Re: [RFC PATCH 02/27] KVM: arm64: Link position-independent string routines into .hyp.text

[David Brazdil]

On Tue, Nov 17, 2020 at 06:15:42PM +0000, 'Quentin Perret' via kernel-team wrote:
> From: Will Deacon <will@xxxxxxxxxx>
> 
> Pull clear_page(), copy_page(), memcpy() and memset() into the nVHE hyp
> code and ensure that we always execute the '__pi_' entry point on the
> offchance that it changes in future.
> 
> [ qperret: Commit title nits ]
> 
> Signed-off-by: Will Deacon <will@xxxxxxxxxx>
> Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
> ---
>  arch/arm64/kernel/image-vars.h   | 11 +++++++++++
>  arch/arm64/kvm/hyp/nvhe/Makefile |  4 ++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
> index 8539f34d7538..dd8ccc9efb6a 100644
> --- a/arch/arm64/kernel/image-vars.h
> +++ b/arch/arm64/kernel/image-vars.h
> @@ -105,6 +105,17 @@ KVM_NVHE_ALIAS(__stop___kvm_ex_table);
>  /* Array containing bases of nVHE per-CPU memory regions. */
>  KVM_NVHE_ALIAS(kvm_arm_hyp_percpu_base);
>  
> +/* Position-independent library routines */
> +__kvm_nvhe_clear_page			= __kvm_nvhe___pi_clear_page;
> +__kvm_nvhe_copy_page			= __kvm_nvhe___pi_copy_page;
> +__kvm_nvhe_memcpy			= __kvm_nvhe___pi_memcpy;
> +__kvm_nvhe_memset			= __kvm_nvhe___pi_memset;
> +
> +#ifdef CONFIG_KASAN
> +__kvm_nvhe___memcpy			= __kvm_nvhe___pi_memcpy;
> +__kvm_nvhe___memset			= __kvm_nvhe___pi_memset;
> +#endif
> +
>  #endif /* CONFIG_KVM */

Nit: Would be good to use the kvm_nvhe_sym() helper for the namespacing.
And feel free to define something like KVM_NVHE_ALIAS for PI in hyp-image.h.

>  
>  #endif /* __ARM64_KERNEL_IMAGE_VARS_H */
> diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
> index 1f1e351c5fe2..590fdefb42dd 100644
> --- a/arch/arm64/kvm/hyp/nvhe/Makefile
> +++ b/arch/arm64/kvm/hyp/nvhe/Makefile
> @@ -6,10 +6,14 @@
>  asflags-y := -D__KVM_NVHE_HYPERVISOR__
>  ccflags-y := -D__KVM_NVHE_HYPERVISOR__
>  
> +lib-objs := clear_page.o copy_page.o memcpy.o memset.o
> +lib-objs := $(addprefix ../../../lib/, $(lib-objs))
> +
>  obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
>  	 hyp-main.o hyp-smp.o psci-relay.o
>  obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
>  	 ../fpsimd.o ../hyp-entry.o ../exception.o
> +obj-y += $(lib-objs)
>  
>  ##
>  ## Build rules for compiling nVHE hyp code
> -- 
> 2.29.2.299.gdc1121823c-goog
> 
> -- 
> To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@xxxxxxxxxxx.
>