# 威联通NAS夜半死机：未操作时停止响应，只能强行关机

## 症状

最近碰到了比较折腾人的问题，每天夜间一点到四点，NAS会在某一时间停止响应，并且不会自动恢复，直到强行关机重启才能恢复。

根据阿里云自动监控nas上个人网站的记录，大约是在一点到四点之间停止响应，但阿里云有时候延迟很多，实际停止响应的时间应该比这早。

昨天我打开网页控制台并持续录屏，发现失去响应前后，Qboost和资源监控器的显示没有明显变化（或者是死机太快来不及反映在网页界面上），就是突然多出一个CPU占用%30的系统内核进程，然后网页就断开了。

失去响应期间，ssh无法登录，用ssh -vvv尝试登录发现卡在“we sent a key， wait for response”步骤。但是看硬盘灯的话，`QVR Pro`似乎还能工作。

第一次失去响应的时候，因为以前遇到过确实是有比较重的任务，就等了一天，结果还是不能用。第二天等了半天也是不行。于是第三天第四天就直接强关了，记得重新开机后检查文件系统。

## 一些尝试

首先被怀疑的是自动缩略图生成服务，这东西耗CPU我是知道的。这两天刚好下载了几个蓝光，会不会是缩略图生成累死了机器？尝试了禁止为视频文件生成缩略图，甚至关掉这个功能，但第二天起来还是死机。

然后怀疑`hybrid backup`的计划备份，因为第一天出问题是四点，而我依稀记得设置了三点左右自动备份，而且第二天强关后的错误记录里面有一条“因为异常断电，备份没有完成”。于是把这个时间调整到一点，于是下次死机的时间变成了两点多（看阿里云报错），我以为找对了，是以前创建的备份任务与新版不兼容。但重新设置了备份后，第三天还是死机。并且我手动启动了一次备份，并没有死机。

查相关故障，很难搜，只是有一个去年的“360发现威联通平台挖矿病毒”的消息，查了一下不像。毕竟如果一个作者注意到要在白天挺直挖矿，却在晚上全速运行到死机，是有点精神分裂的。

找了一圈找设置在晚上的定时任务，没找到时间完全对得上的。

后面就没辙了，第三天我让电脑打开网页界面，整晚上开着，然后开了个录屏，要看看到底是何方神圣，结果啥也没看到。就是有一瞬间屏幕中出现了一个占30% CPU的“内核进程”，然后网页界面停止刷新，一分钟后报错显示断开，没了。

 {{:hardware:nas:录屏截图-正常运行.png?200|}} {{:hardware:nas:录屏截图-出现了占用较高的内核进程_随后网页停止刷新.png?200|}} {{:hardware:nas:录屏截图-网页界面停止响应并最终提示断开.png?200|}}

## 日志分析

于是我觉得这事儿不能忍了，打算报威联通技术支持，报支持过程中发现需要详细日志，可以用“支持平台”APP生成，这个我之前就卸载了，现在只好装回来，然后生成一份日志（zip包），填信息报支持，然后自己分析。

通过时间对应，发现确实有四次彻底死机，分布在凌晨一点到四点之间，特征是在这之前一直陆续有`kernel message`刷新，但某一瞬间过后完全没有日志，下一条就是第二天上午或下午的开机信息。这说明情况起码严重到了日志都写不下去的地步。

