Fix shutdown with multiple unhandled HW exceptions

src/coreclr/pal/src/exception/seh.cpp

@@ -109,7 +109,7 @@ SEHCleanup()
 {
     TRACE("Cleaning up SEH\n");
 
-    SEHCleanupSignals();
+    SEHCleanupSignals(false /* isChildProcess */);
 }
 
 /*++

src/coreclr/pal/src/exception/signal.cpp

@@ -279,7 +279,7 @@ Function :
     Restore default signal handlers
 
 Parameters :
-    None
+    isChildProcess - indicates that it is called from a child process fork
 
     (no return value)
 
@@ -288,34 +288,42 @@ reason for this function is that during PAL_Terminate, we reach a point where
 SEH isn't possible anymore (handle manager is off, etc). Past that point,
 we can't avoid crashing on a signal.
 --*/
-void SEHCleanupSignals()
+void SEHCleanupSignals(bool isChildProcess)
 {
     TRACE("Restoring default signal handlers\n");
 
-    if (g_registered_signal_handlers)
+    if (isChildProcess)
     {
-        restore_signal(SIGILL, &g_previous_sigill);
+        if (g_registered_signal_handlers)
+        {
+            restore_signal(SIGILL, &g_previous_sigill);
 #if !HAVE_MACH_EXCEPTIONS
-        restore_signal(SIGTRAP, &g_previous_sigtrap);
+            restore_signal(SIGTRAP, &g_previous_sigtrap);
 #endif
-        restore_signal(SIGFPE, &g_previous_sigfpe);
-        restore_signal(SIGBUS, &g_previous_sigbus);
-        restore_signal(SIGABRT, &g_previous_sigabrt);
-        restore_signal(SIGSEGV, &g_previous_sigsegv);
-        restore_signal(SIGINT, &g_previous_sigint);
-        restore_signal(SIGQUIT, &g_previous_sigquit);
-    }
+            restore_signal(SIGFPE, &g_previous_sigfpe);
+            restore_signal(SIGBUS, &g_previous_sigbus);
+            restore_signal(SIGSEGV, &g_previous_sigsegv);
+            restore_signal(SIGINT, &g_previous_sigint);
+            restore_signal(SIGQUIT, &g_previous_sigquit);
+        }
 
 #ifdef INJECT_ACTIVATION_SIGNAL
-    if (g_registered_activation_handler)
-    {
-        restore_signal(INJECT_ACTIVATION_SIGNAL, &g_previous_activation);
-    }
+        if (g_registered_activation_handler)
+        {
+            restore_signal(INJECT_ACTIVATION_SIGNAL, &g_previous_activation);
+        }
 #endif
 
-    if (g_registered_sigterm_handler)
+        if (g_registered_sigterm_handler)
+        {
+            restore_signal(SIGTERM, &g_previous_sigterm);
+        }
+    }
+
+    // Restore only the SIGABRT so that abort that ends up the process can actually end it
+    if (g_registered_signal_handlers)
     {
-        restore_signal(SIGTERM, &g_previous_sigterm);
+        restore_signal(SIGABRT, &g_previous_sigabrt);
     }
 }
 

src/coreclr/pal/src/include/pal/signal.hpp

@@ -112,10 +112,12 @@ Function :
     SEHCleanupSignals
 
     Restore default signal handlers
+Parameters :
+    isChildProcess - indicates that it is called from a child process fork
 
     (no parameters, no return value)
 --*/
-void SEHCleanupSignals();
+void SEHCleanupSignals(bool isChildProcess);
 
 /*++
 Function :

src/coreclr/pal/src/thread/process.cpp

@@ -2257,7 +2257,7 @@ PROCCreateCrashDump(
         if (g_createdumpCallback != nullptr)
         {
             // Remove the signal handlers inherited from the runtime process
-            SEHCleanupSignals();
+            SEHCleanupSignals(true /* isChildProcess */);
 
             // Call the statically linked createdump code
             g_createdumpCallback(argv.size(), argv.data());
@@ -2556,7 +2556,7 @@ PROCAbort(int signal, siginfo_t* siginfo)
 
     // Restore all signals; the SIGABORT handler to prevent recursion and
     // the others to prevent multiple core dumps from being generated.
-    SEHCleanupSignals();
+    SEHCleanupSignals(false /* isChildProcess */);
 
