[PATCH 1/3] KVM: Drop kvm_get_gdt() in favor of generic linux function.

[PATCH 1/3] KVM: Drop kvm_get_gdt() in favor of generic linux function.

[Gleb Natapov]

Linux now has native_store_gdt() to do the same. Use it instead of
kvm local version.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
 arch/x86/include/asm/kvm_host.h |    5 -----
 arch/x86/kvm/svm.c              |    2 +-
 arch/x86/kvm/vmx.c              |    4 ++--
 arch/x86/kvm/x86.c              |    2 +-
 4 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 502fff1..e316722 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -723,11 +723,6 @@ static inline void kvm_get_idt(struct desc_ptr *table)
 	asm("sidt %0" : "=m"(*table));
 }
 
-static inline void kvm_get_gdt(struct desc_ptr *table)
-{
-	asm("sgdt %0" : "=m"(*table));
-}
-
 static inline unsigned long kvm_read_tr_base(void)
 {
 	u16 tr;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index d11ff46..7b3cee1 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -364,7 +364,7 @@ static int svm_hardware_enable(void *garbage)
 	sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
 	sd->next_asid = sd->max_asid + 1;
 
-	kvm_get_gdt(&gdt_descr);
+	native_store_gdt(&gdt_descr);
 	gdt = (struct desc_struct *)gdt_descr.address;
 	sd->tss_desc = (struct kvm_ldttss_desc *)(gdt + GDT_ENTRY_TSS);
 
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index d772476..fa48e8c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -600,7 +600,7 @@ static void reload_tss(void)
 	struct desc_ptr gdt;
 	struct desc_struct *descs;
 
-	kvm_get_gdt(&gdt);
+	native_store_gdt(&gdt);
 	descs = (void *)gdt.address;
 	descs[GDT_ENTRY_TSS].type = 9; /* available TSS */
 	load_TR_desc();
@@ -764,7 +764,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 		 * processors.
 		 */
 		vmcs_writel(HOST_TR_BASE, kvm_read_tr_base()); /* 22.2.4 */
-		kvm_get_gdt(&dt);
+		native_store_gdt(&dt);
 		vmcs_writel(HOST_GDTR_BASE, dt.address);   /* 22.2.4 */
 
 		rdmsrl(MSR_IA32_SYSENTER_ESP, sysenter_esp);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7b436c8..558eb9a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -232,7 +232,7 @@ unsigned long segment_base(u16 selector)
 	if (selector == 0)
 		return 0;
 
-	kvm_get_gdt(&gdt);
+	native_store_gdt(&gdt);
 	table_base = gdt.address;
 
 	if (selector & 4) {           /* from ldt */
-- 
1.6.5

[PATCH 2/3] KVM: fix segment_base() error checking.

[Gleb Natapov]

fix segment_base() to properly check for null segment selector and
avoid accessing NULL pointer if ldt selector in null.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
 arch/x86/kvm/x86.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 558eb9a..49f5c7b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -229,7 +229,7 @@ unsigned long segment_base(u16 selector)
 	unsigned long table_base;
 	unsigned long v;
 
-	if (selector == 0)
+	if (!(selector & ~3))
 		return 0;
 
 	native_store_gdt(&gdt);
@@ -238,6 +238,8 @@ unsigned long segment_base(u16 selector)
 	if (selector & 4) {           /* from ldt */
 		u16 ldt_selector = kvm_read_ldt();
 
+		if (!(ldt_selector & ~3))
+			return 0;
 		table_base = segment_base(ldt_selector);
 	}
 	d = (struct desc_struct *)(table_base + (selector & ~7));
-- 
1.6.5

[PATCH 3/3] KVM: move segment_base() into vmx.c

[Gleb Natapov]

segment_base() is used only by vmx so move it there.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
 arch/x86/include/asm/kvm_host.h |    9 ---------
 arch/x86/kvm/vmx.c              |   37 +++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/x86.c              |   30 ------------------------------
 3 files changed, 37 insertions(+), 39 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index e316722..ec891a2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -644,8 +644,6 @@ int emulator_write_emulated(unsigned long addr,
 			    unsigned int bytes,
 			    struct kvm_vcpu *vcpu);
 
