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Subject[PATCH v2 04/10] KVM: x86: Remove defunct setting of CR0.ET for guests during vCPU create
From
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 <seanjc@google.com>
---
arch/x86/kvm/x86.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ab907a0b9eeb..e0bff5473813 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10628,8 +10628,6 @@ 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)
--
2.33.0.464.g1972c5931b-goog
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