Feature request for enabling SCTLR_ELx.nAA

[Richard Henderson]

On 2/23/23 02:15, Catalin Marinas wrote:
> Given that allowing unaligned accesses could break atomicity, I wouldn't
> set this bit to 1 permanently, it helps catching tricky software bugs.
> So a prctl() makes more sense. If your intended use is just preserving
> the acquire/release semantics, I don't think these are affected by the
> atomicity rules even if they go across a 16-byte boundary.

Yes, my intended use is just the acquire/release.

As I read the Arm ARM pseudo-code for aarch64/functions/memory/Mem, the !aligned case 
devolves to a series of bytes, but with the same acctype, so each byte is AccType_ORDERED.

Which is just fine for my use case.


r~