于是分析司机前一瞬间的共同特征，倒是挺明显的，类似以下的一端日志在每次死机之前都出现了，在其他时候一次都没出现：

```
2022-01-11 03:00:59 +08:00 <4> [58878.505271] EXT4-fs (dm-114): Mount option "noacl" will be removed by 3.5
2022-01-11 03:00:59 +08:00 <4> [58878.505271] Contact linux-ext4@vger.kernel.org if you think we should keep it.
2022-01-11 03:00:59 +08:00 <4> [58878.505271] 
2022-01-11 03:00:59 +08:00 <6> [58878.676229] ext4_init_reserve_inode_table0: dm-114, 24576
2022-01-11 03:00:59 +08:00 <6> [58878.681715] ext4_init_reserve_inode_table2: dm-114, 24576, 0, 0, 4096
2022-01-11 03:00:59 +08:00 <6> [58878.725057] EXT4-fs (dm-114): orphan cleanup on readonly fs
2022-01-11 03:01:00 +08:00 <6> [58879.015642] EXT4-fs (dm-114): 16 orphan inodes deleted
2022-01-11 03:01:00 +08:00 <6> [58879.183505] EXT4-fs (dm-114): recovery complete
2022-01-11 03:01:00 +08:00 <6> [58879.320703] EXT4-fs (dm-114): mounted filesystem with ordered data mode. Opts: usrjquota=aquota.user,jqfmt=vfsv1,user_xattr,data=ordered,data_err=abort,delalloc,nopriv,nodiscard,noacl
2022-01-11 03:01:03 +08:00 <6> [58882.542275] ext4_init_reserve_inode_table0: dm-114, 24576
2022-01-11 03:01:03 +08:00 <6> [58882.547749] ext4_init_reserve_inode_table2: dm-114, 24576, 0, 0, 4096
2022-01-11 03:01:03 +08:00 <6> [58882.617280] EXT4-fs (dm-114): mounted filesystem with ordered data mode. Opts: usrjquota=aquota.user,jqfmt=vfsv1,user_xattr,data=ordered,data_err=abort,delalloc,nopriv,nodiscard,acl
2022-01-11 03:01:13 +08:00 <4> [58892.638787] ext2 filesystem being mounted at /tmp/nasconfig_tmp supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:20 +08:00 <4> [58898.975028] ext2 filesystem being mounted at /tmp/nasconfig_tmp supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:30 +08:00 <4> [58908.944119] ext2 filesystem being mounted at /tmp/nasconfig_tmp supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:33 +08:00 <4> [58912.249198] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:33 +08:00 <4> [58912.299864] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:34 +08:00 <4> [58912.948026] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:37 +08:00 <4> [58916.328700] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:01:37 +08:00 <4> [58916.363656] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:02:23 +08:00 <4> [58962.421353] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:02:43 +08:00 <4> [58981.940206] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:02:43 +08:00 <4> [58982.059447] ext2 filesystem being mounted at /tmp/config supports timestamps until 2038 (0x7fffffff)
2022-01-11 03:14:11 +08:00 <4> [59670.847551] EXT4-fs (dm-53): Mount option "noacl" will be removed by 3.5
2022-01-11 03:14:11 +08:00 <4> [59670.847551] Contact linux-ext4@vger.kernel.org if you think we should keep it.
2022-01-11 03:14:11 +08:00 <4> [59670.847551] 
2022-01-11 03:14:12 +08:00 <6> [59671.021426] ext4_init_reserve_inode_table0: dm-53, 24576
2022-01-11 03:14:12 +08:00 <6> [59671.026806] ext4_init_reserve_inode_table2: dm-53, 24576, 0, 0, 4096
2022-01-11 03:14:12 +08:00 <6> [59671.036967] EXT4-fs (dm-53): orphan cleanup on readonly fs
2022-01-11 03:14:12 +08:00 <6> [59671.346769] EXT4-fs (dm-53): 16 orphan inodes deleted
2022-01-11 03:14:12 +08:00 <6> [59671.642693] EXT4-fs (dm-53): recovery complete
2022-01-11 03:14:12 +08:00 <6> [59671.820782] EXT4-fs (dm-53): mounted filesystem with ordered data mode. Opts: usrjquota=aquota.user,jqfmt=vfsv1,user_xattr,data=ordered,data_err=abort,delalloc,nopriv,nodiscard,noacl
2022-01-11 03:17:06 +08:00 <3> [59845.231117] INFO: task python:2884 blocked for more than 122 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.237600]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.243367] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.251231] task:python          state:D stack:    0 pid: 2884 ppid:     1 flags:0x00000000
