Commit 537db4af authored by David Brazdil's avatar David Brazdil Committed by Marc Zyngier
Browse files

KVM: arm64: Remove patching of fn pointers in hyp 



Storing a function pointer in hyp now generates relocation information
used at early boot to convert the address to hyp VA. The existing
alternative-based conversion mechanism is therefore obsolete. Remove it
and simplify its users.

Acked-by: default avatarArd Biesheuvel <ardb@kernel.org>
Signed-off-by: default avatarDavid Brazdil <dbrazdil@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210105180541.65031-8-dbrazdil@google.com
parent 97cbd2fc

arch/arm64/include/asm/kvm_mmu.h

+0 −18
Original line number Diff line number Diff line
@@ -135,24 +135,6 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v) 


#define kern_hyp_va(v) 	((typeof(v))(__kern_hyp_va((unsigned long)(v))))



static __always_inline unsigned long __kimg_hyp_va(unsigned long v)

{

	unsigned long offset;



	asm volatile(ALTERNATIVE_CB("movz %0, #0\n"

				    "movk %0, #0, lsl #16\n"

				    "movk %0, #0, lsl #32\n"

				    "movk %0, #0, lsl #48\n",

				    kvm_update_kimg_phys_offset)

		     : "=r" (offset));



	return __kern_hyp_va((v - offset) | PAGE_OFFSET);

}



#define kimg_fn_hyp_va(v) 	((typeof(*v))(__kimg_hyp_va((unsigned long)(v))))



#define kimg_fn_ptr(x)	(typeof(x) **)(x)



/*

 * We currently support using a VM-specified IPA size. For backward

 * compatibility, the default IPA size is fixed to 40bits.

arch/arm64/kernel/image-vars.h

+0 −1
Original line number Diff line number Diff line
@@ -64,7 +64,6 @@ __efistub__ctype = _ctype; 
/* Alternative callbacks for init-time patching of nVHE hyp code. */

KVM_NVHE_ALIAS(kvm_patch_vector_branch);

KVM_NVHE_ALIAS(kvm_update_va_mask);

KVM_NVHE_ALIAS(kvm_update_kimg_phys_offset);

KVM_NVHE_ALIAS(kvm_get_kimage_voffset);



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

arch/arm64/kvm/hyp/nvhe/hyp-main.c

+4 −7
Original line number Diff line number Diff line
@@ -108,9 +108,9 @@ static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt) 


typedef void (*hcall_t)(struct kvm_cpu_context *);



#define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = kimg_fn_ptr(handle_##x)

#define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x



static const hcall_t *host_hcall[] = {

static const hcall_t host_hcall[] = {

	HANDLE_FUNC(__kvm_vcpu_run),

	HANDLE_FUNC(__kvm_flush_vm_context),

	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
@@ -130,7 +130,6 @@ static const hcall_t *host_hcall[] = { 
static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)

{

	DECLARE_REG(unsigned long, id, host_ctxt, 0);

	const hcall_t *kfn;

	hcall_t hfn;



	id -= KVM_HOST_SMCCC_ID(0);
@@ -138,13 +137,11 @@ static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) 
	if (unlikely(id >= ARRAY_SIZE(host_hcall)))

		goto inval;



	kfn = host_hcall[id];

	if (unlikely(!kfn))

	hfn = host_hcall[id];

	if (unlikely(!hfn))

		goto inval;



	cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;



	hfn = kimg_fn_hyp_va(kfn);

	hfn(host_ctxt);



	return;

arch/arm64/kvm/va_layout.c

+0 −6
Original line number Diff line number Diff line
@@ -283,12 +283,6 @@ static void generate_mov_q(u64 val, __le32 *origptr, __le32 *updptr, int nr_inst 
	*updptr++ = cpu_to_le32(insn);

}



void kvm_update_kimg_phys_offset(struct alt_instr *alt,

				 __le32 *origptr, __le32 *updptr, int nr_inst)

{

	generate_mov_q(kimage_voffset + PHYS_OFFSET, origptr, updptr, nr_inst);

}



void kvm_get_kimage_voffset(struct alt_instr *alt,

			    __le32 *origptr, __le32 *updptr, int nr_inst)

{