From bcf600ca8d21e49af21fec5d2cf3927d6f62d048 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 2 Mar 2020 15:56:49 -0800 Subject: KVM: x86: Remove the unnecessary loop on CPUID 0x7 sub-leafs Explicitly handle CPUID 0x7 sub-leaf 1. The kernel is currently aware of exactly one feature in CPUID 0x7.1, which means there is room for another 127 features before CPUID 0x7.2 will see the light of day, i.e. the looping is likely to be dead code for years to come. Reviewed-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'arch/x86/kvm/cpuid.c') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index f6d3121656cc..cce78723376c 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -536,11 +536,9 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) if (boot_cpu_has(X86_FEATURE_AMD_SSBD)) cpuid_entry_set(entry, X86_FEATURE_SPEC_CTRL_SSBD); - for (i = 1, max_idx = entry->eax; i <= max_idx; i++) { - if (WARN_ON_ONCE(i > 1)) - break; - - entry = do_host_cpuid(array, function, i); + /* KVM only supports 0x7.0 and 0x7.1, capped above via min(). */ + if (entry->eax == 1) { + entry = do_host_cpuid(array, function, 1); if (!entry) goto out; -- cgit v1.2.3