     // Abort the process after waiting for the core dump to complete
     abort();

src/tests/baseservices/exceptions/stackoverflow/stackoverflowtester.cs

@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.Runtime.InteropServices;
 using System.Text;
 using Xunit;
 
@@ -22,12 +23,27 @@ static void TestStackOverflow(string testName, string testArgs, out List<string>
             testProcess.StartInfo.Arguments = $"{Path.Combine(Directory.GetCurrentDirectory(), "..", testName, $"{testName}.dll")} {testArgs}";
             testProcess.StartInfo.UseShellExecute = false;
             testProcess.StartInfo.RedirectStandardError = true;
+            testProcess.StartInfo.Environment.Add("DOTNET_DbgEnableMiniDump", "0");
+            bool endOfStackTrace = false;
+
             testProcess.ErrorDataReceived += (sender, line) => 
             {
                 Console.WriteLine($"\"{line.Data}\"");
-                if (!string.IsNullOrEmpty(line.Data))
+                if (!endOfStackTrace && !string.IsNullOrEmpty(line.Data))
                 {
-                    lines.Add(line.Data);
+                    // Store lines only till the end of the stack trace.
+                    // In the CI it can also contain lines with createdump info.
+                    if (line.Data.StartsWith("Stack overflow.") ||
+                        line.Data.StartsWith("Repeated ") ||
+                        line.Data.StartsWith("------") ||
+                        line.Data.StartsWith("   at "))
+                    {
+                        lines.Add(line.Data);
+                    }
+                    else
+                    {
+                        endOfStackTrace = true;
+                    }
                 }
             };
 
@@ -99,6 +115,15 @@ public static void TestStackOverflowSmallFrameMainThread()
         [Fact]
         public static void TestStackOverflowLargeFrameMainThread()
         {
+            if ((RuntimeInformation.ProcessArchitecture == Architecture.Arm64) &&
+                ((Environment.OSVersion.Platform == PlatformID.Unix) || (Environment.OSVersion.Platform == PlatformID.MacOSX)))
+            {
+                // Disabled on Unix ARM64 due to https://github.com/dotnet/runtime/issues/13519
+                // The current stack probing doesn't move the stack pointer and so the runtime sometimes cannot
+                // recognize the underlying sigsegv as stack overflow when it probes too far from SP.
+                return;
+            }
+
             TestStackOverflow("stackoverflow", "largeframe main", out List<string> lines);
 
             if (!lines[lines.Count - 1].EndsWith("at TestStackOverflow.Program.Main(System.String[])"))
@@ -156,6 +181,15 @@ public static void TestStackOverflowSmallFrameSecondaryThread()
         [Fact]
         public static void TestStackOverflowLargeFrameSecondaryThread()
         {
+            if ((RuntimeInformation.ProcessArchitecture == Architecture.Arm64) &&
+                ((Environment.OSVersion.Platform == PlatformID.Unix) || (Environment.OSVersion.Platform == PlatformID.MacOSX)))
+            {
+                // Disabled on Unix ARM64 due to https://github.com/dotnet/runtime/issues/13519
+                // The current stack probing doesn't move the stack pointer and so the runtime sometimes cannot
+                // recognize the underlying sigsegv as stack overflow when it probes too far from SP.
+                return;
+            }
+
             TestStackOverflow("stackoverflow", "largeframe secondary", out List<string> lines);
 
             if (!lines.Exists(elem => elem.EndsWith("at TestStackOverflow.Program.Test(Boolean)")))

src/tests/issues.targets

@@ -89,9 +89,6 @@
 
     <!-- All Unix targets  on CoreCLR Runtime -->
     <ItemGroup Condition="'$(XunitTestBinBase)' != '' and '$(TargetsWindows)' != 'true' and '$(RuntimeFlavor)' == 'coreclr' ">
-        <ExcludeList Include="$(XunitTestBinBase)/baseservices/exceptions/stackoverflow/stackoverflowtester/*">
-            <Issue>https://github.com/dotnet/runtime/issues/46175</Issue>
-        </ExcludeList>
         <ExcludeList Include="$(XunitTestBinBase)/baseservices/typeequivalence/signatures/nopiatestil/*">
             <Issue>CoreCLR doesn't support type equivalence on Unix</Issue>
         </ExcludeList>