[GR-74243] Add faulthandler self-signaling functions.

timfel · timfel · commit 1eafc0807418 · 2026-03-24T14:46:19.000Z
PullRequest: graalpython/4347
diff --git a/graalpython/com.oracle.graal.python.test/src/tests/test_traceback.py b/graalpython/com.oracle.graal.python.test/src/tests/test_traceback.py
@@ -37,6 +37,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 import ast
+import subprocess
 import sys
 
 
@@ -659,6 +660,34 @@ def test_faulthandler_many_threads():
             assert len(ids) == 1, f"Interleaved output detected in block {header!r} with multiple thread func ids: {ids}"
 
 
+def test_faulthandler_sigsegv_builtin():
+    import faulthandler
+
+    try:
+        if not __graalpython__.is_native or __graalpython__.posix_module_backend() == "java":
+            return
+    except NameError:
+        pass # CPython
+
+    def assert_fatal_faulthandler_call(name, *args):
+        assert hasattr(faulthandler, name)
+        code = f"import faulthandler; faulthandler.{name}({', '.join(map(repr, args))})"
+        proc = subprocess.run(
+            [sys.executable, "-c", code],
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
+        )
+        assert proc.returncode != 0
+        assert proc.returncode != 1, (
+            f"expected fatal signal path for faulthandler.{name}{args}, "
+            f"got regular Python error exit {proc.returncode}"
+        )
+
+    for release_gil in (False, True):
+        assert_fatal_faulthandler_call("_sigsegv", release_gil)
+    assert_fatal_faulthandler_call("_sigabrt")
+
+
 def test_location_from_ast():
     m = compile("a = 1\nx", "<stdin>", "exec", flags=ast.PyCF_ONLY_AST)
 
diff --git a/graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_concurrent_futures.txt b/graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_concurrent_futures.txt
@@ -7,7 +7,6 @@ test.test_concurrent_futures.test_as_completed.ThreadPoolAsCompletedTest.test_co
 test.test_concurrent_futures.test_as_completed.ThreadPoolAsCompletedTest.test_duplicate_futures @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_as_completed.ThreadPoolAsCompletedTest.test_future_times_out @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_as_completed.ThreadPoolAsCompletedTest.test_no_timeout @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
-test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_crash_at_task_unpickle @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_error_at_task_pickle @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_error_at_task_unpickle @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_error_during_func_exec_on_worker @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
@@ -18,6 +17,7 @@ test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.
 test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_exit_during_result_pickle_on_worker @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_exit_during_result_unpickle_in_result_handler @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 # Transiently times out GR-65714
+!test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_crash_at_task_unpickle
 !test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_gh105829_should_not_deadlock_if_wakeup_pipe_full
 !test.test_concurrent_futures.test_deadlock.ProcessPoolSpawnExecutorDeadlockTest.test_shutdown_deadlock_pickle
 !test.test_concurrent_futures.test_future.FutureTests.test_cancel
diff --git a/graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_faulthandler.txt b/graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_faulthandler.txt
@@ -1,7 +1,7 @@
 test.test_faulthandler.FaultHandlerTests.test_cancel_later_without_dump_traceback_later @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
-test.test_faulthandler.FaultHandlerTests.test_disable @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_faulthandler.FaultHandlerTests.test_disabled_by_default @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
 test.test_faulthandler.FaultHandlerTests.test_is_enabled @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
 # Disabled since signaling isn't stable during parallel tests
+!test.test_faulthandler.FaultHandlerTests.test_disable
 !test.test_faulthandler.FaultHandlerTests.test_sigbus
 !test.test_faulthandler.FaultHandlerTests.test_sigill
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/FaulthandlerModuleBuiltins.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/FaulthandlerModuleBuiltins.java
@@ -69,16 +69,21 @@
 import com.oracle.graal.python.lib.PyTimeFromObjectNode;
 import com.oracle.graal.python.lib.PyTimeFromObjectNode.RoundType;
 import com.oracle.graal.python.nodes.ErrorMessages;
+import com.oracle.graal.python.nodes.PConstructAndRaiseNode;
 import com.oracle.graal.python.nodes.PRaiseNode;
 import com.oracle.graal.python.nodes.function.PythonBuiltinBaseNode;
 import com.oracle.graal.python.nodes.function.PythonBuiltinNode;
 import com.oracle.graal.python.nodes.function.builtins.PythonClinicBuiltinNode;
 import com.oracle.graal.python.nodes.function.builtins.PythonTernaryBuiltinNode;
+import com.oracle.graal.python.nodes.function.builtins.PythonUnaryClinicBuiltinNode;
 import com.oracle.graal.python.nodes.function.builtins.PythonUnaryBuiltinNode;
 import com.oracle.graal.python.nodes.function.builtins.clinic.ArgumentClinicProvider;
 import com.oracle.graal.python.runtime.ExecutionContext.BoundaryCallContext;
+import com.oracle.graal.python.runtime.GilNode;
 import com.oracle.graal.python.runtime.IndirectCallData.BoundaryCallData;
 import com.oracle.graal.python.runtime.PosixSupportLibrary;
+import com.oracle.graal.python.runtime.PosixSupportLibrary.PosixException;
+import com.oracle.graal.python.runtime.PosixSupportLibrary.UnsupportedPosixFeatureException;
 import com.oracle.graal.python.runtime.PythonContext;
 import com.oracle.graal.python.runtime.PythonOptions;
 import com.oracle.graal.python.runtime.exception.ExceptionUtils;
@@ -95,6 +100,7 @@
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.exception.AbstractTruffleException;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
 import com.oracle.truffle.api.strings.TruffleString;
 
