KVM: arm64: Simplify warning in kvm_arch_vcpu_load_fp()

At the end of kvm_arch_vcpu_load_fp() we check that no bits are set in
SVCR. We only check this for protected mode despite this mattering
equally for non-protected mode, and the comment above this is confusing.

Remove the comment and simplify the check, moving from WARN_ON() to
WARN_ON_ONCE() to avoid spamming the log.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c
index 3cbb999419af7bb31ce9cec2baafcad00491610a..7f6e43d256915f507061c7c0fefd5b24febd6043 100644 (file)
--- a/arch/arm64/kvm/fpsimd.c
+++ b/arch/arm64/kvm/fpsimd.c
@@ -65,12 +65,7 @@ void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu)
        fpsimd_save_and_flush_cpu_state();
        *host_data_ptr(fp_owner) = FP_STATE_FREE;
 
-       /*
-        * If normal guests gain SME support, maintain this behavior for pKVM
-        * guests, which don't support SME.
-        */
-       WARN_ON(is_protected_kvm_enabled() && system_supports_sme() &&
-               read_sysreg_s(SYS_SVCR));
+       WARN_ON_ONCE(system_supports_sme() && read_sysreg_s(SYS_SVCR));
 }
 
 /*