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Date: Mon, 16 Nov 2020 10:26:44 -0800
From: isaku.yamahata@...el.com
To: Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
"H . Peter Anvin" <hpa@...or.com>,
Paolo Bonzini <pbonzini@...hat.com>,
Vitaly Kuznetsov <vkuznets@...hat.com>,
Wanpeng Li <wanpengli@...cent.com>,
Jim Mattson <jmattson@...gle.com>,
Joerg Roedel <joro@...tes.org>, x86@...nel.org,
linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc: isaku.yamahata@...el.com, isaku.yamahata@...il.com,
Sean Christopherson <sean.j.christopherson@...el.com>
Subject: [RFC PATCH 59/67] KVM: VMX: Move AR_BYTES encoder/decoder helpers to common.h
From: Sean Christopherson <sean.j.christopherson@...el.com>
Move the AR_BYTES helpers to common.h so that future patches can reuse
them to decode/encode AR for TDX.
Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
arch/x86/kvm/vmx/common.h | 41 ++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 46 ++++-----------------------------------
2 files changed, 45 insertions(+), 42 deletions(-)
diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
index baee96abdd7e..ad106364c51f 100644
--- a/arch/x86/kvm/vmx/common.h
+++ b/arch/x86/kvm/vmx/common.h
@@ -4,6 +4,7 @@
#include <linux/kvm_host.h>
+#include <asm/kvm.h>
#include <asm/traps.h>
#include <asm/vmx.h>
@@ -121,4 +122,44 @@ static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
}
+static inline u32 vmx_encode_ar_bytes(struct kvm_segment *var)
+{
+ u32 ar;
+
+ if (var->unusable || !var->present)
+ ar = 1 << 16;
+ else {
+ ar = var->type & 15;
+ ar |= (var->s & 1) << 4;
+ ar |= (var->dpl & 3) << 5;
+ ar |= (var->present & 1) << 7;
+ ar |= (var->avl & 1) << 12;
+ ar |= (var->l & 1) << 13;
+ ar |= (var->db & 1) << 14;
+ ar |= (var->g & 1) << 15;
+ }
+
+ return ar;
+}
+
+static inline void vmx_decode_ar_bytes(u32 ar, struct kvm_segment *var)
+{
+ var->unusable = (ar >> 16) & 1;
+ var->type = ar & 15;
+ var->s = (ar >> 4) & 1;
+ var->dpl = (ar >> 5) & 3;
+ /*
+ * Some userspaces do not preserve unusable property. Since usable
+ * segment has to be present according to VMX spec we can use present
+ * property to amend userspace bug by making unusable segment always
+ * nonpresent. vmx_encode_ar_bytes() already marks nonpresent
+ * segment as unusable.
+ */
+ var->present = !var->unusable;
+ var->avl = (ar >> 12) & 1;
+ var->l = (ar >> 13) & 1;
+ var->db = (ar >> 14) & 1;
+ var->g = (ar >> 15) & 1;
+}
+
#endif /* __KVM_X86_VMX_COMMON_H */
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 85401a7eef9a..8bd71b91c6f0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -361,7 +361,6 @@ static const struct kernel_param_ops vmentry_l1d_flush_ops = {
};
module_param_cb(vmentry_l1d_flush, &vmentry_l1d_flush_ops, NULL, 0644);
-static u32 vmx_segment_access_rights(struct kvm_segment *var);
static __always_inline void vmx_disable_intercept_for_msr(struct kvm_vcpu *vcpu,
u32 msr, int type);
@@ -2736,7 +2735,7 @@ static void fix_rmode_seg(int seg, struct kvm_segment *save)
vmcs_write16(sf->selector, var.selector);
vmcs_writel(sf->base, var.base);
vmcs_write32(sf->limit, var.limit);
- vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(&var));
+ vmcs_write32(sf->ar_bytes, vmx_encode_ar_bytes(&var));
}
static void enter_rmode(struct kvm_vcpu *vcpu)
@@ -3131,7 +3130,6 @@ int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- u32 ar;
if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
*var = vmx->rmode.segs[seg];
@@ -3145,23 +3143,7 @@ void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
var->base = vmx_read_guest_seg_base(vmx, seg);
var->limit = vmx_read_guest_seg_limit(vmx, seg);
var->selector = vmx_read_guest_seg_selector(vmx, seg);
- ar = vmx_read_guest_seg_ar(vmx, seg);
- var->unusable = (ar >> 16) & 1;
- var->type = ar & 15;
- var->s = (ar >> 4) & 1;
- var->dpl = (ar >> 5) & 3;
- /*
- * Some userspaces do not preserve unusable property. Since usable
- * segment has to be present according to VMX spec we can use present
- * property to amend userspace bug by making unusable segment always
- * nonpresent. vmx_segment_access_rights() already marks nonpresent
- * segment as unusable.
- */
- var->present = !var->unusable;
- var->avl = (ar >> 12) & 1;
- var->l = (ar >> 13) & 1;
- var->db = (ar >> 14) & 1;
- var->g = (ar >> 15) & 1;
+ vmx_decode_ar_bytes(vmx_read_guest_seg_ar(vmx, seg), var);
}
static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
@@ -3187,26 +3169,6 @@ int vmx_get_cpl(struct kvm_vcpu *vcpu)
}
}
-static u32 vmx_segment_access_rights(struct kvm_segment *var)
-{
- u32 ar;
-
- if (var->unusable || !var->present)
- ar = 1 << 16;
- else {
- ar = var->type & 15;
- ar |= (var->s & 1) << 4;
- ar |= (var->dpl & 3) << 5;
- ar |= (var->present & 1) << 7;
- ar |= (var->avl & 1) << 12;
- ar |= (var->l & 1) << 13;
- ar |= (var->db & 1) << 14;
- ar |= (var->g & 1) << 15;
- }
-
- return ar;
-}
-
void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -3241,7 +3203,7 @@ void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
if (is_unrestricted_guest(vcpu) && (seg != VCPU_SREG_LDTR))
var->type |= 0x1; /* Accessed */
- vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(var));
+ vmcs_write32(sf->ar_bytes, vmx_encode_ar_bytes(var));
out:
vmx->emulation_required = emulation_required(vcpu);
@@ -3288,7 +3250,7 @@ static bool rmode_segment_valid(struct kvm_vcpu *vcpu, int seg)
var.dpl = 0x3;
if (seg == VCPU_SREG_CS)
var.type = 0x3;
- ar = vmx_segment_access_rights(&var);
+ ar = vmx_encode_ar_bytes(&var);
if (var.base != (var.selector << 4))
return false;
--
2.17.1
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