@@ -235,6 +241,62 @@ static int fileno(VirtualFrame frame, Node inliningTarget, Object file,
         }
     }
 
+    @Builtin(name = "_sigsegv", minNumOfPositionalArgs = 0, parameterNames = {"release_gil"})
+    @ArgumentClinic(name = "release_gil", conversion = ArgumentClinic.ClinicConversion.Boolean, defaultValue = "false")
+    @GenerateNodeFactory
+    abstract static class SigSegvNode extends PythonUnaryClinicBuiltinNode {
+        @Specialization
+        static PNone doIt(VirtualFrame frame, boolean releaseGil,
+                        @Bind PythonContext context,
+                        @Bind Node inliningTarget,
+                        @CachedLibrary("context.getPosixSupport()") PosixSupportLibrary posixLib,
+                        @Cached GilNode gil,
+                        @Cached PConstructAndRaiseNode.Lazy constructAndRaiseNode) {
+            return raiseFatalSignal(frame, context, inliningTarget, posixLib, gil, constructAndRaiseNode, "SEGV", releaseGil);
+        }
+
+        @Override
+        protected ArgumentClinicProvider getArgumentClinic() {
+            return FaulthandlerModuleBuiltinsClinicProviders.SigSegvNodeClinicProviderGen.INSTANCE;
+        }
+    }
+
+    @Builtin(name = "_sigabrt", minNumOfPositionalArgs = 0)
+    @GenerateNodeFactory
+    abstract static class SigAbrtNode extends PythonBuiltinNode {
+        @Specialization
+        static PNone doIt(VirtualFrame frame,
+                        @Bind PythonContext context,
+                        @Bind Node inliningTarget,
+                        @CachedLibrary("context.getPosixSupport()") PosixSupportLibrary posixLib,
+                        @Cached GilNode gil,
+                        @Cached PConstructAndRaiseNode.Lazy constructAndRaiseNode) {
+            return raiseFatalSignal(frame, context, inliningTarget, posixLib, gil, constructAndRaiseNode, "ABRT", false);
+        }
+    }
+
+    private static PNone raiseFatalSignal(VirtualFrame frame, PythonContext context, Node inliningTarget, PosixSupportLibrary posixLib, GilNode gil,
+                    PConstructAndRaiseNode.Lazy constructAndRaiseNode, String signalName, boolean releaseGil) {
+        try {
+            int signum = SignalModuleBuiltins.signalFromName(context, signalName);
+            if (releaseGil) {
+                gil.release(true);
+            }
+            try {
+                posixLib.signalSelf(context.getPosixSupport(), signum);
+            } finally {
+                if (releaseGil) {
+                    gil.acquire();
+                }
+            }
+        } catch (PosixException e) {
+            throw constructAndRaiseNode.get(inliningTarget).raiseOSErrorFromPosixException(frame, e);
+        } catch (UnsupportedPosixFeatureException e) {
+            throw constructAndRaiseNode.get(inliningTarget).raiseOSErrorUnsupported(frame, e);
+        }
+        return PNone.NONE;
+    }
+
     @Builtin(name = "dump_traceback_later", minNumOfPositionalArgs = 2, declaresExplicitSelf = true, parameterNames = {"$mod", "timeout", "repeat", "file", "exit"})
     @ArgumentClinic(name = "repeat", conversion = ArgumentClinic.ClinicConversion.IntToBoolean, defaultValue = "false")
     @ArgumentClinic(name = "exit", conversion = ArgumentClinic.ClinicConversion.IntToBoolean, defaultValue = "false")
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/EmulatedPosixSupport.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/EmulatedPosixSupport.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -2014,6 +2014,12 @@ public void kill(long pid, int signal,
         }
     }
 
