记一次 .NET 某光放测试系统 崩溃分析
<h2 id="一背景">一：背景</h2><h3 id="1-讲故事">1. 讲故事</h3>
<p>微信好友里有位朋友找到我，说他部署在windows上的程序，用debug模式正常，但用 release 模式跑程序就崩溃，如果把程序切到 .NET6 的话又都正常，所以很迷茫，让我看看怎么回事，哈哈，这种问题直接抓dump分析就好了。</p>
<h2 id="二崩溃分析">二：崩溃分析</h2>
<h3 id="1-为什么会崩溃">1. 为什么会崩溃</h3>
<p>分析过崩溃程序的朋友应该知道，不管是托管还是非托管崩溃，先用 <code>!analyze -v</code> 命令开路，简化输出如下：</p>
<pre><code class="language-C#">
0:000> !analyze -v
*******************************************************************************
* *
* Exception Analysis *
* *
*******************************************************************************
CONTEXT:(.ecxr)
rax=0000000000000004 rbx=000001e34b283ec0 rcx=0000000000000228
rdx=0000000000000000 rsi=000001e34ac2f4e0 rdi=000001e34ab58e70
rip=00007ff95ac53659 rsp=0000007735d7e1c0 rbp=0000007735d7e1e0
r8=0000000000000000r9=000001e3464ba1c0 r10=0000000000000228
r11=0000000000000228 r12=0000000000000000 r13=000001e34880eae8
r14=000001e34ab58e70 r15=0000000000000008
iopl=0 nv up di pl nz na pe nc
cs=0000ss=0000ds=0000es=0000fs=0000gs=0000 efl=00000000
System_Private_CoreLib!System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw+0x39:
00007ff9`5ac53659 cc int 3
Resetting default scope
EXCEPTION_RECORD:(.exr -1)
ExceptionAddress: 00007ff95ac53659 (System_Private_CoreLib!System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw+0x0000000000000039)
ExceptionCode: e0434f4d (CLR exception)
ExceptionFlags: 00000000
NumberParameters: 0
...
</code></pre>
<p>从卦中的 <code>ExceptionCode: e0434f4d (CLR exception)</code> 来看，这是一个经典的托管异常，既然是托管异常，这个问题就比较简单了，使用 <code>!t</code> 找下到底是哪一个托管线程抛的，输出如下：</p>
<pre><code class="language-C#">
0:000> !t
ThreadCount: 15
UnstartedThread:0
BackgroundThread: 11
PendingThread: 0
DeadThread: 3
Hosted Runtime: no
Lock
DBG ID OSID ThreadOBJ State GC Mode GC Alloc Context Domain Count Apt Exception
0 1 81d8 000001E3464BA1C0 a6028 Preemptive000001E34ABA2340:000001E34ABA3D30 000001e347fc40b0 -00001 STA Prism.Ioc.ContainerResolutionException 000001e34a986608
6 2 448c 000001E34803A440 2b228 Preemptive000001E34A876980:000001E34A8784B0 000001e347fc40b0 -00001 MTA (Finalizer)
...
</code></pre>
<p>从卦中的 <code>Prism.Ioc.ContainerResolutionException</code> 来看，貌似是和 Prism 有关，接下来可以用 <code>!pe</code> 命令观察调用栈详情。</p>
<pre><code class="language-C#">
0:000> !pe
Exception object: 000001e34a986608
Exception type: Prism.Ioc.ContainerResolutionException
Message: An unexpected error occurred while resolving 'xxx.Views.LoginWindow'
InnerException: Unity.ResolutionFailedException, Use !PrintException 000001E34A986228 to see more.
StackTrace (generated):
SP IP Function
0000007735D668E0 00007FF95A64DEC8 Prism_Unity_Wpf!Prism.Unity.UnityContainerExtension.Resolve(System.Type, System.ValueTuple`2<System.Type,System.Object>[])+0x2a8
0000007735D7DC60 00007FF95A64DBFD Prism_Unity_Wpf!Prism.Unity.UnityContainerExtension.Resolve(System.Type)+0x3d
0000007735D7DCA0 00007FF95A64DB88 Prism!Prism.Ioc.IContainerProviderExtensions.Resolve[](Prism.Ioc.IContainerProvider)+0x48
0000007735D7DCF0 00007FF95A956742 xxx!xxx.App.InitializeShell(System.Windows.Window)+0x42
0000007735D7DD40 00007FF959B21148 Prism_Wpf!Prism.PrismApplicationBase.Initialize()+0x208
0000007735D7DDA0 00007FF959B20F17 xxx!xxx.App.<>n__0()+0x17
....
</code></pre>
<p>从卦象来看，这不是最原始的异常，言外之意就是下面还有子异常，也只有找到最里层的异常才能发现灾难的祸根，经过一层层的下钻，最后找到了最原始的异常，参考如下：</p>
<pre><code class="language-C#">
0:000> !PrintException /d 000001E34A97E940
Exception object: 000001e34a97e940
Exception type: System.PlatformNotSupportedException
Message: System.IO.Ports is currently only supported on Windows.
InnerException: <none>
StackTrace (generated):
SP IP Function
0000007735D7B580 00007FF95A9588E7 System_IO_Ports!System.IO.Ports.SerialPort.GetPortNames()+0x47
0000007735D7B5C0 00007FF95A958859 xxx!xxx.ViewModels.LoginWindowViewModel.RefreshComs()+0x19
0000007735D7B600 00007FF95A957FBC xxx!xxx.ViewModels.LoginWindowViewModel..ctor()+0x14c
0000007735D7B9D0 0000000000000000 System_Private_CoreLib!System.RuntimeMethodHandle.InvokeMethod(System.Object, Void**, System.Signature, Boolean)+0x46a770b0
0000007735D7B9D0 00007FF9B8C03106 System_Private_CoreLib!System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(System.Object, System.Reflection.BindingFlags)+0x36
StackTraceString: <none>
HResult: 80131539
</code></pre>
<p>从卦中来看是 <code>GetPortNames()</code> 方法抛出来的平台不支持异常，这就很迷惑了。</p>
<h3 id="2-为什么会平台不支持">2. 为什么会平台不支持</h3>
<p>了解 PlatformNotSupportedException 异常，只能寻找相关的源代码了，通过dnspy截图如下：</p>
<p><img src="https://img2024.cnblogs.com/blog/214741/202510/214741-20251023114415540-185125163.png" alt="" loading="lazy"></p>
<p>从卦中来看这是一个空方法，接下来拿这个异常在网上找下资料，看样子是这位朋友需要升级或者降级 system.io.ports 的版本，截图如下：</p>
<p><img src="https://img2024.cnblogs.com/blog/214741/202510/214741-20251023114415732-287926205.png" alt="" loading="lazy"></p>
<p>完整链接：https://learn.microsoft.com/en-us/answers/questions/1621393/system-io-ports-only-availble-on-windows-but-im-us</p>
<p>本来是很兴奋的，以为是类似多线程操控非 volatile 变量导致的debug和release行为不一致呢，结果是这玩意，害！</p>
<h2 id="三总结">三：总结</h2>
<p>本次故障相对比较简单，对我们这些老手来说简直是 1+1，但我们何尝不是从新手练过来的，所以本篇是初学者很好的一个练手素材。</p>
<img src="https://images.cnblogs.com/cnblogs_com/huangxincheng/345039/o_210929020104最新消息优惠促销公众号关注二维码.jpg" width="700" height="300" alt="图片名称" align="center"><br><br>
来源：https://www.cnblogs.com/huangxincheng/p/19160157
頁:
[1]