[Valgrind-users] Marking blocks as write-once/grow-only

[Alex B. <ker...@be...>]

Hi,

I was recently using Valgrind to investigate some issues with QEMU's
multi-threading behaviour. One problem was without locking the code
generator multiple threads started accessing the codegen buffer and
hilarity ensued.

Is it possible for the DRD/Helgrind tools to detect this sort of
double-write access behaviour? Could I instrument QEMU so it marked the
codegen buffer as one that should only grow upwards (modulo-patchable
bits) so if anything re-wrote the buffer it could trigger an error?

-- 
Alex Bennée