2022-01-11 03:17:06 +08:00 <6> [59845.259602] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.262079]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.265596]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.268764]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:06 +08:00 <6> [59845.272797]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.276743]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:06 +08:00 <6> [59845.280777]  vfs_write+0x2ad/0x2e0
2022-01-11 03:17:06 +08:00 <6> [59845.284199]  ksys_write+0x50/0xc0
2022-01-11 03:17:06 +08:00 <6> [59845.287530]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:06 +08:00 <6> [59845.291127]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:06 +08:00 <6> [59845.296200] RIP: 0033:0x7f49325415d0
2022-01-11 03:17:06 +08:00 <6> [59845.299793] RSP: 002b:00007ffdaf30bb78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
2022-01-11 03:17:06 +08:00 <6> [59845.307380] RAX: ffffffffffffffda RBX: 00000000000000a1 RCX: 00007f49325415d0
2022-01-11 03:17:06 +08:00 <6> [59845.314536] RDX: 00000000000000a1 RSI: 00007f493334c000 RDI: 0000000000000005
2022-01-11 03:17:06 +08:00 <6> [59845.321689] RBP: 00007f493334c000 R08: 0000000001a4bc60 R09: 00007f4933343700
2022-01-11 03:17:06 +08:00 <6> [59845.328843] R10: 00007f4933343700 R11: 0000000000000246 R12: 0000000001a4bb80
2022-01-11 03:17:06 +08:00 <6> [59845.336002] R13: 00000000000000a1 R14: 00007f492d11e820 R15: 00007f492d127b90
2022-01-11 03:17:06 +08:00 <3> [59845.343338] INFO: task dockerd:5018 blocked for more than 122 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.349891]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.355666] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.363520] task:dockerd         state:D stack:    0 pid: 5018 ppid:  2884 flags:0x00004000
2022-01-11 03:17:06 +08:00 <6> [59845.371895] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.374362]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.377876]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.381083]  io_schedule+0xd/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.384423]  filemap_fault+0x3cd/0xa70
2022-01-11 03:17:06 +08:00 <6> [59845.388201]  ? generic_perform_write+0x1e0/0x1e0
2022-01-11 03:17:06 +08:00 <6> [59845.392839]  ext4_filemap_fault+0x27/0x40
2022-01-11 03:17:06 +08:00 <6> [59845.396882]  __do_fault+0x2f/0xf0
2022-01-11 03:17:06 +08:00 <6> [59845.400225]  handle_mm_fault+0xa7b/0xf00
2022-01-11 03:17:06 +08:00 <6> [59845.404168]  exc_page_fault+0x23d/0x420
2022-01-11 03:17:06 +08:00 <6> [59845.408028]  ? asm_exc_page_fault+0x8/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.412150]  asm_exc_page_fault+0x1e/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.416179] RIP: 0033:0x4550ae
2022-01-11 03:17:06 +08:00 <6> [59845.419255] RSP: 002b:00007ffe6f2415c8 EFLAGS: 00010293
2022-01-11 03:17:06 +08:00 <6> [59845.424503] RAX: 000000007fffffff RBX: 0000000000000000 RCX: 000000c000f0be00
2022-01-11 03:17:06 +08:00 <6> [59845.431686] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.438849] RBP: 00007ffe6f241890 R08: 0000000000000000 R09: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.446000] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000033bc4f0
2022-01-11 03:17:06 +08:00 <6> [59845.453158] R13: 0000000004557a20 R14: 000000c000f0be00 R15: 00000000033bc4f0
2022-01-11 03:17:06 +08:00 <3> [59845.460641] INFO: task dockerd:5047 blocked for more than 123 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.467208]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.472973] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.480821] task:dockerd         state:D stack:    0 pid: 5047 ppid:  2884 flags:0x00000000
2022-01-11 03:17:06 +08:00 <6> [59845.489189] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.491660]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.495170]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.498332]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:06 +08:00 <6> [59845.502356]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.506297]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:06 +08:00 <6> [59845.510330]  mnt_want_write+0x60/0x80
