RFR(s): 8074860: Structured Exception Catcher missing around CreateJavaVM on Windows

[Thomas Stüfe]

Hi Daniel,

thanks a lot for the review!

On Wed, Apr 1, 2015 at 3:18 AM, Daniel D. Daugherty <
daniel.daugherty at oracle.com> wrote:

> On 3/11/15 9:40 AM, Thomas Stüfe wrote:
>
>> Hi all,
>>
>> please review this smallish change:
>>
>> webrev:
>> http://cr.openjdk.java.net/~stuefe/webrevs/8074860/webrev.01/webrev/
>>
>
> nit general comment - please update copyright year to 2015 as needed
>
>
I can't, I am not working for Oracle.



> src/cpu/x86/vm/vm_version_x86.cpp
> src/os/windows/vm/os_windows.inline.hpp
>     kvn added this use of CALL_TEST_FUNC_WITH_WRAPPER_IF_NEEDED().
>     Looks like a clean removal to me.
>
> src/os/windows/vm/os_windows.cpp
> src/os/windows/vm/os_windows.hpp
>     I added call_test_func_with_wrapper() back in 2013.
>     Looks like a clean removal to me.
>
> src/share/vm/prims/jni.cpp
>     nit line 4047 - delete extra blank line
>
>     The new JNI_CreateJavaVM() wrapper does the same thing as
>     call_test_func_with_wrapper() that I added back in 2013.
>
> Thumbs up!
>
> Dan
>
>
@David: when you find time, you could push this now. Also, I am now jdk9
author :-) so you can just use "stuefe". Thank you!

Kind Regards, Thomas



>
>  bug:  https://bugs.openjdk.java.net/browse/JDK-8074860
>>
>> This change adds SEH guards around JNI_CreateJavaVM(). Without the change,
>> on Windows, the VM initialization runs without crash protection: crashes
>> will terminate VM immediately without writing an error log; also, any
>> techniques relying on signals will not work, e.g. SafeFetch().
>>
>> This was partly solved before on a case-by-case base by wrapping code
>> sections which may crash in their own __try/__except wrappers - e.g. CPU
>> feature probing.
>>
>> The change guards the whole of JNI_CreateJavaVM invocation in
>> __try/__except. Unfortunately, for that to compile, I needed to introduce
>> a
>> wrapper around JNI_CreateJavaVM and move the whole of JNI_CreateJavaVM to
>> a
>> new function "JNI_CreateJavaVM_inner".
>>
>> This fix also gets rid of various workarounds which were used before to
>> guard code sections.
>>
>> Thanks for reviewing!
>>
>> Oh, on a side note: I tried to figure out if threads which are attached
>> from the outside via JNI AttachCurrentThread() are in any way guarded with
>> SEH protection. Newly created threads are guarded because they run thru
>> java_start() in os_windows.cpp, which adds SEH guards to all frames below.
>> But for attached threads, I did not find any SEH guards - or maybe I am
>> blind? What does that mean for java code running inside attached threads?
>>
>> Regards,
>>
>> Thomas Stuefe
>>
>>
>