Re: [PATCH 3/3] KVM: arm64: nv: Handle all _EL02 and _EL12 registers

[Marc Zyngier]

On Wed, 13 Sep 2023 19:52:08 +0100,
Miguel Luis <miguel.luis@xxxxxxxxxx> wrote:
> 
> Specify both _EL02 and _EL12 system registers.
> 
> Signed-off-by: Miguel Luis <miguel.luis@xxxxxxxxxx>
> ---
>  arch/arm64/kvm/emulate-nested.c | 35 +++++++++++++++++++++++++++++----
>  1 file changed, 31 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c
> index 9aa1c06abdb7..957afd97e488 100644
> --- a/arch/arm64/kvm/emulate-nested.c
> +++ b/arch/arm64/kvm/emulate-nested.c
> @@ -690,10 +690,37 @@ static const struct encoding_to_trap_config encoding_to_cgt[] __initconst = {
>  	SR_RANGE_TRAP(sys_reg(3, 4, 14, 0, 3),
>  			sys_reg(3, 4, 14, 5, 2), CGT_HCR_NV),
>  	/* All _EL02, _EL12 registers */
> -	SR_RANGE_TRAP(sys_reg(3, 5, 0, 0, 0),
> -		      sys_reg(3, 5, 10, 15, 7), CGT_HCR_NV),
> -	SR_RANGE_TRAP(sys_reg(3, 5, 12, 0, 0),
> -		      sys_reg(3, 5, 14, 15, 7), CGT_HCR_NV),
> +	SR_TRAP(SYS_SCTLR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_CPACR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_SCTLR2_EL12,	CGT_HCR_NV),
> +	SR_TRAP(SYS_ZCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TRFCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_SMCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TTBR0_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TTBR1_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TCR2_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_SPSR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_ELR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_AFSR0_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_AFSR1_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_ESR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_TFSR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_FAR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_BRBCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_PMSCR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_MAIR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_AMAIR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_VBAR_EL12,		CGT_HCR_NV),
> +	SR_TRAP(SYS_CONTEXTIDR_EL12,	CGT_HCR_NV),
> +	SR_TRAP(SYS_SCXTNUM_EL12,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTKCTL_EL12,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTP_TVAL_EL02,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTP_CTL_EL02,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTP_CVAL_EL02,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTV_TVAL_EL02,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTV_CTL_EL02,	CGT_HCR_NV),
> +	SR_TRAP(SYS_CNTV_CVAL_EL02,	CGT_HCR_NV),
>  	SR_TRAP(OP_AT_S1E2R,		CGT_HCR_NV),
>  	SR_TRAP(OP_AT_S1E2W,		CGT_HCR_NV),
>  	SR_TRAP(OP_AT_S12E1R,		CGT_HCR_NV),

While I could see the problem with the EL2 registers, I'm not
convinced by this patch. Is there an actual case for non _EL02, non
_EL12 registers that are included in the two ranges above?

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.