2022-01-11 03:17:06 +08:00 <6> [59845.514012]  filename_create+0x5f/0x160
2022-01-11 03:17:06 +08:00 <6> [59845.517869]  do_mknodat+0xd4/0x200
2022-01-11 03:17:06 +08:00 <6> [59845.521291]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:06 +08:00 <6> [59845.524890]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:06 +08:00 <6> [59845.529966] RIP: 0033:0x4bf25a
2022-01-11 03:17:06 +08:00 <6> [59845.533039] RSP: 002b:000000c0008e1170 EFLAGS: 00000202 ORIG_RAX: 0000000000000103
2022-01-11 03:17:06 +08:00 <6> [59845.540627] RAX: ffffffffffffffda RBX: 000000c000060000 RCX: 00000000004bf25a
2022-01-11 03:17:06 +08:00 <6> [59845.547776] RDX: 00000000000011c0 RSI: 000000c000157a20 RDI: ffffffffffffff9c
2022-01-11 03:17:06 +08:00 <6> [59845.554924] RBP: 000000c0008e11e0 R08: 0000000000000000 R09: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.562076] R10: 0000000000000000 R11: 0000000000000202 R12: ffffffffffffffff
2022-01-11 03:17:06 +08:00 <6> [59845.569252] R13: 0000000000000027 R14: 0000000000000026 R15: 000000000000002e
2022-01-11 03:17:06 +08:00 <3> [59845.576633] INFO: task dockerd:5116 blocked for more than 123 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.583189]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.588948] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.596795] task:dockerd         state:D stack:    0 pid: 5116 ppid:  2884 flags:0x00000000
2022-01-11 03:17:06 +08:00 <6> [59845.605170] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.607641]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.611156]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.614321]  io_schedule+0xd/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.617652]  filemap_fault+0x3cd/0xa70
2022-01-11 03:17:06 +08:00 <6> [59845.621430]  ? generic_perform_write+0x1e0/0x1e0
2022-01-11 03:17:06 +08:00 <6> [59845.626068]  ext4_filemap_fault+0x27/0x40
2022-01-11 03:17:06 +08:00 <6> [59845.630093]  __do_fault+0x2f/0xf0
2022-01-11 03:17:06 +08:00 <6> [59845.633422]  handle_mm_fault+0xa7b/0xf00
2022-01-11 03:17:06 +08:00 <6> [59845.637361]  exc_page_fault+0x23d/0x420
2022-01-11 03:17:06 +08:00 <6> [59845.641215]  ? asm_exc_page_fault+0x8/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.645332]  asm_exc_page_fault+0x1e/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.649361] RIP: 0033:0x4550ae
2022-01-11 03:17:06 +08:00 <6> [59845.652436] RSP: 002b:00007f844d6be720 EFLAGS: 00010293
2022-01-11 03:17:06 +08:00 <6> [59845.657688] RAX: 000000007fffffff RBX: 0000000000000000 RCX: 000000c000f3ed80
2022-01-11 03:17:06 +08:00 <6> [59845.664848] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.672001] RBP: 00007f844d6be9e8 R08: 0000000000000000 R09: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.679150] R10: 0000000000000000 R11: 0000000000000000 R12: 000000000334eff0
2022-01-11 03:17:06 +08:00 <6> [59845.686302] R13: 0000000004557a20 R14: 00000000024ed724 R15: 0000000000000000
2022-01-11 03:17:06 +08:00 <3> [59845.693677] INFO: task VM Periodic Tas:8389 blocked for more than 123 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.700919]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.706682] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.714523] task:VM Periodic Tas state:D stack:    0 pid: 8389 ppid:  8314 flags:0x00000320
2022-01-11 03:17:06 +08:00 <6> [59845.722892] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.725365]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.728874]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.732037]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:06 +08:00 <6> [59845.736066]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.740004]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:06 +08:00 <6> [59845.744040]  ext4_page_mkwrite+0x3bb/0x540
2022-01-11 03:17:06 +08:00 <6> [59845.748158]  do_page_mkwrite+0x4f/0xb0
