KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler

The pVM-specific FP/SIMD trap handler just calls straight into the
generic trap handler. Avoid the indirection and just call the hyp
handler directly.

Note that the BUILD_BUG_ON() pattern is repeated in
pvm_init_traps_aa64pfr0(), which is likely a better home for it.

No functional change intended.
Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220509162559.2387784-2-oupton@google.com

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

@@ -175,23 +175,6 @@ static bool kvm_handle_pvm_sys64(struct kvm_vcpu *vcpu, u64 *exit_code)
 		kvm_handle_pvm_sysreg(vcpu, exit_code));
 }
 
-/*
- * Handler for protected floating-point and Advanced SIMD accesses.
- *
- * Returns true if the hypervisor has handled the exit, and control should go
- * back to the guest, or false if it hasn't.
- */
-static bool kvm_handle_pvm_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code)
-{
-	/* Linux guests assume support for floating-point and Advanced SIMD. */
-	BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_FP),
-				PVM_ID_AA64PFR0_ALLOW));
-	BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_ASIMD),
-				PVM_ID_AA64PFR0_ALLOW));
-
-	return kvm_hyp_handle_fpsimd(vcpu, exit_code);
-}
-
 static const exit_handler_fn hyp_exit_handlers[] = {
 	[0 ... ESR_ELx_EC_MAX]		= NULL,
 	[ESR_ELx_EC_CP15_32]		= kvm_hyp_handle_cp15_32,
@@ -207,7 +190,7 @@ static const exit_handler_fn pvm_exit_handlers[] = {
 	[0 ... ESR_ELx_EC_MAX]		= NULL,
 	[ESR_ELx_EC_SYS64]		= kvm_handle_pvm_sys64,
 	[ESR_ELx_EC_SVE]		= kvm_handle_pvm_restricted,
-	[ESR_ELx_EC_FP_ASIMD]		= kvm_handle_pvm_fpsimd,
+	[ESR_ELx_EC_FP_ASIMD]		= kvm_hyp_handle_fpsimd,
 	[ESR_ELx_EC_IABT_LOW]		= kvm_hyp_handle_iabt_low,
 	[ESR_ELx_EC_DABT_LOW]		= kvm_hyp_handle_dabt_low,
 	[ESR_ELx_EC_PAC]		= kvm_hyp_handle_ptrauth,