+    @ExportMessage
+    @SuppressWarnings("static-method")
+    public void signalSelf(int signal) {
+        throw createUnsupportedFeature("signalSelf");
+    }
+
     @ExportMessage
     @SuppressWarnings("static-method")
     public long killpg(long pgid, int signal) {
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/LoggingPosixSupport.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/LoggingPosixSupport.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -752,6 +752,17 @@ final void kill(long pid, int signal,
         }
     }
 
+    @ExportMessage
+    final void signalSelf(int signal,
+                    @CachedLibrary("this.delegate") PosixSupportLibrary lib) throws PosixException {
+        logEnter("signalSelf", "%d", signal);
+        try {
+            lib.signalSelf(delegate, signal);
+        } catch (PosixException e) {
+            throw logException("signalSelf", e);
+        }
+    }
+
     @ExportMessage
     final void killpg(long pgid, int signal,
                     @CachedLibrary("this.delegate") PosixSupportLibrary lib) throws PosixException {
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/NFIPosixSupport.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/NFIPosixSupport.java
@@ -89,6 +89,7 @@
 import java.util.concurrent.atomic.AtomicReferenceArray;
 import java.util.logging.Level;
 
+import org.graalvm.nativeimage.ImageInfo;
 import com.oracle.graal.python.PythonLanguage;
 import com.oracle.graal.python.annotations.PythonOS;
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
@@ -229,6 +230,7 @@ private enum PosixNativeFunction {
         get_blocking("(sint32):sint32"),
         set_blocking("(sint32, sint32):sint32"),
         get_terminal_size("(sint32, [sint32]):sint32"),
+        signal_self("(sint32):sint32"),
         call_kill("(sint64, sint32):sint32"),
         call_killpg("(sint64, sint32):sint32"),
         call_waitpid("(sint64, [sint32], sint32):sint64"),
@@ -1164,6 +1166,18 @@ public void kill(long pid, int signal,
         }
     }
 
+    @ExportMessage
+    public void signalSelf(int signal,
+                    @Shared("invoke") @Cached InvokeNativeFunction invokeNode) throws PosixException {
+        if (!ImageInfo.inImageRuntimeCode()) {
+            throw new UnsupportedPosixFeatureException("self-signals are only supported in native standalone");
+        }
+        int res = invokeNode.callInt(this, PosixNativeFunction.signal_self, signal);
+        if (res == -1) {
+            throw getErrnoAndThrowPosixException(invokeNode);
+        }
+    }
+
     @ExportMessage
     public void killpg(long pgid, int signal,
                     @Shared("invoke") @Cached InvokeNativeFunction invokeNode) throws PosixException {
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PosixSupportLibrary.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PosixSupportLibrary.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -258,6 +258,8 @@ public abstract class PosixSupportLibrary extends Library {
 
     public abstract Object readlinkat(Object receiver, int dirFd, Object path) throws PosixException;
 
+    public abstract void signalSelf(Object receiver, int signal) throws PosixException;
+
     public abstract void kill(Object receiver, long pid, int signal) throws PosixException;
 
     public abstract void killpg(Object receiver, long pid, int signal) throws PosixException;
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PreInitPosixSupport.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PreInitPosixSupport.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -588,6 +588,13 @@ final Object readlinkat(int dirFd, Object path,
         return nativeLib.readlinkat(nativePosixSupport, dirFd, path);
     }
 
+    @ExportMessage
+    final void signalSelf(int signal,
+                    @CachedLibrary("this.nativePosixSupport") PosixSupportLibrary nativeLib) throws PosixException {
+        checkNotInPreInitialization();
+        nativeLib.signalSelf(nativePosixSupport, signal);
+    }
+
     @ExportMessage
     final void kill(long pid, int signal,
                     @CachedLibrary("this.nativePosixSupport") PosixSupportLibrary nativeLib) throws PosixException {
diff --git a/graalpython/python-libposix/src/posix.c b/graalpython/python-libposix/src/posix.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -77,6 +77,8 @@
 #include <unistd.h>
 #include <pwd.h>
 
