From d5c1785d2f3aabe284d91bc7fc8f0abc58525dc9 Mon Sep 17 00:00:00 2001 From: Nadav Har'El Date: Tue, 2 Aug 2011 15:54:20 +0300 Subject: KVM: L1 TSC handling KVM assumed in several places that reading the TSC MSR returns the value for L1. This is incorrect, because when L2 is running, the correct TSC read exit emulation is to return L2's value. We therefore add a new x86_ops function, read_l1_tsc, to use in places that specifically need to read the L1 TSC, NOT the TSC of the current level of guest. Note that one change, of one line in kvm_arch_vcpu_load, is made redundant by a different patch sent by Zachary Amsden (and not yet applied): kvm_arch_vcpu_load() should not read the guest TSC, and if it didn't, of course we didn't have to change the call of kvm_get_msr() to read_l1_tsc(). [avi: moved callback to kvm_x86_ops tsc block] Signed-off-by: Nadav Har'El Acked-by: Zachary Amsdem Signed-off-by: Avi Kivity --- arch/x86/include/asm/kvm_host.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b31a3417a405..6ab4241c27cb 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -630,6 +630,7 @@ struct kvm_x86_ops { void (*write_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset); u64 (*compute_tsc_offset)(struct kvm_vcpu *vcpu, u64 target_tsc); + u64 (*read_l1_tsc)(struct kvm_vcpu *vcpu); void (*get_exit_info)(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2); -- cgit v1.2.3