2022-01-11 03:17:06 +08:00 <6> [59845.751927]  do_wp_page+0x20e/0x360
2022-01-11 03:17:06 +08:00 <6> [59845.755431]  handle_mm_fault+0x300/0xf00
2022-01-11 03:17:06 +08:00 <6> [59845.759379]  ? tick_sched_handle+0x20/0x50
2022-01-11 03:17:06 +08:00 <6> [59845.763494]  exc_page_fault+0x23d/0x420
2022-01-11 03:17:06 +08:00 <6> [59845.767359]  ? asm_exc_page_fault+0x8/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.771473]  asm_exc_page_fault+0x1e/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.775497] RIP: 0033:0x7fbba7c237be
2022-01-11 03:17:06 +08:00 <6> [59845.779090] RSP: 002b:00007fbb77cfbd60 EFLAGS: 00010206
2022-01-11 03:17:06 +08:00 <6> [59845.784328] RAX: 000000001c2f81d8 RBX: 00007fbba8ffa420 RCX: 0000000000000002
2022-01-11 03:17:06 +08:00 <6> [59845.791474] RDX: 00007fbba7501080 RSI: 00007fbba828492c RDI: 00007fbba0019a60
2022-01-11 03:17:06 +08:00 <6> [59845.798620] RBP: 00007fbb77cfbd70 R08: 00000881df9ac29c R09: 0000000000000032
2022-01-11 03:17:06 +08:00 <6> [59845.805767] R10: 0000000006d3e5c2 R11: 0018e920e8f95290 R12: 0000000000000008
2022-01-11 03:17:06 +08:00 <6> [59845.812918] R13: 00007fbba0150d60 R14: 0000000000000002 R15: 0000000000000001
2022-01-11 03:17:06 +08:00 <3> [59845.820315] INFO: task cc3-fastcgi:19981 blocked for more than 123 seconds.
2022-01-11 03:17:06 +08:00 <3> [59845.827311]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:06 +08:00 <3> [59845.833074] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:06 +08:00 <6> [59845.840922] task:cc3-fastcgi     state:D stack:    0 pid:19981 ppid:     1 flags:0x00000000
2022-01-11 03:17:06 +08:00 <6> [59845.849287] Call Trace:
2022-01-11 03:17:06 +08:00 <6> [59845.851754]  __schedule+0x1dd/0x610
2022-01-11 03:17:06 +08:00 <6> [59845.855260]  schedule+0x41/0xa0
2022-01-11 03:17:06 +08:00 <6> [59845.858430]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:06 +08:00 <6> [59845.862459]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:06 +08:00 <6> [59845.866394]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:06 +08:00 <6> [59845.870426]  vfs_write+0x2ad/0x2e0
2022-01-11 03:17:06 +08:00 <6> [59845.873845]  ksys_write+0x50/0xc0
2022-01-11 03:17:06 +08:00 <6> [59845.877180]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:06 +08:00 <6> [59845.880779]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:06 +08:00 <6> [59845.885854] RIP: 0033:0x7fd1c17ac84d
2022-01-11 03:17:06 +08:00 <6> [59845.889441] RSP: 002b:00007fd1827f9000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
2022-01-11 03:17:06 +08:00 <6> [59845.897024] RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007fd1c17ac84d
2022-01-11 03:17:06 +08:00 <6> [59845.904172] RDX: 0000000000001000 RSI: 000000000184e5c0 RDI: 0000000000000009
2022-01-11 03:17:06 +08:00 <6> [59845.911316] RBP: 00000000017e36c8 R08: 0000000000000016 R09: 00007fd1827f9090
2022-01-11 03:17:06 +08:00 <6> [59845.918471] R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000000
2022-01-11 03:17:06 +08:00 <6> [59845.925626] R13: 000000000184e5c0 R14: 0000000000001000 R15: 0000000000001000
2022-01-11 03:17:07 +08:00 <3> [59845.933248] INFO: task cc3_watchdog.sh:13462 blocked for more than 123 seconds.
2022-01-11 03:17:07 +08:00 <3> [59845.940591]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:07 +08:00 <3> [59845.946356] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:07 +08:00 <6> [59845.954202] task:cc3_watchdog.sh state:D stack:    0 pid:13462 ppid:     1 flags:0x00000000
2022-01-11 03:17:07 +08:00 <6> [59845.962572] Call Trace:
2022-01-11 03:17:07 +08:00 <6> [59845.965036]  __schedule+0x1dd/0x610
2022-01-11 03:17:07 +08:00 <6> [59845.968544]  schedule+0x41/0xa0
2022-01-11 03:17:07 +08:00 <6> [59845.971704]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:07 +08:00 <6> [59845.975734]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:07 +08:00 <6> [59845.979679]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:07 +08:00 <6> [59845.983704]  mnt_want_write+0x60/0x80
