* INFO: rcu detected stall in __schedule
@ 2018-05-02 17:56 syzbot
2018-05-03 5:45 ` Tetsuo Handa
0 siblings, 1 reply; 3+ messages in thread
From: syzbot @ 2018-05-02 17:56 UTC (permalink / raw)
To: linux-kernel, linux-ppp, netdev, paulus, syzkaller-bugs
Hello,
syzbot found the following crash on:
HEAD commit: f2125992e7cb Merge tag 'xfs-4.17-fixes-1' of
git://git.kern...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?id=4755940087693312
kernel config:
https://syzkaller.appspot.com/x/.config?id=6493557782959164711
dashboard link: https://syzkaller.appspot.com/bug?extid=f16b3e3512a1e3c1d1f6
compiler: gcc (GCC) 8.0.1 20180413 (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+f16b3e3512a1e3c1d1f6@syzkaller.appspotmail.com
do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app
do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app
ntfs: (device loop6): parse_options(): Unrecognized mount option
error�n��uldip.
INFO: rcu_sched self-detected stall on CPU
0-...!: (125000 ticks this GP) idle=f3e/1/4611686018427387906
softirq=112858/112858 fqs=0
(t=125000 jiffies g=61626 c=61625 q=1534)
rcu_sched kthread starved for 125000 jiffies! g61626 c61625 f0x0
RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
RCU grace-period kthread stack dump:
rcu_sched I23592 9 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2848 [inline]
__schedule+0x801/0x1e30 kernel/sched/core.c:3490
schedule+0xef/0x430 kernel/sched/core.c:3549
schedule_timeout+0x138/0x240 kernel/time/timer.c:1801
rcu_gp_kthread+0x6b5/0x1940 kernel/rcu/tree.c:2231
kthread+0x345/0x410 kernel/kthread.c:238
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
NMI backtrace for cpu 0
CPU: 0 PID: 26694 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1376
print_cpu_stall kernel/rcu/tree.c:1525 [inline]
check_cpu_stall.isra.61.cold.80+0x36c/0x59a kernel/rcu/tree.c:1593
__rcu_pending kernel/rcu/tree.c:3356 [inline]
rcu_pending kernel/rcu/tree.c:3401 [inline]
rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763
update_process_times+0x2d/0x70 kernel/time/timer.c:1636
tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
__run_hrtimer kernel/time/hrtimer.c:1398 [inline]
__hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1460
hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
</IRQ>
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline]
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168
[inline]
RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192
RSP: 0018:ffff8801b3dbf438 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff8801dae2c680 RCX: 1ffff100361ebd4d
RDX: 1ffffffff11a316f RSI: ffff8801b0f5ea48 RDI: ffffffff88d18b78
RBP: ffff8801b3dbf440 R08: ffff8801b0f5e9f8 R09: 0000000000000006
R10: ffff8801b0f5e1c0 R11: 0000000000000000 R12: ffff8801b0f5e1c0
R13: ffff8801b0f5e7a0 R14: dffffc0000000000 R15: ffff8801b0f5e1c0
rq_unlock_irq kernel/sched/sched.h:1824 [inline]
__schedule+0x144f/0x1e30 kernel/sched/core.c:3493
schedule+0xef/0x430 kernel/sched/core.c:3549
do_sched_yield+0x187/0x240 kernel/sched/core.c:4965
yield+0xa5/0xe0 kernel/sched/core.c:5054
tasklet_kill+0x4e/0xd0 kernel/softirq.c:559
ppp_asynctty_close+0x9e/0x150 drivers/net/ppp/ppp_async.c:239
ppp_asynctty_hangup+0x15/0x20 drivers/net/ppp/ppp_async.c:256
tty_ldisc_hangup+0x138/0x640 drivers/tty/tty_ldisc.c:730
__tty_hangup.part.21+0x2da/0x6e0 drivers/tty/tty_io.c:621
__tty_hangup drivers/tty/tty_io.c:571 [inline]
tty_vhangup+0x21/0x30 drivers/tty/tty_io.c:694
pty_close+0x3bd/0x510 drivers/tty/pty.c:78
tty_release+0x494/0x12e0 drivers/tty/tty_io.c:1656
__fput+0x34d/0x890 fs/file_table.c:209
____fput+0x15/0x20 fs/file_table.c:243
task_work_run+0x1e4/0x290 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166
prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455979
RSP: 002b:00007f92c3751c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f92c37526d4 RCX: 0000000000455979
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000013
RBP: 000000000072bf50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000053 R14: 00000000006f4868 R15: 0000000000000001
---
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 syzkaller@googlegroups.com.
syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is
merged
into any tree, please reply to this email with:
#syz fix: exact-commit-title
To mark this as a duplicate of another syzbot report, please reply with:
#syz dup: exact-subject-of-another-report
If it's a one-off invalid bug report, please reply with:
#syz invalid
Note: if the crash happens again, it will cause creation of a new bug
report.
