syzbot


INFO: task hung in paste_selection (2)

Status: auto-closed as invalid on 2020/11/12 23:24
Reported-by: syzbot+e01bfca8f0f2d65ece4c@syzkaller.appspotmail.com
First crash: 713d, last: 713d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in paste_selection C done 10 855d 930d 1/1 fixed on 2020/03/26 13:10
upstream INFO: task hung in paste_selection (2) C inconclusive error 6 182d 314d 0/22 upstream: reported C repro on 2021/08/19 03:38
upstream INFO: task hung in paste_selection C inconclusive done 8 871d 936d 17/22 fixed on 2020/04/15 17:19
linux-4.14 INFO: task hung in paste_selection (3) 1 521d 521d 0/1 auto-closed as invalid on 2021/05/24 08:55
linux-4.14 INFO: task hung in paste_selection C done 8 855d 930d 1/1 fixed on 2020/03/27 08:38

Sample crash report:
NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
NOHZ: local_softirq_pending 08
INFO: task syz-executor.3:8678 blocked for more than 140 seconds.
      Not tainted 4.14.184-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29568  8678   6350 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x8a6/0x1d70 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_timeout+0x86c/0xe50 kernel/time/timer.c:1723
 __down_common kernel/locking/semaphore.c:221 [inline]
 __down+0x17f/0x280 kernel/locking/semaphore.c:238
 down+0x57/0x80 kernel/locking/semaphore.c:62
 console_lock+0x24/0x70 kernel/printk/printk.c:2216
 paste_selection+0xd7/0x414 drivers/tty/vt/selection.c:366
 tioclinux+0xfd/0x400 drivers/tty/vt/vt.c:2707
 vt_ioctl+0x14e8/0x1f20 drivers/tty/vt/vt_ioctl.c:372
 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45cba9
RSP: 002b:00007f9924cb1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004f0b60 RCX: 000000000045cba9
RDX: 0000000020000000 RSI: 000000000000541c RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005a9 R14: 00000000004c86fa R15: 00007f9924cb26d4
INFO: task syz-executor.3:8681 blocked for more than 140 seconds.
      Not tainted 4.14.184-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29568  8681   6350 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x8a6/0x1d70 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_timeout+0x86c/0xe50 kernel/time/timer.c:1723
 __down_common kernel/locking/semaphore.c:221 [inline]
 __down+0x17f/0x280 kernel/locking/semaphore.c:238
 down+0x57/0x80 kernel/locking/semaphore.c:62
 console_lock+0x24/0x70 kernel/printk/printk.c:2216
 paste_selection+0xd7/0x414 drivers/tty/vt/selection.c:366
 tioclinux+0xfd/0x400 drivers/tty/vt/vt.c:2707
 vt_ioctl+0x14e8/0x1f20 drivers/tty/vt/vt_ioctl.c:372
 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45cba9
RSP: 002b:00007f9924c90c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004f0b60 RCX: 000000000045cba9
RDX: 0000000020000000 RSI: 000000000000541c RDI: 0000000000000003
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005a9 R14: 00000000004c86fa R15: 00007f9924c916d4

Showing all locks held in the system:
1 lock held by khungtaskd/1036:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8146c8d0>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by in:imklog/5967:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff8191e4e6>] __fdget_pos+0xa6/0xc0 fs/file.c:769

