On Wed, 3 Mar 2021 15:57:13 GMT, Gerard Ziemski <gziem...@openjdk.org> wrote:
>> src/hotspot/os_cpu/bsd_aarch64/os_bsd_aarch64.cpp line 207: >> >>> 205: // Enable WXWrite: this function is called by the signal handler at >>> arbitrary >>> 206: // point of execution. >>> 207: ThreadWXEnable wx(WXWrite, thread); >> >> Note that `thread` can be NULL here if the signal handler is running in a >> non-attached thread. If we then perform: >> `ThreadWXEnable(WXMode new_mode, Thread* thread = NULL) : >> _thread(thread ? thread : Thread::current()),` >> we call Thread::current() on a non-attached thread and that will >> assert/crash if we get NULL. Either avoid using WX when the thread is NULL, >> or else change to use Thread::current_or_null_safe() and ensure all uses >> have a NULL check. > >> Note that `thread` can be NULL here if the signal handler is running in a >> non-attached thread. If we then perform: >> `ThreadWXEnable(WXMode new_mode, Thread* thread = NULL) : _thread(thread ? >> thread : Thread::current()),` >> we call Thread::current() on a non-attached thread and that will >> assert/crash if we get NULL. Either avoid using WX when the thread is NULL, >> or else change to use Thread::current_or_null_safe() and ensure all uses >> have a NULL check. > > https://bugs.openjdk.java.net/browse/JDK-8262903 tracks this issue. Thanks for report and analysis! I fixed this in https://github.com/openjdk/jdk/pull/2200/commits/f6fb01b24f525e578692a1c6f2ff0a55b8233576 ------------- PR: https://git.openjdk.java.net/jdk/pull/2200
