[12] RFR(xs): 8215947: JVM crash with -XX:+DumpSharedSpaces

[Lois Foltan]

Looks good Calvin!

Lois

On 1/3/2019 1:13 PM, Calvin Cheung wrote:
> bug: https://bugs.openjdk.java.net/browse/JDK-8215947
>
> webrev: http://cr.openjdk.java.net/~ccheung/8215947/webrev.00/
>
> The bug was filed as confidential, the crash is as follows:
>
> $ java -XX:+DumpSharedSpaces
> narrow_klass_base = 0x0000000800000000, narrow_klass_shift = 3
> Allocated temporary class space: 1073741824 bytes at 0x00000008c0000000
> Allocated shared space: 3221225472 bytes at 0x0000000800000000
> Loading classes to share ...
> Loading classes to share: done.
> Rewriting and linking classes ...
> Rewriting and linking classes: done
> Number of classes 1229
>     instance classes = 1168
>     obj array classes = 53
>     type array classes = 8
> Updating ConstMethods ... done.
> Removing unshareable information ... #
> # A fatal error has been detected by the Java Runtime Environment:
> #
> # Internal Error (instanceKlass.cpp:2288), pid=28024, tid=28031
> # guarantee(_dep_context == DependencyContext::EMPTY) failed: must be
> #
> # JRE version: Java(TM) SE Runtime Environment (11.0.2+7) (build
> 11.0.2+7-LTS)
> # Java VM: Java HotSpot(TM) 64-Bit Server VM (11.0.2+7-LTS, mixed mode,
> tiered, compressed oops, g1 gc, linux-amd64)
>
> We currently disable JIT compilation in arguments.cpp if the user 
> specifies -Xshare:dump.
>     } else if (match_option(option, "-Xshare:dump")) {
>       if (FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true) != 
> JVMFlag::SUCCESS) {
>         return JNI_EINVAL;
>       }
>       set_mode_flags(_int); // Prevent compilation, which creates objects
>
> The proper way to create a shared archive is by specifying 
> -Xshare:dump instead of -XX:+DumpSharedSpaces.
> This fix is to disable compilation if DumpSharedSpaces is specified in 
> Arguments::finalize_vm_init_args().
>
> Testing: ran mach5 hs-tier{1,2,3} tests.
>
> thanks,
> Calvin