Note: all commands must start from beginning of the line in the email body.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: INFO: rcu detected stall in __schedule
2018-05-02 17:56 INFO: rcu detected stall in __schedule syzbot
@ 2018-05-03 5:45 ` Tetsuo Handa
2018-05-03 6:07 ` Dmitry Vyukov
0 siblings, 1 reply; 3+ messages in thread
From: Tetsuo Handa @ 2018-05-03 5:45 UTC (permalink / raw)
To: syzbot, syzkaller-bugs, dvyukov; +Cc: linux-kernel, linux-ppp, netdev, paulus
I'm not sure whether this is a PPP bug.
As of uptime = 484, RCU says that it stalled for 125 seconds.
----------
[ 484.407032] INFO: rcu_sched self-detected stall on CPU
[ 484.412488] 0-...!: (125000 ticks this GP) idle=f3e/1/4611686018427387906 softirq=112858/112858 fqs=0
[ 484.422300] (t=125000 jiffies g=61626 c=61625 q=1534)
[ 484.427663] rcu_sched kthread starved for 125000 jiffies! g61626 c61625 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
----------
484 - 125 = 359, which was about to start SND related fuzzing in that log.
----------
2033/05/18 03:36:31 executing program 1:
r0 = socket(0x40000a, 0x5, 0x7)
setsockopt$inet_int(r0, 0x0, 0x18, &(0x7f0000000000)=0x200, 0x4)
bind$inet6(r0, &(0x7f00000000c0)={0xa, 0x0, 0x0, @loopback={0x0, 0x1}}, 0x1c)
perf_event_open(&(0x7f0000000040)={0x2, 0x70, 0x3e5}, 0x0, 0xffffffffffffffff, 0xffffffffffffffff, 0x0)
timer_create(0x0, &(0x7f00000001c0)={0x0, 0x15, 0x0, @thr={&(0x7f0000000440), &(0x7f0000000540)}}, &(0x7f0000000200))
timer_getoverrun(0x0)
perf_event_open(&(0x7f000025c000)={0x2, 0x78, 0x3e3}, 0x0, 0x0, 0xffffffffffffffff, 0x0)
r1 = syz_open_dev$sndctrl(&(0x7f0000000200)='/dev/snd/controlC#\x00', 0x2, 0x0)
perf_event_open(&(0x7f0000001000)={0x0, 0x70, 0x0, 0x0, 0x0, 0x0, 0x0, 0x8ce, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffffffffffffff8, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @perf_bp={&(0x7f0000005000), 0x2}, 0x1000000000c}, 0x0, 0x0, 0xffffffffffffffff, 0x0)
ioctl$SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS(r1, 0xc0045516, &(0x7f00000000c0)=0x1)
r2 = syz_open_dev$sndpcmp(&(0x7f0000000100)='/dev/snd/pcmC#D#p\x00', 0x1, 0x4000)
ioctl$SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT(r2, 0xc04c5349, &(0x7f0000000240)={0x200, 0xfffffffffffffcdc, 0x1})
syz_open_dev$tun(&(0x7f00000003c0)='/dev/net/tun\x00', 0x0, 0x20402)
ioctl$SNDRV_CTL_IOCTL_PVERSION(r1, 0xc1105517, &(0x7f0000001000)=""/250)
ioctl$SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS(r1, 0xc0045516, &(0x7f0000000000))
2033/05/18 03:36:31 executing program 4:
syz_emit_ethernet(0x3e, &(0x7f00000000c0)={@broadcast=[0xff, 0xff, 0xff, 0xff, 0xff, 0xff], @empty=[0x0, 0x0, 0xb00000000000000], [], {@ipv4={0x800, {{0x5, 0x4, 0x0, 0x0, 0x30, 0x0, 0x0, 0x0, 0x1, 0x0, @remote={0xac, 0x14, 0x14, 0xbb}, @dev={0xac, 0x14, 0x14}}, @icmp=@parameter_prob={0x5, 0x4, 0x0, 0x0, 0x0, 0x0, {0x5, 0x4, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @local={0xac, 0x223, 0x14, 0xaa}, @dev={0xac, 0x14, 0x14}}}}}}}, &(0x7f0000000000)={0x0, 0x2, [0x0, 0x2e6]})
