fix: init v8 platform once on main thread (#20495)

This is a mitigation for segfaults happening in V8 on CPU with MPK
(memory protected keys).

After much trail and error we found that unless V8 platform is
initialized on main thread the segfaults start appears once JIT 
kicks in. "deno test" and "deno bench" were affected by
this problem.

Fixes https://github.com/denoland/deno/issues/19926
Fixes https://github.com/denoland/deno/issues/20243
Fixes https://github.com/denoland/deno/issues/20450

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/cli/main.rs b/cli/main.rs
index 9044a14da..df5dd0b26 100644
--- a/cli/main.rs
+++ b/cli/main.rs
@@ -264,6 +264,10 @@ pub fn main() {
 
   let args: Vec<String> = env::args().collect();
 
+  // NOTE(lucacasonato): due to new PKU feature introduced in V8 11.6 we need to
+  // initalize the V8 platform on a parent thread of all threads that will spawn
+  // V8 isolates.
+
   let future = async move {
     let current_exe_path = current_exe()?;
     let standalone_res =
@@ -296,6 +300,7 @@ pub fn main() {
       _ => vec![],
     };
     init_v8_flags(&default_v8_flags, &flags.v8_flags, get_v8_flags_from_env());
+    deno_core::JsRuntime::init_platform(None);
 
     util::logger::init(flags.log_level);