KVM: arm64: Remove __pkvm_mark_hyp

Now that we mark memory owned by the hypervisor in the host stage-2
during __pkvm_init(), we no longer need to rely on the host to
explicitly mark the hyp sections later on.

Remove the __pkvm_mark_hyp() hypercall altogether.
Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-19-qperret@google.com

arch/arm64/include/asm/kvm_asm.h

@@ -63,8 +63,7 @@
 #define __KVM_HOST_SMCCC_FUNC___pkvm_create_private_mapping	17
 #define __KVM_HOST_SMCCC_FUNC___pkvm_cpu_set_vector		18
 #define __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize		19
-#define __KVM_HOST_SMCCC_FUNC___pkvm_mark_hyp			20
-#define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc			21
+#define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc			20
 
 #ifndef __ASSEMBLY__
 

arch/arm64/kvm/arm.c

@@ -1954,57 +1954,11 @@ static void _kvm_host_prot_finalize(void *discard)
 	WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize));
 }
 
-static inline int pkvm_mark_hyp(phys_addr_t start, phys_addr_t end)
-{
-	return kvm_call_hyp_nvhe(__pkvm_mark_hyp, start, end);
-}
-
-#define pkvm_mark_hyp_section(__section)		\
-	pkvm_mark_hyp(__pa_symbol(__section##_start),	\
-			__pa_symbol(__section##_end))
-
 static int finalize_hyp_mode(void)
 {
-	int cpu, ret;
-
 	if (!is_protected_kvm_enabled())
 		return 0;
 
-	ret = pkvm_mark_hyp_section(__hyp_idmap_text);
-	if (ret)
-		return ret;
-
-	ret = pkvm_mark_hyp_section(__hyp_text);
-	if (ret)
-		return ret;
-
-	ret = pkvm_mark_hyp_section(__hyp_rodata);
-	if (ret)
-		return ret;
-
-	ret = pkvm_mark_hyp_section(__hyp_bss);
-	if (ret)
-		return ret;
-
-	ret = pkvm_mark_hyp(hyp_mem_base, hyp_mem_base + hyp_mem_size);
-	if (ret)
-		return ret;
-
-	for_each_possible_cpu(cpu) {
-		phys_addr_t start = virt_to_phys((void *)kvm_arm_hyp_percpu_base[cpu]);
-		phys_addr_t end = start + (PAGE_SIZE << nvhe_percpu_order());
-
-		ret = pkvm_mark_hyp(start, end);
-		if (ret)
-			return ret;
-
-		start = virt_to_phys((void *)per_cpu(kvm_arm_hyp_stack_page, cpu));
-		end = start + PAGE_SIZE;
-		ret = pkvm_mark_hyp(start, end);
-		if (ret)
-			return ret;
-	}
-
 	/*
 	 * Flip the static key upfront as that may no longer be possible
 	 * once the host stage 2 is installed.

arch/arm64/kvm/hyp/include/nvhe/mem_protect.h

@@ -49,7 +49,6 @@ extern struct host_kvm host_kvm;
 extern const u8 pkvm_hyp_id;
 
 int __pkvm_prot_finalize(void);
-int __pkvm_mark_hyp(phys_addr_t start, phys_addr_t end);
 
 bool addr_is_memory(phys_addr_t phys);
 int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_prot prot);

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

@@ -163,14 +163,6 @@ static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
 {
 	cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
 }
-
-static void handle___pkvm_mark_hyp(struct kvm_cpu_context *host_ctxt)
-{
-	DECLARE_REG(phys_addr_t, start, host_ctxt, 1);
-	DECLARE_REG(phys_addr_t, end, host_ctxt, 2);
-
-	cpu_reg(host_ctxt, 1) = __pkvm_mark_hyp(start, end);
-}
 typedef void (*hcall_t)(struct kvm_cpu_context *);
 
 #define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
@@ -196,7 +188,6 @@ static const hcall_t host_hcall[] = {
 	HANDLE_FUNC(__pkvm_create_mappings),
 	HANDLE_FUNC(__pkvm_create_private_mapping),
 	HANDLE_FUNC(__pkvm_prot_finalize),
-	HANDLE_FUNC(__pkvm_mark_hyp),
 };
 
 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)

arch/arm64/kvm/hyp/nvhe/mem_protect.c

@@ -339,25 +339,6 @@ static int host_stage2_idmap(u64 addr)
 	return ret;
 }
 
-int __pkvm_mark_hyp(phys_addr_t start, phys_addr_t end)
-{
-	int ret;
-
-	/*
-	 * host_stage2_unmap_dev_all() currently relies on MMIO mappings being
-	 * non-persistent, so don't allow changing page ownership in MMIO range.
-	 */
-	if (!range_is_memory(start, end))
-		return -EINVAL;
-
-	hyp_spin_lock(&host_kvm.lock);
-	ret = host_stage2_try(kvm_pgtable_stage2_set_owner, &host_kvm.pgt,
-			      start, end - start, &host_s2_pool, pkvm_hyp_id);
-	hyp_spin_unlock(&host_kvm.lock);
-
-	return ret != -EAGAIN ? ret : 0;
-}
-
 void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt)
 {
 	struct kvm_vcpu_fault_info fault;