On Wed, 20 Aug 2025 17:31:22 GMT, Evgeny Astigeevich <eastigeev...@openjdk.org> wrote:
>> There is a race between `JvmtiClassFileReconstituter::copy_bytecodes` and >> `InstanceKlass::link_class_impl`. `InstanceKlass::link_class_impl` can be >> rewriting bytecodes. `JvmtiClassFileReconstituter::copy_bytecodes` will not >> restore them to the original ones because the flag `rewritten` is `false`. >> This will result in invalid bytecode. >> >> This PR adds a lock (`init_lock`) to the `copy_bytecodes` method to prevent >> reading bytecodes while they are being rewritten during class linking. >> >> Tested fastdebug and release builds: Linux x86_64 and arm64 >> - The reproducer from JDK-8277444 passed. >> - Tier1 - tier3 passed. > > Evgeny Astigeevich has updated the pull request incrementally with one > additional commit since the last revision: > > Add missing include runtime/synchronizer.hpp This seems like the correct fix. Forcing these APIs to link the class first would be a change in behavior and I assume it could cause linking-related exceptions to be thrown that the client might not expect. ------------- PR Comment: https://git.openjdk.org/jdk/pull/26863#issuecomment-3215539178
