Re: [Qemu-arm] [PATCH 05/13] target/arm/kvm: Add kvm_arch_get/put_sve

[Dave Martin]

On Sun, May 12, 2019 at 09:36:16AM +0100, Andrew Jones wrote:
> These are the SVE equivalents to kvm_arch_get/put_fpsimd.
> 
> Signed-off-by: Andrew Jones <address@hidden>
> ---
>  target/arm/kvm64.c | 127 +++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 123 insertions(+), 4 deletions(-)

[...]

> +static int kvm_arch_put_sve(CPUState *cs)
> +{
> +    ARMCPU *cpu = ARM_CPU(cs);
> +    CPUARMState *env = &cpu->env;
> +    struct kvm_one_reg reg;
> +    int n, ret;
> +
> +    for (n = 0; n < KVM_ARM64_SVE_NUM_ZREGS; n++) {
> +        uint64_t *q = aa64_vfp_qreg(env, n);
> +#ifdef HOST_WORDS_BIGENDIAN
> +        uint64_t d[ARM_MAX_VQ * 2];
> +        int i;
> +        for (i = 0; i < cpu->sve_max_vq * 2; i++) {
> +            d[i] = q[cpu->sve_max_vq * 2 - 1 - i];
> +        }
> +        reg.addr = (uintptr_t)d;
> +#else
> +        reg.addr = (uintptr_t)q;
> +#endif
> +        reg.id = KVM_REG_ARM64_SVE_ZREG(n, 0);

Will this silently go wrong if more than one slice is required (i.e.,
the register size grows beyond 8192 bits?)

[...]

Cheers
---Dave