2022-01-11 03:17:07 +08:00 <6> [59845.987386]  filename_create+0x5f/0x160
2022-01-11 03:17:07 +08:00 <6> [59845.991238]  do_mkdirat+0x49/0x170
2022-01-11 03:17:07 +08:00 <6> [59845.994652]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:07 +08:00 <6> [59845.998248]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:07 +08:00 <6> [59846.003311] RIP: 0033:0x7f80307d52f7
2022-01-11 03:17:07 +08:00 <6> [59846.006898] RSP: 002b:00007fff1c4458c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000053
2022-01-11 03:17:07 +08:00 <6> [59846.014480] RAX: ffffffffffffffda RBX: 0000000001135008 RCX: 00007f80307d52f7
2022-01-11 03:17:07 +08:00 <6> [59846.021636] RDX: 00007fff1c4458f6 RSI: 00000000000001fd RDI: 00007fff1c4458e0
2022-01-11 03:17:07 +08:00 <6> [59846.028791] RBP: 00007fff1c445a00 R08: 00000000004adf48 R09: 0000000000000004
2022-01-11 03:17:07 +08:00 <6> [59846.035941] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000418e40
2022-01-11 03:17:07 +08:00 <6> [59846.043091] R13: 00007fff1c446830 R14: 0000000000000000 R15: 0000000000000000
2022-01-11 03:17:07 +08:00 <3> [59846.050452] INFO: task manager_svc:12583 blocked for more than 123 seconds.
2022-01-11 03:17:07 +08:00 <3> [59846.057444]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:07 +08:00 <3> [59846.063225] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:07 +08:00 <6> [59846.071064] task:manager_svc     state:D stack:    0 pid:12583 ppid: 11331 flags:0x00000000
2022-01-11 03:17:07 +08:00 <6> [59846.079433] Call Trace:
2022-01-11 03:17:07 +08:00 <6> [59846.081935]  __schedule+0x1dd/0x610
2022-01-11 03:17:07 +08:00 <6> [59846.085439]  schedule+0x41/0xa0
2022-01-11 03:17:07 +08:00 <6> [59846.088600]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:07 +08:00 <6> [59846.092625]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:07 +08:00 <6> [59846.096565]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:07 +08:00 <6> [59846.100586]  mnt_want_write+0x60/0x80
2022-01-11 03:17:07 +08:00 <6> [59846.104269]  path_openat+0x42e/0xeb0
2022-01-11 03:17:07 +08:00 <6> [59846.107860]  ? path_lookupat+0x77/0x120
2022-01-11 03:17:07 +08:00 <6> [59846.111710]  ? filename_lookup+0x108/0x1a0
2022-01-11 03:17:07 +08:00 <6> [59846.115820]  ? rcu_sched_clock_irq+0x2b0/0x770
2022-01-11 03:17:07 +08:00 <6> [59846.120286]  do_filp_open+0x94/0x110
2022-01-11 03:17:07 +08:00 <6> [59846.123882]  ? _copy_to_user+0x1c/0x30
2022-01-11 03:17:07 +08:00 <6> [59846.127645]  ? cp_new_stat+0x154/0x190
2022-01-11 03:17:07 +08:00 <6> [59846.131411]  ? _cond_resched+0x10/0x20
2022-01-11 03:17:07 +08:00 <6> [59846.135173]  ? do_sys_openat2+0x1f3/0x390
2022-01-11 03:17:07 +08:00 <6> [59846.139203]  do_sys_openat2+0x1f3/0x390
2022-01-11 03:17:07 +08:00 <6> [59846.143057]  do_sys_open+0x55/0x70
2022-01-11 03:17:07 +08:00 <6> [59846.146479]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:07 +08:00 <6> [59846.150083]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:07 +08:00 <6> [59846.155166] RIP: 0033:0x7f681e660d19
2022-01-11 03:17:07 +08:00 <6> [59846.158756] RSP: 002b:00007f681618d600 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
2022-01-11 03:17:07 +08:00 <6> [59846.166340] RAX: ffffffffffffffda RBX: 00007f67ec01b7e0 RCX: 00007f681e660d19
2022-01-11 03:17:07 +08:00 <6> [59846.173492] RDX: 0000000000000442 RSI: 000055abeb6160a0 RDI: 00000000ffffff9c
2022-01-11 03:17:07 +08:00 <6> [59846.180653] RBP: 000055abeb4122a3 R08: 0000000000000000 R09: 000055abeb4122a4
2022-01-11 03:17:07 +08:00 <6> [59846.187803] R10: 00000000000001b6 R11: 0000000000000293 R12: 0000000000001000
2022-01-11 03:17:07 +08:00 <6> [59846.194956] R13: 000055abeb4122a2 R14: 0000000000000000 R15: 0000000000000194
2022-01-11 03:17:07 +08:00 <3> [59846.202347] INFO: task WTJourn.Flusher:14439 blocked for more than 123 seconds.
2022-01-11 03:17:07 +08:00 <3> [59846.209695]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:07 +08:00 <3> [59846.215460] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:07 +08:00 <6> [59846.223303] task:WTJourn.Flusher state:D stack:    0 pid:14439 ppid: 11331 flags:0x00000000
