Re: [PATCH 02/26] KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h

Suzuki K Poulose
2020-04-22T13:46:22Z

Hi Marc,

On 04/22/2020 01:00 PM, Marc Zyngier wrote:
> Having __load_guest_stage2 in kvm_hyp.h is quickly going to trigger
> a circular include problem. In order to avoid this, let's move
> it to kvm_mmu.h, where it will be a better fit anyway.
>
> In the process, drop the __hyp_text annotation, which doesn't help
> as the function is marked as __always_inline.
>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

> ---
> arch/arm64/include/asm/kvm_hyp.h | 18 ------------------
> arch/arm64/include/asm/kvm_mmu.h | 17 +++++++++++++++++
> 2 files changed, 17 insertions(+), 18 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
> index fe57f60f06a89..dcb63bf941057 100644
> --- a/arch/arm64/include/asm/kvm_hyp.h
> +++ b/arch/arm64/include/asm/kvm_hyp.h
> @@ -10,7 +10,6 @@
> #include <linux/compiler.h>
> #include <linux/kvm_host.h>
> #include <asm/alternative.h>
> -#include <asm/kvm_mmu.h>
> #include <asm/sysreg.h>
>
> #define __hyp_text __section(.hyp.text) notrace
> @@ -88,22 +87,5 @@ void deactivate_traps_vhe_put(void);
> u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
> void __noreturn __hyp_do_panic(unsigned long, ...);
>
> -/*
> - * Must be called from hyp code running at EL2 with an updated VTTBR
> - * and interrupts disabled.
> - */
> -static __always_inline void __hyp_text __load_guest_stage2(struct kvm *kvm)
> -{
> - write_sysreg(kvm->arch.vtcr, vtcr_el2);
> - write_sysreg(kvm_get_vttbr(kvm), vttbr_el2);
> -
> - /*
> - * ARM errata 1165522 and 1530923 require the actual execution of the
> - * above before we can switch to the EL1/EL0 translation regime used by
> - * the guest.
> - */
> - asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT_VHE));
> -}
> -
> #endif /* __ARM64_KVM_HYP_H__ */
>
> diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
> index 30b0e8d6b8953..5ba1310639ec6 100644
> --- a/arch/arm64/include/asm/kvm_mmu.h
> +++ b/arch/arm64/include/asm/kvm_mmu.h
> @@ -604,5 +604,22 @@ static __always_inline u64 kvm_get_vttbr(struct kvm *kvm)
> return kvm_phys_to_vttbr(baddr) | vmid_field | cnp;
> }
>
> +/*
> + * Must be called from hyp code running at EL2 with an updated VTTBR
> + * and interrupts disabled.
> + */
> +static __always_inline void __load_guest_stage2(struct kvm *kvm)
> +{
> + write_sysreg(kvm->arch.vtcr, vtcr_el2);
> + write_sysreg(kvm_get_vttbr(kvm), vttbr_el2);
> +
> + /*
> + * ARM erratum 1165522 requires the actual execution of the above

Is it intentional to drop the reference to errata 1530923 ?

Otherwise :

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>