[PATCH 1/2] KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler

From: Oliver Upton
Date: Mon May 09 2022 - 12:26:25 EST


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@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/nvhe/switch.c | 19 +------------------
1 file changed, 1 insertion(+), 18 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 6410d21d8695..3dee2ad96e10 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/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,
--
2.36.0.512.ge40c2bad7a-goog