deps: V8: cherry-pick 0c8b6e415c30

matinzd · danielleadams · commit 50e81ba0b8a4 · 2021-02-16T09:12:58.000-05:00
Original commit message: [mac][wasm] Work around MacOS 11.2 code page decommit failures MacOS 11.2 refuses to set "no access" permissions on memory that we previously used for JIT-compiled code. It is still unclear whether this is WAI on the part of the kernel. In the meantime, as a workaround, we use madvise(..., MADV_FREE_REUSABLE) instead of mprotect(..., NONE) when discarding code pages. This is inspired by what Chromium's gin platform does. Fixed: v8:11389 Change-Id: I866586932573b4253002436ae5eee4e0411c45fc Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2679688 Commit-Queue: Jakob Kummerow <jkummerow@chromium.org> Commit-Queue: Michael Lippautz <mlippautz@chromium.org> Auto-Submit: Jakob Kummerow <jkummerow@chromium.org> Reviewed-by: Michael Lippautz <mlippautz@chromium.org> Cr-Commit-Position: refs/heads/master@{#72559} Refs: v8/v8@0c8b6e4 Fixes: #37061 PR-URL: #37276 Reviewed-By: Michaël Zasso <targos@protonmail.com> Reviewed-By: Ash Cripps <acripps@redhat.com>
diff --git a/common.gypi b/common.gypi
@@ -36,7 +36,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.24',
+    'v8_embedder_string': '-node.25',
 
     ##### V8 defaults for Node.js #####
 
diff --git a/deps/v8/src/base/platform/platform-posix.cc b/deps/v8/src/base/platform/platform-posix.cc
@@ -414,6 +414,16 @@ bool OS::SetPermissions(void* address, size_t size, MemoryPermission access) {
 
   int prot = GetProtectionFromMemoryPermission(access);
   int ret = mprotect(address, size, prot);
+
+  // MacOS 11.2 on Apple Silicon refuses to switch permissions from
+  // rwx to none. Just use madvise instead.
+#if defined(V8_OS_MACOSX)
+  if (ret != 0 && access == OS::MemoryPermission::kNoAccess) {
+    ret = madvise(address, size, MADV_FREE_REUSABLE);
+    return ret == 0;
+  }
+#endif
+
   if (ret == 0 && access == OS::MemoryPermission::kNoAccess) {
     // This is advisory; ignore errors and continue execution.
     USE(DiscardSystemPages(address, size));