-unsigned long segment_base(u16 selector);
-
 void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu);
 void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 		       const u8 *new, int bytes,
@@ -723,13 +721,6 @@ static inline void kvm_get_idt(struct desc_ptr *table)
 	asm("sidt %0" : "=m"(*table));
 }
 
-static inline unsigned long kvm_read_tr_base(void)
-{
-	u16 tr;
-	asm("str %0" : "=g"(tr));
-	return segment_base(tr);
-}
-
 #ifdef CONFIG_X86_64
 static inline unsigned long read_msr(unsigned long msr)
 {
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index fa48e8c..ae3217d 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -631,6 +631,43 @@ static bool update_transition_efer(struct vcpu_vmx *vmx, int efer_offset)
 	return true;
 }
 
+static unsigned long segment_base(u16 selector)
+{
+	struct desc_ptr gdt;
+	struct desc_struct *d;
+	unsigned long table_base;
+	unsigned long v;
+
+	if (!(selector & ~3))
+		return 0;
+
+	native_store_gdt(&gdt);
+	table_base = gdt.address;
+
+	if (selector & 4) {           /* from ldt */
+		u16 ldt_selector = kvm_read_ldt();
+
+		if (!(ldt_selector & ~3))
+			return 0;
+
+		table_base = segment_base(ldt_selector);
+	}
+	d = (struct desc_struct *)(table_base + (selector & ~7));
+	v = get_desc_base(d);
+#ifdef CONFIG_X86_64
+       if (d->s == 0 && (d->type == 2 || d->type == 9 || d->type == 11))
+               v |= ((unsigned long)((struct ldttss_desc64 *)d)->base3) << 32;
+#endif
+	return v;
+}
+
+static inline unsigned long kvm_read_tr_base(void)
+{
+	u16 tr;
+	asm("str %0" : "=g"(tr));
+	return segment_base(tr);
+}
+
 static void vmx_save_host_state(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 49f5c7b..7ebeaf0 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -222,36 +222,6 @@ static void drop_user_return_notifiers(void *ignore)
 		kvm_on_user_return(&smsr->urn);
 }
 
-unsigned long segment_base(u16 selector)
-{
-	struct desc_ptr gdt;
-	struct desc_struct *d;
-	unsigned long table_base;
-	unsigned long v;
-
-	if (!(selector & ~3))
-		return 0;
-
-	native_store_gdt(&gdt);
-	table_base = gdt.address;
-
-	if (selector & 4) {           /* from ldt */
-		u16 ldt_selector = kvm_read_ldt();
-
-		if (!(ldt_selector & ~3))
-			return 0;
-		table_base = segment_base(ldt_selector);
-	}
-	d = (struct desc_struct *)(table_base + (selector & ~7));
-	v = get_desc_base(d);
-#ifdef CONFIG_X86_64
-	if (d->s == 0 && (d->type == 2 || d->type == 9 || d->type == 11))
-		v |= ((unsigned long)((struct ldttss_desc64 *)d)->base3) << 32;
-#endif
-	return v;
-}
-EXPORT_SYMBOL_GPL(segment_base);
-
 u64 kvm_get_apic_base(struct kvm_vcpu *vcpu)
 {
 	if (irqchip_in_kernel(vcpu->kvm))
-- 
1.6.5

Re: [PATCH 1/3] KVM: Drop kvm_get_gdt() in favor of generic linux function.

[Avi Kivity]

On 02/25/2010 12:43 PM, Gleb Natapov wrote:
> Linux now has native_store_gdt() to do the same. Use it instead of
> kvm local version.
>    

Applied all, thanks.

-- 
error compiling committee.c: too many arguments to function