+int32_t signal_self_segv(void);
+
 #ifdef __APPLE__
 #include <util.h>
 #else
@@ -602,6 +604,20 @@ int32_t call_kill(int64_t pid, int32_t signal) {
     return kill(pid, signal);
 }
 
+int32_t signal_self(int32_t signal) {
+    switch (signal) {
+        case SIGABRT:
+            abort();
+            break;
+        case SIGSEGV:
+            return signal_self_segv();
+        default:
+            errno = EINVAL;
+            return -1;
+    }
+    _exit(128 + signal);
+}
+
 int32_t call_killpg(int64_t pgid, int32_t signal) {
     return killpg(pgid, signal);
 }
diff --git a/graalpython/python-libposix/src/posix_signal_self_segv.c b/graalpython/python-libposix/src/posix_signal_self_segv.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * The Universal Permissive License (UPL), Version 1.0
+ *
+ * Subject to the condition set forth below, permission is hereby granted to any
+ * person obtaining a copy of this software, associated documentation and/or
+ * data (collectively the "Software"), free of charge and under any and all
+ * copyright rights in the Software, and any and all patent rights owned or
+ * freely licensable by each licensor hereunder covering either (i) the
+ * unmodified Software as contributed to or provided by such licensor, or (ii)
+ * the Larger Works (as defined below), to deal in both
+ *
+ * (a) the Software, and
+ *
+ * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
+ * one is included with the Software each a "Larger Work" to which the Software
+ * is contributed by such licensors),
+ *
+ * without restriction, including without limitation the rights to copy, create
+ * derivative works of, display, perform, and distribute the Software and make,
+ * use, sell, offer for sale, import, export, have made, and have sold the
+ * Software and the Larger Work(s), and to sublicense the foregoing rights on
+ * either these or other terms.
+ *
+ * This license is subject to the following condition:
+ *
+ * The above copyright notice and either this complete permission notice or at a
+ * minimum a reference to the UPL must be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stdint.h>
+
+#if defined(_MSC_VER)
+#pragma optimize("", off)
+#define SIGNAL_SELF_SEGV_ATTR __declspec(noinline)
+#elif defined(__clang__)
+#pragma clang optimize off
+#define SIGNAL_SELF_SEGV_ATTR __attribute__((optnone, noinline))
+#elif defined(__GNUC__)
+#define SIGNAL_SELF_SEGV_ATTR __attribute__((optimize("O0"), noinline, noclone))
+#else
+#define SIGNAL_SELF_SEGV_ATTR
+#endif
+
+/*
+ * Keep the deliberate SIGSEGV in its own translation unit and discourage
+ * inlining/optimization to minimize the optimizer's freedom around the
+ * undefined null-dereference below.
+ */
+SIGNAL_SELF_SEGV_ATTR int32_t signal_self_segv(void) {
+    volatile int *p = (volatile int *)(uintptr_t)0;
+    *p = 1;
+    return 0;
+}
+
+#if defined(_MSC_VER)
+#pragma optimize("", on)
+#elif defined(__clang__)
+#pragma clang optimize on
+#endif

Original file line number	Diff line number	Diff line change
`@@ -1,5 +1,5 @@`
`1`	`1`	`/*`
`2`		`- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.`
	`2`	`+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.`
`3`	`3`	`* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.`
`4`	`4`	`*`
`5`	`5`	`* The Universal Permissive License (UPL), Version 1.0`
`@@ -2014,6 +2014,12 @@ public void kill(long pid, int signal,`
`2014`	`2014`	`}`
`2015`	`2015`	`}`
`2016`	`2016`
	`2017`	`+ @ExportMessage`
	`2018`	`+ @SuppressWarnings("static-method")`
	`2019`	`+ public void signalSelf(int signal) {`
	`2020`	`+ throw createUnsupportedFeature("signalSelf");`
	`2021`	`+ }`
	`2022`	`+`
`2017`	`2023`	`@ExportMessage`
`2018`	`2024`	`@SuppressWarnings("static-method")`
`2019`	`2025`	`public long killpg(long pgid, int signal) {`