2022-01-11 03:17:07 +08:00 <6> [59846.231674] Call Trace:
2022-01-11 03:17:07 +08:00 <6> [59846.234147]  __schedule+0x1dd/0x610
2022-01-11 03:17:07 +08:00 <6> [59846.237654]  schedule+0x41/0xa0
2022-01-11 03:17:07 +08:00 <6> [59846.240844]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:07 +08:00 <6> [59846.244874]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:07 +08:00 <6> [59846.248811]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:07 +08:00 <6> [59846.252839]  vfs_write+0x2ad/0x2e0
2022-01-11 03:17:07 +08:00 <6> [59846.256255]  ksys_pwrite64+0x61/0x90
2022-01-11 03:17:07 +08:00 <6> [59846.259850]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:07 +08:00 <6> [59846.263442]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:07 +08:00 <6> [59846.268511] RIP: 0033:0x7f1b2aa8b04f
2022-01-11 03:17:07 +08:00 <6> [59846.272096] RSP: 002b:00007f1b1f75e410 EFLAGS: 00000293 ORIG_RAX: 0000000000000012
2022-01-11 03:17:07 +08:00 <6> [59846.279679] RAX: ffffffffffffffda RBX: 0000000000000012 RCX: 00007f1b2aa8b04f
2022-01-11 03:17:07 +08:00 <6> [59846.286829] RDX: 0000000000000080 RSI: 000055edd75b8000 RDI: 0000000000000012
2022-01-11 03:17:07 +08:00 <6> [59846.293977] RBP: 000055edd75b8000 R08: 0000000000000000 R09: 0000000000000000
2022-01-11 03:17:07 +08:00 <6> [59846.301120] R10: 00000000000f6100 R11: 0000000000000293 R12: 0000000000000080
2022-01-11 03:17:07 +08:00 <6> [59846.308265] R13: 00000000000f6100 R14: 000055edd4d50b80 R15: 00000000000f6100
2022-01-11 03:17:07 +08:00 <3> [59846.315562] INFO: task ftdc:14484 blocked for more than 123 seconds.
2022-01-11 03:17:07 +08:00 <3> [59846.321938]       Tainted: P     U     O      5.10.60-qnap #1
2022-01-11 03:17:07 +08:00 <3> [59846.327697] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
2022-01-11 03:17:07 +08:00 <6> [59846.335541] task:ftdc            state:D stack:    0 pid:14484 ppid: 11331 flags:0x00000000
2022-01-11 03:17:07 +08:00 <6> [59846.343906] Call Trace:
2022-01-11 03:17:07 +08:00 <6> [59846.346372]  __schedule+0x1dd/0x610
2022-01-11 03:17:07 +08:00 <6> [59846.349910]  schedule+0x41/0xa0
2022-01-11 03:17:07 +08:00 <6> [59846.353076]  percpu_rwsem_wait+0xd3/0x180
2022-01-11 03:17:07 +08:00 <6> [59846.357103]  ? percpu_up_write+0x30/0x30
2022-01-11 03:17:07 +08:00 <6> [59846.361039]  __percpu_down_read+0x53/0x60
2022-01-11 03:17:07 +08:00 <6> [59846.365064]  mnt_want_write+0x60/0x80
2022-01-11 03:17:07 +08:00 <6> [59846.368753]  path_openat+0x42e/0xeb0
2022-01-11 03:17:07 +08:00 <6> [59846.372346]  ? release_pages+0x23e/0x300
2022-01-11 03:17:07 +08:00 <6> [59846.376284]  do_filp_open+0x94/0x110
2022-01-11 03:17:07 +08:00 <6> [59846.379879]  ? do_sys_openat2+0x1f3/0x390
2022-01-11 03:17:07 +08:00 <6> [59846.383914]  do_sys_openat2+0x1f3/0x390
2022-01-11 03:17:07 +08:00 <6> [59846.387769]  ? hrtimer_interrupt+0x14d/0x260
2022-01-11 03:17:07 +08:00 <6> [59846.392054]  do_sys_open+0x55/0x70
2022-01-11 03:17:07 +08:00 <6> [59846.395487]  do_syscall_64+0x2d/0x40
2022-01-11 03:17:07 +08:00 <6> [59846.399081]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
2022-01-11 03:17:07 +08:00 <6> [59846.404144] RIP: 0033:0x7f1b2a797d19
2022-01-11 03:17:07 +08:00 <6> [59846.407730] RSP: 002b:00007f1b1c7584b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
2022-01-11 03:17:07 +08:00 <6> [59846.415311] RAX: ffffffffffffffda RBX: 000055edd9aadb40 RCX: 00007f1b2a797d19
2022-01-11 03:17:07 +08:00 <6> [59846.422460] RDX: 0000000000000241 RSI: 000055edd4b189e0 RDI: 00000000ffffff9c
2022-01-11 03:17:07 +08:00 <6> [59846.429603] RBP: 000055edd0d967dc R08: 0000000000000000 R09: 000055edd0d967dd
2022-01-11 03:17:07 +08:00 <6> [59846.436748] R10: 00000000000001b6 R11: 0000000000000293 R12: 0000000000000004
2022-01-11 03:17:07 +08:00 <6> [59846.443892] R13: 000055edd0d967db R14: 000055edd1b76048 R15: 000055edd1b75a10
```

