From: Sean Christopherson Date: Tue, 21 Sep 2021 00:02:57 +0000 (-0700) Subject: KVM: x86: Remove defunct setting of CR0.ET for guests during vCPU create X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=5ebbc470d7f33e8fba6bdb2ac8e62c49cec99108;p=uclinux-h8%2Flinux.git KVM: x86: Remove defunct setting of CR0.ET for guests during vCPU create Drop code to set CR0.ET for the guest during initialization of the guest FPU. The code was added as a misguided bug fix by commit 380102c8e431 ("KVM Set the ET flag in CR0 after initializing FX") to resolve an issue where vcpu->cr0 (now vcpu->arch.cr0) was not correctly initialized on SVM systems. While init_vmcb() did set CR0.ET, it only did so in the VMCB, and subtly did not update vcpu->cr0. Stuffing CR0.ET worked around the immediate problem, but did not fix the real bug of vcpu->cr0 and the VMCB being out of sync. That underlying bug was eventually remedied by commit 18fa000ae453 ("KVM: SVM: Reset cr0 properly on vcpu reset"). No functional change intended. Signed-off-by: Sean Christopherson Reviewed-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini Message-Id: <20210921000303.400537-5-seanjc@google.com> Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 629442e3847b..69d656125103 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10611,8 +10611,6 @@ static void fx_init(struct kvm_vcpu *vcpu) * Ensure guest xcr0 is valid for loading */ vcpu->arch.xcr0 = XFEATURE_MASK_FP; - - vcpu->arch.cr0 |= X86_CR0_ET; } void kvm_free_guest_fpu(struct kvm_vcpu *vcpu)