Re: [PATCH v4] arm64: Change type of hsr, cpsr, spsr_el1 to uint64_t

[Julien Grall <julien@xen.org>]

Hi Michal,

On 05/07/2021 07:39, Michal Orzel wrote:
> AArch64 registers are 64bit whereas AArch32 registers
> are 32bit or 64bit. MSR/MRS are expecting 64bit values thus
> we should get rid of helpers READ/WRITE_SYSREG32
> in favour of using READ/WRITE_SYSREG.
> We should also use register_t type when reading sysregs
> which can correspond to uint64_t or uint32_t.
> Even though many AArch64 registers have upper 32bit reserved
> it does not mean that they can't be widen in the future.
> 
> Modify type of hsr, cpsr, spsr_el1 to uint64_t.
> Previously we relied on the padding after spsr_el1.
> As we removed the padding, modify the union to be 64bit so we don't corrupt spsr_fiq.
> No need to modify the assembly code because the accesses were based on 64bit
> registers as there was a 32bit padding after spsr_el1.
> 
> Remove 32bit padding in cpu_user_regs before spsr_fiq
> as it is no longer needed due to upper union being 64bit now.
> Add 64bit padding in cpu_user_regs before spsr_el1
> because the kernel frame should be 16-byte aligned.
> 
> Change type of cpsr to uint64_t in the public outside interface
> "public/arch-arm.h" to allow ABI compatibility between 32bit and 64bit.
> Increment XEN_DOMCTL_INTERFACE_VERSION.
> 
> Change type of cpsr to uint64_t in the public outside interface
> "public/vm_event.h" to allow ABI compatibility between 32bit and 64bit.
> 
> Signed-off-by: Michal Orzel <michal.orzel@arm.com>

Reviewed-by: Julien Grall <jgrall@amazon.com>

and committed.

Cheers,

-- 
Julien Grall