首先是几条连续的`ext2 filesystem being mounted at /tmp/nasconfig_tmp supports timestamps until 2038`信息，表示连续进行了一些`mount`，然后是若干程序严重卡住的信息（blocked for more than 123 seconds），以及一些相关的堆栈、十六进制信息等。

```
INFO: task manager_svc:12583 blocked for more than 123 seconds.
Tainted: P     U     O      5.10.60-qnap #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message
```

容易查出来`blocked for more than 123 seconds`是内存脏数据太多，来不及写到磁盘而撑爆缓存的消息，说明此时突然出现了大量的IO或者内存占用，但`123 seconds`说明这已经是死机两分钟之后了。而这个条消息与上面的大量`mount`之间似乎没有有用信息了。

**其实还有，但我当时没有想到。**

当时我想的是，书到用时方恨少，也许可以通过一些调试办法找原因，但是太难了。`crontab`也没发现与这个时间相关联的东西。

## 外援

结果威联通的回复比我想的快，午饭过后就看到了邮件，很直白的让我：

```
> 把区域设置修改为“全球”
> 禁用再启用一下“Malware Remover”
> 再把区域设置改回去
```

这个自信的语气听起来很靠谱，我赶紧去找被遗忘了的“Malware Remover”，先打开看看，发现打开后居然是个错误页面，这就更有谱了，照邮件里面说的做一遍，发现“Malware Remover”能打开了，显示我设置了一个每晚一点钟的的病毒扫描。

试着手动执行了一次错误扫描，没出问题，没有十分卡顿。再去生成一份详细日志，发现最新日志里面出现了一系列的`ext2 filesystem being mounted at /tmp/nasconfig_tmp supports timestamps until 2038 (0x7fffffff)`，但没有后续的IO问题报告。

并且，不知道是不是心理作用，总感觉响应比前几天灵敏了一些。

就这样过了24小时，没有再次死机，功能都正常，这个问题算是解决了。

复盘的话，大概是`Malware Remover`在最近的某次更新里面出了什么问题，同时，设定在一点的扫描在遇到其他定时任务时会自动让路，或者由于更新的问题导致`Malware Remover`在夜里三四点更新后会再扫描一次，最终导致了这一系列似乎随机又似乎有规律的死机事件。

## 失误总结

以下失误，都是从当时的信息出发应该能够做到的，但没有做到，拖延了排错进程。

1. 寻找定时任务的时候，没有检查`Malware Remover`，否则应该可以更早发现这个APP有问题——不过试了一下，从那个错误信息也搜不到特别有用的东西；
2. 发现“威联通挖矿病毒”的消息的时候，本应该手动拿`Malware Remover`查一下，但实际上只是按消息内容确认了没有可疑文件；当然这里有威联通的锅，在应用商店卖`McAfee`，大家当然本能觉得`Malware Remover`不是什么好货。
3. 发现死机与连串`ext2 filesystem being mounted`的相关性后，在日志中搜`"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message`发现特异性很强，只出现了四组，而`ext2 filesystem being mounted`则散布的比较多，就没有深入挖掘。实际上，`ext2 filesystem being mounted`虽然很多，但连串的则只有在`Malware Remover`运行时才能发现，大概每天一两次。如果进一步按连串消息的出现时间去对应系统事件日志，应该可以发现这种日志代表`Malware Remover`的后台运行。
4. 但是，即使发现了问题与`Malware Remover`相关，网上搜不到也想不到改区域-禁用-启用-改回来这种骚操作。下次一有问题就立即叫技术支持，劳资付过钱的。

## 淦！

刚才写完文章，去看了一眼威联通的官网，结果居然在页面顶部看到一个红色弹窗，没有标日期，但肯定是最近的（否则不会在其他不相干页面弹窗）：

```
如何解決 Malware Remover 服務更新所造成的 NAS 連線問題
近日 Malware Remover 服務更新導致部分 QNAP NAS 出現連線異常問題。使用者如於 Malware Remover 的設定選項中啟用「自動更新」將受此問題影響。我們已經再次調整 Malware Remover 服務並修正此問題。

如您的 NAS 完成 Malware Remover 服務更新後發生停止回應或是無法存取的問題，請依照以下步驟手動重啟您的 NAS：

持續按壓電源鍵直到 NAS 完成斷電關機
再次按壓電源鍵重新啟動 NAS
受影響的 NAS 經過手動重啟後即可恢復正常運作。如果仍有異常情況或疑問，請聯繫 QNAP 技術支援尋求協助。

```

威联通你二大爷……

不过即使我早看到了这个通知，强关再打开这种操作仍然解决不了我的问题，还是需要改区域-禁用再启用-再把区域改回来这种骚操作。之于为啥不把这个操作放到通知里面，大概是因为太丢人吧……