[PATCH v1 0/3] arm64/sve: Document our actual SVE syscall ABI

[Catalin Marinas]

On Wed, Jul 20, 2022 at 09:50:10PM +0100, Mark Brown wrote:
> Currently our SVE syscall ABI documentation does not reflect the actual
> implemented ABI, it says that register state not shared with FPSIMD
> becomes undefined on syscall when in reality we always clear it. Since
> changing this would cause a change in the observed kernel behaviour
> there is a substantial desire to avoid taking advantage of the
> documented ABI so instead let's document what we actually do so it's
> clear that it is in reality an ABI.
> 
> There has been some pushback on tightening the documentation in the past
> but it is hard to see who that helps, it makes the implementation
> decisions less clear and makes it harder for people to discover and make
> use of the actual ABI. The main practical concern is that qemu's user
> mode does not currently flush the registers.
> 
> Mark Brown (3):
>   kselftest/arm64: Correct buffer allocation for SVE Z registers
>   arm64/sve: Document our actual ABI for clearing registers on syscall
>   kselftest/arm64: Enforce actual ABI for SVE syscalls

For the series:

Acked-by: Catalin Marinas <catalin.marinas at arm.com>