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

NMI backtrace for cpu 1
CPU: 1 PID: 1036 Comm: khungtaskd Not tainted 4.14.184-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+0x1b2/0x283 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5e2/0xb80 kernel/hung_task.c:274
 kthread+0x30d/0x420 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: 8618 Comm: syz-executor.4 Not tainted 4.14.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88808f8fe6c0 task.stack: ffff888052660000
RIP: 0010:mark_lock+0xa6/0x1040 kernel/locking/lockdep.c:3168
RSP: 0018:ffff8880aec07918 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff89f0d950 RCX: 1ffff11011f1fdfc
RDX: 1ffffffff13e1b30 RSI: ffff88808f8fefc0 RDI: ffffffff89f0d980
RBP: ffff88808f8fefc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
R13: ffff88808f8fefe0 R14: ffff88808f8fe6c0 R15: 0000000000000002
FS:  00007f8e96a09700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f29b72df000 CR3: 0000000091379000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 mark_held_locks+0xa6/0xf0 kernel/locking/lockdep.c:2854
 __trace_hardirqs_on_caller kernel/locking/lockdep.c:2875 [inline]
 trace_hardirqs_on_caller+0x288/0x580 kernel/locking/lockdep.c:2930
 slab_alloc mm/slab.c:3383 [inline]
 kmem_cache_alloc+0x2c8/0x3c0 mm/slab.c:3550
 dst_alloc+0xe4/0x170 net/core/dst.c:107
 __ip6_dst_alloc+0x2e/0x50 net/ipv6/route.c:357
 ip6_dst_alloc+0x2a/0x1d0 net/ipv6/route.c:370
 icmp6_dst_alloc+0x155/0x580 net/ipv6/route.c:1768
 ndisc_send_skb+0xcff/0x1390 net/ipv6/ndisc.c:463
 ndisc_send_rs+0x125/0x630 net/ipv6/ndisc.c:677
 addrconf_rs_timer+0x280/0x5a0 net/ipv6/addrconf.c:3765
 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279
 expire_timers+0x233/0x4d0 kernel/time/timer.c:1318
 __run_timers kernel/time/timer.c:1636 [inline]
 run_timer_softirq+0x1d8/0x5b0 kernel/time/timer.c:1649
 __do_softirq+0x254/0x9bf kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x15b/0x1a0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5f0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
 </IRQ>
RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline]
RIP: 0010:vga16fb_fillrect+0x943/0x1880 drivers/video/fbdev/vga16fb.c:923
RSP: 0018:ffff8880526673e0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: ffff8880000a0050 RCX: ffffc9000ad15000
RDX: 0000000000040000 RSI: ffffffff831f9ef3 RDI: ffff888052667490
RBP: 0000000000000050 R08: 000000000000ffff R09: ffffed104324c844
R10: ffffed104324c843 R11: ffff88821926421f R12: ffff8880000a000e
R13: 0000000000000000 R14: 00000000fbee866b R15: 000000000000004f
 bit_clear_margins+0x2a4/0x480 drivers/video/fbdev/core/bitblit.c:232
 fbcon_clear_margins+0x274/0x300 drivers/video/fbdev/core/fbcon.c:1320
 fbcon_switch+0xc4e/0x1700 drivers/video/fbdev/core/fbcon.c:2302
 redraw_screen+0x332/0x760 drivers/tty/vt/vt.c:689
 fbcon_modechanged+0x552/0x800 drivers/video/fbdev/core/fbcon.c:2949
 fbcon_event_notify+0x11a/0x1750 drivers/video/fbdev/core/fbcon.c:3302
 notifier_call_chain+0x107/0x1a0 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+0x79/0x90 kernel/notifier.c:325
 fb_set_var+0xaad/0xc70 drivers/video/fbdev/core/fbmem.c:1054
 do_fb_ioctl+0x3cc/0x840 drivers/video/fbdev/core/fbmem.c:1127
 fb_ioctl+0xda/0x120 drivers/video/fbdev/core/fbmem.c:1242
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45cba9
RSP: 002b:00007f8e96a08c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e6560 RCX: 000000000045cba9
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 000000000000000d
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000311 R14: 00000000004c59ee R15: 00007f8e96a096d4
Code: 50 01 00 00 48 81 eb 50 01 00 00 48 81 c3 c0 d9 e9 89 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 fc 0b 00 00 4c 85 63 30 0f 84 9c 00 00 00 b8 01 00 00 00 

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/07/15 23:24 linux-4.14.y b850307b279c ada108d0 .config log report