2033/05/18 03:36:31 executing program 1:
r0 = socket$pppoe(0x18, 0x1, 0x0)
connect$pppoe(r0, &(0x7f00000000c0)={0x18, 0x0, {0x1, @broadcast=[0xff, 0xff, 0xff, 0xff, 0xff, 0xff], 'ip6_vti0\x00'}}, 0x1e)
r1 = socket(0x3, 0xb, 0x80000001)
setsockopt$inet_sctp6_SCTP_ADAPTATION_LAYER(r1, 0x84, 0x7, &(0x7f0000000100)={0x2}, 0x4)
ioctl$sock_inet_SIOCGIFADDR(r0, 0x8915, &(0x7f0000000040)={'veth1_to_bridge\x00', {0x2, 0x4e21}})
r2 = syz_open_dev$admmidi(&(0x7f0000000000)='/dev/admmidi#\x00', 0x6, 0x8000)
setsockopt$SO_VM_SOCKETS_BUFFER_MAX_SIZE(r2, 0x28, 0x2, &(0x7f0000000080)=0xffffffffffffff00, 0x8)
[ 359.306427] snd_virmidi snd_virmidi.0: control 112:0:0:�\b:0 is already present
----------
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: INFO: rcu detected stall in __schedule
2018-05-03 5:45 ` Tetsuo Handa
@ 2018-05-03 6:07 ` Dmitry Vyukov
0 siblings, 0 replies; 3+ messages in thread
From: Dmitry Vyukov @ 2018-05-03 6:07 UTC (permalink / raw)
To: Tetsuo Handa; +Cc: syzbot, syzkaller-bugs, LKML, linux-ppp, netdev, paulus
On Thu, May 3, 2018 at 7:45 AM, Tetsuo Handa
<penguin-kernel@i-love.sakura.ne.jp> wrote:
> I'm not sure whether this is a PPP bug.
>
> As of uptime = 484, RCU says that it stalled for 125 seconds.
>
> ----------
> [ 484.407032] INFO: rcu_sched self-detected stall on CPU
> [ 484.412488] 0-...!: (125000 ticks this GP) idle=f3e/1/4611686018427387906 softirq=112858/112858 fqs=0
> [ 484.422300] (t=125000 jiffies g=61626 c=61625 q=1534)
> [ 484.427663] rcu_sched kthread starved for 125000 jiffies! g61626 c61625 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
> ----------
>
> 484 - 125 = 359, which was about to start SND related fuzzing in that log.
>
> ----------
> 2033/05/18 03:36:31 executing program 1:
> r0 = socket(0x40000a, 0x5, 0x7)
> setsockopt$inet_int(r0, 0x0, 0x18, &(0x7f0000000000)=0x200, 0x4)
> bind$inet6(r0, &(0x7f00000000c0)={0xa, 0x0, 0x0, @loopback={0x0, 0x1}}, 0x1c)
> perf_event_open(&(0x7f0000000040)={0x2, 0x70, 0x3e5}, 0x0, 0xffffffffffffffff, 0xffffffffffffffff, 0x0)
> timer_create(0x0, &(0x7f00000001c0)={0x0, 0x15, 0x0, @thr={&(0x7f0000000440), &(0x7f0000000540)}}, &(0x7f0000000200))
> timer_getoverrun(0x0)
> perf_event_open(&(0x7f000025c000)={0x2, 0x78, 0x3e3}, 0x0, 0x0, 0xffffffffffffffff, 0x0)
> r1 = syz_open_dev$sndctrl(&(0x7f0000000200)='/dev/snd/controlC#\x00', 0x2, 0x0)
> perf_event_open(&(0x7f0000001000)={0x0, 0x70, 0x0, 0x0, 0x0, 0x0, 0x0, 0x8ce, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xfffffffffffffff8, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @perf_bp={&(0x7f0000005000), 0x2}, 0x1000000000c}, 0x0, 0x0, 0xffffffffffffffff, 0x0)
> ioctl$SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS(r1, 0xc0045516, &(0x7f00000000c0)=0x1)
> r2 = syz_open_dev$sndpcmp(&(0x7f0000000100)='/dev/snd/pcmC#D#p\x00', 0x1, 0x4000)
