Hi That indeed a good idea. Thank you guys. 2015-02-17 19:52 GMT+01:00 Matthew LeGendre <[email protected]>:
> > On Tue, 17 Feb 2015, Bill Williams wrote: > >> On 02/17/2015 07:05 AM, Xi Chen wrote: >> >>> Hi, >>> I recently try to debug the dynamic mode dyninst because I found the >>> result is inconsistent with the static rewrite. I basically want to >>> attach to mutatee process, and see how the instrumentation code be >>> executed. However, when I do that in GDB, it tell me the ptrace >>> operation is not permitted (I have teh yama/ptrace_scope as 0). I wonder >>> if there are any way I can attach to the mutatee's address space and >>> debug there? >>> >> >> Not without detaching your mutator first; ptrace only allows one debugger >> at a time to be attached. >> >> You can, however, use breakpoint snippets and the stack walking interface >> in BPatch_process for programmatic debugging. You can also enable >> DYNINST_DEBUG_RELOC and/or DYNINST_DEBUG_SPRINGBOARD in your environment to >> see what, exactly, we're generating for relocated/instrumented code and for >> branches that lead to it, respectively. >> > > Core files can also be a convenient way to debug generated > instrumentation. Just send the process a SIGSEGV after instrumenting. You > can't walk through the code as it runs, but with gdb's 'disass' command you > can dump the assembly showing what was generated and modified. > > -Matt > -- Best Regards X.Chen
_______________________________________________ Dyninst-api mailing list [email protected] https://lists.cs.wisc.edu/mailman/listinfo/dyninst-api
