev/core/fbmem.c:1121
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/1042:
#0: (tasklist_lock){.+.+}, at: [<ffffffff8148a428>]
debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/6923:
#0: (&f->f_pos_lock){+.+.}, at: [<ffffffff8196407b>]
__fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/7046:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7047:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7048:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7049:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7050:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7051:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/7052:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff86614193>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8348e086>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
1 lock held by syz-executor260/7081:
#0: (&fb_info->lock){+.+.}, at: [<ffffffff83246fd7>] fb_open+0xb7/0x420
drivers/video/fbdev/core/fbmem.c:1468
1 lock held by syz-executor260/7082:
#0: (&fb_info->lock){+.+.}, at: [<ffffffff83246fd7>] fb_open+0xb7/0x420
drivers/video/fbdev/core/fbmem.c:1468
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 4.14.157-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: 7078 Comm: syz-executor260 Not tainted 4.14.157-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
task: ffff888071cac300 task.stack: ffff8880985b0000
RIP: 0010:cfb_fillrect+0x3a2/0x720
drivers/video/fbdev/core/cfbfillrect.c:325
RSP: 0018:ffff8880985b72c0 EFLAGS: 00000297
RAX: ffff888071cac300 RBX: ffff8880a5831540 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000040
RBP: ffff8880985b7320 R08: 0000000000001400 R09: 0000000000000040
R10: ffffed1014bea1d3 R11: ffff8880a5f50e9f R12: ffff8880000a0000
R13: 0000000000000000 R14: 0000000000001400 R15: 00000000332ec410
FS: 00000000025c8880(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000840 CR3: 000000007e9b3000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
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: 0033:0x441419
RSP: 002b:00007ffedc91df68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441419
RDX: 0000000020000180 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402190
R13: 0000000000402220 R14: 0000000000000000 R15: 0000000000000000
Code: bc f8 48 8b 45 a0 89 7d c0 44 0f af 75 a8 48 c1 e8 03 48 01 d0 48 89
45 b8 44 89 f8 4d 89 ef 41 89 c5 e8 32 b1 34 fe 0f b6 4d c0 <44> 89 e8 41
83 e5 3f 6a 00 41 b9 40 00 00 00 45 89 f0 44 89 ea
---
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 can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
Reply all
Reply to author
Forward
0 new messages