RFR(XS) 8160411: SIGSEGV in frame::safe_for_sender on incomplete DeoptimizationBlob frame

[Andrew Haley]

On 20/10/16 23:47, dean.long at oracle.com wrote:
> https://bugs.openjdk.java.net/browse/JDK-8160411
> 
> http://cr.openjdk.java.net/~dlong/8160411/webrev/
> 
> I have only observed this crash on solaris x64 so far, but I have 
> included aarch64 in the fix since it uses similar code to x64. This 
> crash happens when we call pd_get_top_frame_for_profiling() and the top 
> frame is executing in the deopt stub, but hasn't finished pushing all 
> the registers yet.  If we add cb->frame_size() at this point, we can end 
> up with a sender_sp that is past the stack base.  The fix is to add a 
> range check for sender_sp before using it.
> 
> Tested by hand on linux x64 by forcing a SEGV in the deopt stub, then 
> calling pd_get_top_frame_for_profiling() and safe_for_sender() in the 
> signal handler.

That looks good.

Thanks,

Andrew.