From: Gioh Kim Date: Tue, 30 May 2017 13:24:45 +0000 (+0200) Subject: KVM: SVM: ignore type when setting segment registers X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=8eae9570d1d3887487be0b355d12656b46fac226;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git KVM: SVM: ignore type when setting segment registers Commit 19bca6ab75d8 ("KVM: SVM: Fix cross vendor migration issue with unusable bit") added checking type when setting unusable. So unusable can be set if present is 0 OR type is 0. According to the AMD processor manual, long mode ignores the type value in segment descriptor. And type can be 0 if it is read-only data segment. Therefore type value is not related to unusable flag. This patch is based on linux-next v4.12.0-rc3. Signed-off-by: Gioh Kim Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 183ddb235fb4..a654372efea1 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1807,7 +1807,7 @@ static void svm_get_segment(struct kvm_vcpu *vcpu, * AMD's VMCB does not have an explicit unusable field, so emulate it * for cross vendor migration purposes by "not present" */ - var->unusable = !var->present || (var->type == 0); + var->unusable = !var->present; switch (seg) { case VCPU_SREG_TR: