On Fri, Mar 9, 2018 at 3:15 PM, Robin Murphy <robin.murphy@xxxxxxx> wrote: > Hi Andrey, > > On 09/03/18 14:01, Andrey Konovalov wrote: >> >> arm64 has a feature called Top Byte Ignore, which allows to embed pointer >> tags into the top byte of each pointer. Userspace programs (such as >> HWASan, a memory debugging tool [1]) might use this feature and pass >> tagged user pointers to the kernel through syscalls or other interfaces. > > > If you propose changing the ABI, then > Documentation/arm64/tagged-pointers.txt needs to reflect the new one, since > passing nonzero tags via syscalls is currently explicitly forbidden. > > Robin. Hi Robin! I will include changes to Documentation/arm64/tagged-pointers.txt in the next version. Thanks!