> ioctl$SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT(r2, 0xc04c5349, &(0x7f0000000240)={0x200, 0xfffffffffffffcdc, 0x1})
> syz_open_dev$tun(&(0x7f00000003c0)='/dev/net/tun\x00', 0x0, 0x20402)
> ioctl$SNDRV_CTL_IOCTL_PVERSION(r1, 0xc1105517, &(0x7f0000001000)=""/250)
> ioctl$SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS(r1, 0xc0045516, &(0x7f0000000000))
>
> 2033/05/18 03:36:31 executing program 4:
> syz_emit_ethernet(0x3e, &(0x7f00000000c0)={@broadcast=[0xff, 0xff, 0xff, 0xff, 0xff, 0xff], @empty=[0x0, 0x0, 0xb00000000000000], [], {@ipv4={0x800, {{0x5, 0x4, 0x0, 0x0, 0x30, 0x0, 0x0, 0x0, 0x1, 0x0, @remote={0xac, 0x14, 0x14, 0xbb}, @dev={0xac, 0x14, 0x14}}, @icmp=@parameter_prob={0x5, 0x4, 0x0, 0x0, 0x0, 0x0, {0x5, 0x4, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @local={0xac, 0x223, 0x14, 0xaa}, @dev={0xac, 0x14, 0x14}}}}}}}, &(0x7f0000000000)={0x0, 0x2, [0x0, 0x2e6]})
>
> 2033/05/18 03:36:31 executing program 1:
> r0 = socket$pppoe(0x18, 0x1, 0x0)
> connect$pppoe(r0, &(0x7f00000000c0)={0x18, 0x0, {0x1, @broadcast=[0xff, 0xff, 0xff, 0xff, 0xff, 0xff], 'ip6_vti0\x00'}}, 0x1e)
> r1 = socket(0x3, 0xb, 0x80000001)
> setsockopt$inet_sctp6_SCTP_ADAPTATION_LAYER(r1, 0x84, 0x7, &(0x7f0000000100)={0x2}, 0x4)
> ioctl$sock_inet_SIOCGIFADDR(r0, 0x8915, &(0x7f0000000040)={'veth1_to_bridge\x00', {0x2, 0x4e21}})
> r2 = syz_open_dev$admmidi(&(0x7f0000000000)='/dev/admmidi#\x00', 0x6, 0x8000)
> setsockopt$SO_VM_SOCKETS_BUFFER_MAX_SIZE(r2, 0x28, 0x2, &(0x7f0000000080)=0xffffffffffffff00, 0x8)
>
> [ 359.306427] snd_virmidi snd_virmidi.0: control 112:0:0:� :0 is already present
> ----------
It's the next one that caused the hang (the number in "Comm:
syz-executor1" matches with the number in "executing program 1"):
[ 359.306427] snd_virmidi snd_virmidi.0: control 112:0:0:� :0 is
already present
2033/05/18 03:36:31 executing program 1:
r0 = openat$ptmx(0xffffffffffffff9c,
&(0x7f0000000140)='/dev/ptmx\x00', 0x0, 0x0)
ioctl$TCSETS(r0, 0x40045431, &(0x7f00005befdc))
r1 = syz_open_pts(r0, 0x20201)
fcntl$setstatus(r1, 0x4, 0x2800)
ioctl$TCXONC(r1, 0x540a, 0x0)
perf_event_open(&(0x7f000025c000)={0x2, 0x70, 0x3e5, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @perf_bp={&(0x7f000031f000)}}, 0x0,
0x0, 0xffffffffffffffff, 0x0)
write(r1, &(0x7f0000fd6000)='z', 0x1)
r2 = openat$ipvs(0xffffffffffffff9c,
&(0x7f0000000000)='/proc/sys/net/ipv4/vs/sync_ports\x00', 0x2, 0x0)
ioctl$ifreq_SIOCGIFINDEX_team(0xffffffffffffff9c, 0x8933,
&(0x7f00000012c0)={'team0\x00', <r3=>0x0})
bind$packet(r2, &(0x7f0000001300)={0x11, 0x1f, r3, 0x1, 0x0, 0x6,
@random="31e8917e98e6"}, 0x14)
ioctl$TIOCSETD(r1, 0x5423, &(0x7f00000000c0)=0x3)
ioctl$TCFLSH(r0, 0x540b, 0x0)
close(r0)
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2018-05-03 6:07 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-05-02 17:56 INFO: rcu detected stall in __schedule syzbot
2018-05-03 5:45 ` Tetsuo Handa
2018-05-03 6:07 ` Dmitry Vyukov
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).