fix: Fix segmentation fault in tests on CPUs with PKU support

core/Cargo.toml

@@ -19,6 +19,7 @@ include_icu_data = []
 v8_use_custom_libcxx = ["v8/use_custom_libcxx"]
 include_js_files_for_snapshotting = []
 unsafe_runtime_options = []
+testing = []
 
 # Use the old, slower (but better tested) JoinSet driver
 op_driver_joinset = []

core/runtime/jsruntime.rs

@@ -413,8 +413,16 @@ fn v8_init(
   };
   v8::V8::set_flags_from_string(&flags);
 
-  let v8_platform = v8_platform
-    .unwrap_or_else(|| v8::new_default_platform(0, false).make_shared());
+  let v8_platform = v8_platform.unwrap_or_else(|| {
+    if cfg!(any(test, feature = "testing")) {
+      // We don't want to use the default platform in tests, because it
+      // uses memory protection keys which break multi-threaded tests.
+      v8::new_unprotected_default_platform(0, false)
+    } else {
+      v8::new_default_platform(0, false)
+    }
+    .make_shared()
+  });
   v8::V8::initialize_platform(v8_platform.clone());
   v8::V8::initialize();
 

serde_v8/magic/v8slice.rs

@@ -107,7 +107,8 @@ where
     static V8_ONCE: std::sync::Once = std::sync::Once::new();
 
     V8_ONCE.call_once(|| {
-      let platform = v8::new_default_platform(0, false).make_shared();
+      let platform =
+        v8::new_unprotected_default_platform(0, false).make_shared();
       v8::V8::initialize_platform(platform);
       v8::V8::initialize();
     });

serde_v8/utils.rs

@@ -11,7 +11,7 @@ pub fn js_exec<'s>(
 }
 
 pub fn v8_init() {
-  let platform = v8::new_default_platform(0, false).make_shared();
+  let platform = v8::new_unprotected_default_platform(0, false).make_shared();
   v8::V8::initialize_platform(platform);
   v8::V8::initialize();
 }

testing/Cargo.toml

@@ -15,6 +15,7 @@ path = "./lib.rs"
 
 [dev-dependencies]
 deno_core.workspace = true
+deno_core.features = ["testing"]
 pretty_assertions.workspace = true
 prettyplease.workspace = true
 testing_macros.workspace = true