Commit b877e984 authored by David Brazdil's avatar David Brazdil Committed by Marc Zyngier
Browse files

KVM: arm64: Build hyp-entry.S separately for VHE/nVHE 



hyp-entry.S contains implementation of KVM hyp vectors. This code is mostly
shared between VHE/nVHE, therefore compile it under both VHE and nVHE build
rules. nVHE-specific host HVC handler is hidden behind __KVM_NVHE_HYPERVISOR__.

Adjust code which selects which KVM hyp vecs to install to choose the correct
VHE/nVHE symbol.

Signed-off-by: default avatarDavid Brazdil <dbrazdil@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-7-dbrazdil@google.com
parent f50b6f6a

arch/arm64/include/asm/kvm_asm.h

+17 −5
Original line number Diff line number Diff line
@@ -60,12 +60,17 @@ 
	DECLARE_KVM_VHE_SYM(sym);		\

	DECLARE_KVM_NVHE_SYM(sym)



/* Translate a kernel address of @sym into its equivalent linear mapping */

#define kvm_ksym_ref(sym)						\

#define CHOOSE_VHE_SYM(sym)	sym

#define CHOOSE_NVHE_SYM(sym)	kvm_nvhe_sym(sym)

#define CHOOSE_HYP_SYM(sym)	(has_vhe() ? CHOOSE_VHE_SYM(sym) \

					   : CHOOSE_NVHE_SYM(sym))



/* Translate a kernel address @ptr into its equivalent linear mapping */

#define kvm_ksym_ref(ptr)						\

	({								\

		void *val = &sym;					\

		void *val = (ptr);					\

		if (!is_kernel_in_hyp_mode())				\

			val = lm_alias(&sym);				\

			val = lm_alias((ptr));				\

		val;							\

	 })

#define kvm_ksym_ref_nvhe(sym)	kvm_ksym_ref(kvm_nvhe_sym(sym))
@@ -76,7 +81,14 @@ struct kvm_vcpu; 
extern char __kvm_hyp_init[];

extern char __kvm_hyp_init_end[];



extern char __kvm_hyp_vector[];

DECLARE_KVM_HYP_SYM(__kvm_hyp_vector);

#define __kvm_hyp_vector	CHOOSE_HYP_SYM(__kvm_hyp_vector)



#ifdef CONFIG_KVM_INDIRECT_VECTORS

extern atomic_t arm64_el2_vector_last_slot;

DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs);

#define __bp_harden_hyp_vecs	CHOOSE_HYP_SYM(__bp_harden_hyp_vecs)

#endif



extern void __kvm_flush_vm_context(void);

extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);

arch/arm64/include/asm/mmu.h

+0 −7
Original line number Diff line number Diff line
@@ -45,13 +45,6 @@ struct bp_hardening_data { 
	bp_hardening_cb_t	fn;

};



#if (defined(CONFIG_HARDEN_BRANCH_PREDICTOR) ||	\

     defined(CONFIG_HARDEN_EL2_VECTORS))



extern char __bp_harden_hyp_vecs[];

extern atomic_t arm64_el2_vector_last_slot;

#endif  /* CONFIG_HARDEN_BRANCH_PREDICTOR || CONFIG_HARDEN_EL2_VECTORS */



#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR

DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);

arch/arm64/kernel/image-vars.h

+24 −0
Original line number Diff line number Diff line
@@ -66,8 +66,17 @@ __efistub__ctype = _ctype; 
/* Symbols defined in debug-sr.c (not yet compiled with nVHE build rules). */

KVM_NVHE_ALIAS(__kvm_get_mdcr_el2);



/* Symbols defined in entry.S (not yet compiled with nVHE build rules). */

KVM_NVHE_ALIAS(__guest_exit);

KVM_NVHE_ALIAS(abort_guest_exit_end);

KVM_NVHE_ALIAS(abort_guest_exit_start);



/* Symbols defined in hyp-init.S (not yet compiled with nVHE build rules). */

KVM_NVHE_ALIAS(__kvm_handle_stub_hvc);



/* Symbols defined in switch.c (not yet compiled with nVHE build rules). */

KVM_NVHE_ALIAS(__kvm_vcpu_run_nvhe);

KVM_NVHE_ALIAS(hyp_panic);



/* Symbols defined in sysreg-sr.c (not yet compiled with nVHE build rules). */

KVM_NVHE_ALIAS(__kvm_enable_ssbs);
@@ -89,6 +98,21 @@ KVM_NVHE_ALIAS(__vgic_v3_restore_aprs); 
KVM_NVHE_ALIAS(__vgic_v3_save_aprs);

KVM_NVHE_ALIAS(__vgic_v3_write_vmcr);



/* Alternative callbacks for init-time patching of nVHE hyp code. */

KVM_NVHE_ALIAS(arm64_enable_wa2_handling);

KVM_NVHE_ALIAS(kvm_patch_vector_branch);

KVM_NVHE_ALIAS(kvm_update_va_mask);



/* Global kernel state accessed by nVHE hyp code. */

KVM_NVHE_ALIAS(arm64_ssbd_callback_required);

KVM_NVHE_ALIAS(kvm_host_data);



/* Kernel constant needed to compute idmap addresses. */

KVM_NVHE_ALIAS(kimage_voffset);



/* Kernel symbols used to call panic() from nVHE hyp code (via ERET). */

KVM_NVHE_ALIAS(panic);



#endif /* CONFIG_KVM */



#endif /* __ARM64_KERNEL_IMAGE_VARS_H */

arch/arm64/kvm/arm.c

+1 −1
Original line number Diff line number Diff line
@@ -1285,7 +1285,7 @@ static void cpu_init_hyp_mode(void) 
	 * so that we can use adr_l to access per-cpu variables in EL2.

	 */

	tpidr_el2 = ((unsigned long)this_cpu_ptr(&kvm_host_data) -

		     (unsigned long)kvm_ksym_ref(kvm_host_data));

		     (unsigned long)kvm_ksym_ref(&kvm_host_data));



	pgd_ptr = kvm_mmu_get_httbr();

	hyp_stack_ptr = __this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE;

arch/arm64/kvm/hyp/Makefile

+2 −2
Original line number Diff line number Diff line
@@ -10,11 +10,11 @@ subdir-ccflags-y := -I$(incdir) \ 
		    -DDISABLE_BRANCH_PROFILING		\

		    $(DISABLE_STACKLEAK_PLUGIN)



obj-$(CONFIG_KVM) += hyp.o nvhe/

obj-$(CONFIG_KVM) += hyp.o vhe/ nvhe/

obj-$(CONFIG_KVM_INDIRECT_VECTORS) += smccc_wa.o



hyp-y := vgic-v3-sr.o timer-sr.o aarch32.o vgic-v2-cpuif-proxy.o sysreg-sr.o \

	 debug-sr.o entry.o switch.o fpsimd.o tlb.o hyp-entry.o

	 debug-sr.o entry.o switch.o fpsimd.o tlb.o



# KVM code is run at a different exception code with a different map, so

# compiler instrumentation that inserts callbacks or checks into the code may

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