Re: [PATCH v4 23/27] KVM: s390: arm64: Implement required functions

[Janosch Frank]

On 7/6/26 10:52, Steffen Eiden wrote:
> Implement the mostly trivial functions that the shared arm64 (kvm)
> code & headers oblige s390 to implement.
>
> Implement a very basic smccc handler that (non-compliantly) is just able
> to stop a vcpu.
>
> Signed-off-by: Steffen Eiden <seiden@xxxxxxxxxxxxx>
> ---
>   arch/s390/include/arm64/kvm_emulate.h | 135 ++++++++++++++++++++++++++
>   arch/s390/include/arm64/kvm_nested.h  |  11 +++
>   arch/s390/kvm/arm64/handle_exit.c     | 110 +++++++++++++++++++++
>   arch/s390/kvm/arm64/inject_fault.c    |  21 ++++
>   4 files changed, 277 insertions(+)
>   create mode 100644 arch/s390/include/arm64/kvm_emulate.h
>   create mode 100644 arch/s390/include/arm64/kvm_nested.h
>   create mode 100644 arch/s390/kvm/arm64/handle_exit.c
>   create mode 100644 arch/s390/kvm/arm64/inject_fault.c

[...]

> +/* manually copied from arch/arm64/kernel/traps.c */
> +static const char * const esr_class_str[] = {
> +	[0 ... ESR_ELx_EC_MAX]		= "UNRECOGNIZED EC",
> +	[ESR_ELx_EC_UNKNOWN]		= "Unknown/Uncategorized",
> +	[ESR_ELx_EC_WFx]		= "WFI/WFE",
> +	[ESR_ELx_EC_CP15_32]		= "CP15 MCR/MRC",
> +	[ESR_ELx_EC_CP15_64]		= "CP15 MCRR/MRRC",
> +	[ESR_ELx_EC_CP14_MR]		= "CP14 MCR/MRC",
> +	[ESR_ELx_EC_CP14_LS]		= "CP14 LDC/STC",
> +	[ESR_ELx_EC_FP_ASIMD]		= "ASIMD",
> +	[ESR_ELx_EC_CP10_ID]		= "CP10 MRC/VMRS",
> +	[ESR_ELx_EC_PAC]		= "PAC",
> +	[ESR_ELx_EC_CP14_64]		= "CP14 MCRR/MRRC",
> +	[ESR_ELx_EC_BTI]		= "BTI",
> +	[ESR_ELx_EC_ILL]		= "PSTATE.IL",
> +	[ESR_ELx_EC_SVC32]		= "SVC (AArch32)",
> +	[ESR_ELx_EC_HVC32]		= "HVC (AArch32)",
> +	[ESR_ELx_EC_SMC32]		= "SMC (AArch32)",
> +	[ESR_ELx_EC_SVC64]		= "SVC (AArch64)",
> +	[ESR_ELx_EC_HVC64]		= "HVC (AArch64)",
> +	[ESR_ELx_EC_SMC64]		= "SMC (AArch64)",
> +	[ESR_ELx_EC_SYS64]		= "MSR/MRS (AArch64)",
> +	[ESR_ELx_EC_SVE]		= "SVE",
> +	[ESR_ELx_EC_ERET]		= "ERET/ERETAA/ERETAB",
> +	[ESR_ELx_EC_FPAC]		= "FPAC",
> +	[ESR_ELx_EC_SME]		= "SME",
> +	[ESR_ELx_EC_IMP_DEF]		= "EL3 IMP DEF",
> +	[ESR_ELx_EC_IABT_LOW]		= "IABT (lower EL)",
> +	[ESR_ELx_EC_IABT_CUR]		= "IABT (current EL)",
> +	[ESR_ELx_EC_PC_ALIGN]		= "PC Alignment",
> +	[ESR_ELx_EC_DABT_LOW]		= "DABT (lower EL)",
> +	[ESR_ELx_EC_DABT_CUR]		= "DABT (current EL)",
> +	[ESR_ELx_EC_SP_ALIGN]		= "SP Alignment",
> +	[ESR_ELx_EC_MOPS]		= "MOPS",
> +	[ESR_ELx_EC_FP_EXC32]		= "FP (AArch32)",
> +	[ESR_ELx_EC_FP_EXC64]		= "FP (AArch64)",
> +	[ESR_ELx_EC_GCS]		= "Guarded Control Stack",
> +	[ESR_ELx_EC_SERROR]		= "SError",
> +	[ESR_ELx_EC_BREAKPT_LOW]	= "Breakpoint (lower EL)",
> +	[ESR_ELx_EC_BREAKPT_CUR]	= "Breakpoint (current EL)",
> +	[ESR_ELx_EC_SOFTSTP_LOW]	= "Software Step (lower EL)",
> +	[ESR_ELx_EC_SOFTSTP_CUR]	= "Software Step (current EL)",
> +	[ESR_ELx_EC_WATCHPT_LOW]	= "Watchpoint (lower EL)",
> +	[ESR_ELx_EC_WATCHPT_CUR]	= "Watchpoint (current EL)",
> +	[ESR_ELx_EC_BKPT32]		= "BKPT (AArch32)",
> +	[ESR_ELx_EC_VECTOR32]		= "Vector catch (AArch32)",
> +	[ESR_ELx_EC_BRK64]		= "BRK (AArch64)",
> +};
> +
We could rip out the 32bit ones.
Not necessarily right now as it's easier to compare to the aarch64 
implementation like this but at least at a later time.

I was also wondering if it would make sense to have all the feature 
checks for unimplemented features in one file.