INFO: task hung in do_splice

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b2e45b46d85b Merge tag 'iommu-fixes-v4.19-rc6' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=134157c6400000
kernel config: https://syzkaller.appspot.com/x/.config?x=c0af03fe452b65fb
dashboard link: https://syzkaller.appspot.com/bug?extid=53904d031b5951a29c81
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [linux-...@vger.kernel.org linux-...@vger.kernel.org
vi...@zeniv.linux.org.uk]

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+53904d...@syzkaller.appspotmail.com

loop3: partition table partially beyond EOD, truncated
loop3: p1 size 2 extends beyond EOD, truncated
loop3: p4 start 1854537728 is beyond EOD, truncated
INFO: task syz-executor4:10390 blocked for more than 140 seconds.
Not tainted 4.19.0-rc6+ #48
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4 D25632 10390 11205 0x00000000
Call Trace:
context_switch kernel/sched/core.c:2825 [inline]
__schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
schedule+0xfe/0x460 kernel/sched/core.c:3517
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3575
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0xbe7/0x1700 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
pipe_lock_nested fs/pipe.c:62 [inline]
pipe_lock+0x6e/0x80 fs/pipe.c:70
do_splice+0xe79/0x1430 fs/splice.c:1171
__do_sys_splice fs/splice.c:1415 [inline]
__se_sys_splice fs/splice.c:1395 [inline]
__x64_sys_splice+0x2c1/0x330 fs/splice.c:1395
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f6b3cbd7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 000000000072bf00 R08: 000000000000ced1 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b3cbd86d4
R13: 00000000004c4f63 R14: 00000000004d7a40 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 981 Comm: khungtaskd Not tainted 4.19.0-rc6+ #48
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+0x1c4/0x2b4 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
watchdog+0xb3e/0x1050 kernel/hung_task.c:265
kthread+0x35a/0x420 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc6+ #48
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:weighted_cpuload kernel/sched/fair.c:5266 [inline]
RIP: 0010:cpu_load_update_nohz_start+0x54/0xb0 kernel/sched/fair.c:5332
Code: 89 48 89 f9 48 c1 e9 03 80 3c 11 00 75 55 48 03 1c c5 e0 9e 00 89 48
b8 00 00 00 00 00 fc ff df 48 8d bb 68 01 00 00 48 89 fa <48> c1 ea 03 80
3c 02 00 75 45 48 8d 7b 48 4c 8b a3 68 01 00 00 48
RSP: 0018:ffff8801d9b2fc10 EFLAGS: 00000082
RAX: dffffc0000000000 RBX: ffff8801daf2cb40 RCX: 1ffffffff12013dd
RDX: ffff8801daf2cca8 RSI: ffffffff838d27a8 RDI: ffff8801daf2cca8
RBP: ffff8801d9b2fc28 R08: ffff8801d9b1e3c0 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1003b365f8f
R13: ffff8801daf264ac R14: 000001133dc23724 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000790d60 CR3: 0000000190790000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
tick_nohz_stop_tick kernel/time/tick-sched.c:778 [inline]
__tick_nohz_idle_stop_tick kernel/time/tick-sched.c:939 [inline]
tick_nohz_idle_stop_tick+0x393/0xe10 kernel/time/tick-sched.c:960
cpuidle_idle_call kernel/sched/idle.c:150 [inline]
do_idle+0x3d1/0x5b0 kernel/sched/idle.c:262
cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368
start_secondary+0x447/0x5f0 arch/x86/kernel/smpboot.c:271
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243


---
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#bug-status-tracking for how to communicate with
syzbot.

[syzbot]

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