From 760849b1476c94da4cca5d3a5f0a1f64ffc92ba4 Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Fri, 5 Nov 2021 09:51:01 +0000 Subject: KVM: x86: Make sure KVM_CPUID_FEATURES really are KVM_CPUID_FEATURES Currently when kvm_update_cpuid_runtime() runs, it assumes that the KVM_CPUID_FEATURES leaf is located at 0x40000001. This is not true, however, if Hyper-V support is enabled. In this case the KVM leaves will be offset. This patch introdues as new 'kvm_cpuid_base' field into struct kvm_vcpu_arch to track the location of the KVM leaves and function kvm_update_kvm_cpuid_base() (called from kvm_set_cpuid()) to locate the leaves using the 'KVMKVMKVM\0\0\0' signature (which is now given a definition in kvm_para.h). Adjustment of KVM_CPUID_FEATURES will hence now target the correct leaf. NOTE: A new for_each_possible_hypervisor_cpuid_base() macro is intoduced into processor.h to avoid having duplicate code for the iteration over possible hypervisor base leaves. Signed-off-by: Paul Durrant Message-Id: <20211105095101.5384-3-pdurrant@amazon.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/processor.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 9ad2acaaae9b..726318cda082 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -807,11 +807,14 @@ static inline u32 amd_get_nodes_per_socket(void) { return 0; } static inline u32 amd_get_highest_perf(void) { return 0; } #endif +#define for_each_possible_hypervisor_cpuid_base(function) \ + for (function = 0x40000000; function < 0x40010000; function += 0x100) + static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) { uint32_t base, eax, signature[3]; - for (base = 0x40000000; base < 0x40010000; base += 0x100) { + for_each_possible_hypervisor_cpuid_base(base) { cpuid(base, &eax, &signature[0], &signature[1], &signature[2]); if (!memcmp(sig, signature, 12) && -- cgit