target/i386: kvm: do not use kvm_check_extension to find paravirtual capabilities

Paravirtualized features have been listed in KVM_GET_SUPPORTED_CPUID since
Linux 2.6.35 (commit 84478c829d0f, "KVM: x86: export paravirtual cpuid flags
in KVM_GET_SUPPORTED_CPUID", 2010-05-19).  It has been more than 10 years,
so remove the fallback code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 4fc6e8b9d54bd0661b7d4c07aaea64bfb8814ccd..f6dae4cfb6a9b183f5be5c9b6827ed35aa44daa8 100644 (file)
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -284,30 +284,6 @@ static struct kvm_cpuid2 *get_supported_cpuid(KVMState *s)
     return cpuid;
 }
 
-static const struct kvm_para_features {
-    int cap;
-    int feature;
-} para_features[] = {
-    { KVM_CAP_CLOCKSOURCE, KVM_FEATURE_CLOCKSOURCE },
-    { KVM_CAP_NOP_IO_DELAY, KVM_FEATURE_NOP_IO_DELAY },
-    { KVM_CAP_PV_MMU, KVM_FEATURE_MMU_OP },
-    { KVM_CAP_ASYNC_PF, KVM_FEATURE_ASYNC_PF },
-    { KVM_CAP_ASYNC_PF_INT, KVM_FEATURE_ASYNC_PF_INT },
-};
-
-static int get_para_features(KVMState *s)
-{
-    int i, features = 0;
-
-    for (i = 0; i < ARRAY_SIZE(para_features); i++) {
-        if (kvm_check_extension(s, para_features[i].cap)) {
-            features |= (1 << para_features[i].feature);
-        }
-    }
-
-    return features;
-}
-
 static bool host_tsx_broken(void)
 {
     int family, model, stepping;\
@@ -367,13 +343,11 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
     struct kvm_cpuid2 *cpuid;
     uint32_t ret = 0;
     uint32_t cpuid_1_edx;
-    bool found = false;
 
     cpuid = get_supported_cpuid(s);
 
     struct kvm_cpuid_entry2 *entry = cpuid_find_entry(cpuid, function, index);
     if (entry) {
-        found = true;
         ret = cpuid_entry_get_reg(entry, reg);
     }
 
@@ -448,12 +422,6 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
         }
     } else if (function == KVM_CPUID_FEATURES && reg == R_EDX) {
         ret |= 1U << KVM_HINTS_REALTIME;
-        found = 1;
-    }
-
-    /* fallback for older kernels */
-    if ((function == KVM_CPUID_FEATURES) && !found) {
-        ret = get_para_features(s);
     }
 
     return ret;