Request for review: 8001341/8004223: SIGSEGV in methodOopDesc::fast_exception_handler_bci_for(KlassHandle, int, Thread*)+0x3e9

[Jiangli Zhou]

Hi Chris,

Thanks for the review and suggestion! Will add a comment in 
src/share/vm/oops/method.hpp.

Thanks,
Jiangli


On 01/07/2013 02:34 PM, Christian Thalinger wrote:
> On Jan 7, 2013, at 12:30 PM, Jiangli Zhou<jiangli.zhou at oracle.com>  wrote:
>
>> Hi,
>>
>> Please review the fix for 8001341/8004223: SIGSEGV in methodOopDesc::fast_exception_handler_bci_for(KlassHandle,int,Thread*)+0x3e9.
>>
>> hs24 webrev: http://cr.openjdk.java.net/~jiangli/8001341/webrev_hs24.00/
>> jdk8 webrev: http://cr.openjdk.java.net/~jiangli/8001341/webrev_jdk8.00/
>>
>> The SIGSEGV was caused by an unhandled methodOop in methodOopDesc::fast_exception_handler_bci_for() and JvmtiExport::post_exception_throw(). It's only reproducible on hs24 as oops in the perm-gen could be moved by the GC. The bug was not reported on jdk8. On jdk8, Method* doesn't move. However the fix is still needed on jdk8 since the Method* in JvmtiExport::post_exception_throw() could be redefined after the  methodOopDesc::fast_exception_handler_bci_for() call. The handle will keep it from being deallocated.
> I was just going to say it's not required for HS25 but the redefinition is a valid point.  Although imperceptible.  Could we add a comment in:
>
> src/share/vm/oops/method.hpp
>
> to prevent someone undoing this change?
>
> -- Chris
>
>> Tested with -XX:+CheckUnhandledOops on solaris (x64) using vm.quick.testlist. Tested with jprt.
>>
>> Thanks,
>> Jiangli