[PATCH] D16689: [tsan] Dynamically detect heap range for aarch64.

[Dmitry Vyukov via llvm-commits]

dvyukov added a comment.

> There will be a Linaro Connect in two weeks, and I'll bring that up with the kernel folks this topic, as well as try to reduce the already almost useless slow down.


It would be great if kernel provided a "sanitizer-friendly" mapping.

FWIW, some time ago we had support for so called "COMPAT" mapping for x86. In that mode kernel mapped modules around 0x2a0000000000. The shadow mapping for that mode was not a bijection, instead it was a injection. Several user regions mapped onto the same shadow, but during runtime only one of the user regions was occupied so no clashes happened. This allowed us to support huge user memory range (like in this case) and map it onto smaller shadow. The problem was with the reverse mapping, though (e.g. when we print racy address in report). You can find that code in history.


http://reviews.llvm.org/D16689