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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c93
1 files changed, 30 insertions, 63 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index cd687395e4e..27c6ece91da 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3267,54 +3267,6 @@ static u32 get_tss_base_addr(struct kvm_vcpu *vcpu,
return vcpu->arch.mmu.gva_to_gpa(vcpu, base_addr);
}
-static int load_tss_segment32(struct kvm_vcpu *vcpu,
- struct desc_struct *seg_desc,
- struct tss_segment_32 *tss)
-{
- u32 base_addr;
-
- base_addr = get_tss_base_addr(vcpu, seg_desc);
-
- return kvm_read_guest(vcpu->kvm, base_addr, tss,
- sizeof(struct tss_segment_32));
-}
-
-static int save_tss_segment32(struct kvm_vcpu *vcpu,
- struct desc_struct *seg_desc,
- struct tss_segment_32 *tss)
-{
- u32 base_addr;
-
- base_addr = get_tss_base_addr(vcpu, seg_desc);
-
- return kvm_write_guest(vcpu->kvm, base_addr, tss,
- sizeof(struct tss_segment_32));
-}
-
-static int load_tss_segment16(struct kvm_vcpu *vcpu,
- struct desc_struct *seg_desc,
- struct tss_segment_16 *tss)
-{
- u32 base_addr;
-
- base_addr = get_tss_base_addr(vcpu, seg_desc);
-
- return kvm_read_guest(vcpu->kvm, base_addr, tss,
- sizeof(struct tss_segment_16));
-}
-
-static int save_tss_segment16(struct kvm_vcpu *vcpu,
- struct desc_struct *seg_desc,
- struct tss_segment_16 *tss)
-{
- u32 base_addr;
-
- base_addr = get_tss_base_addr(vcpu, seg_desc);
-
- return kvm_write_guest(vcpu->kvm, base_addr, tss,
- sizeof(struct tss_segment_16));
-}
-
static u16 get_segment_selector(struct kvm_vcpu *vcpu, int seg)
{
struct kvm_segment kvm_seg;
@@ -3472,20 +3424,26 @@ static int load_state_from_tss16(struct kvm_vcpu *vcpu,
}
static int kvm_task_switch_16(struct kvm_vcpu *vcpu, u16 tss_selector,
- struct desc_struct *cseg_desc,
+ u32 old_tss_base,
struct desc_struct *nseg_desc)
{
struct tss_segment_16 tss_segment_16;
int ret = 0;
- if (load_tss_segment16(vcpu, cseg_desc, &tss_segment_16))
+ if (kvm_read_guest(vcpu->kvm, old_tss_base, &tss_segment_16,
+ sizeof tss_segment_16))
goto out;
save_state_to_tss16(vcpu, &tss_segment_16);
- save_tss_segment16(vcpu, cseg_desc, &tss_segment_16);
- if (load_tss_segment16(vcpu, nseg_desc, &tss_segment_16))
+ if (kvm_write_guest(vcpu->kvm, old_tss_base, &tss_segment_16,
+ sizeof tss_segment_16))
goto out;
+
+ if (kvm_read_guest(vcpu->kvm, get_tss_base_addr(vcpu, nseg_desc),
+ &tss_segment_16, sizeof tss_segment_16))
+ goto out;
+
if (load_state_from_tss16(vcpu, &tss_segment_16))
goto out;
@@ -3495,20 +3453,26 @@ out:
}
static int kvm_task_switch_32(struct kvm_vcpu *vcpu, u16 tss_selector,
- struct desc_struct *cseg_desc,
+ u32 old_tss_base,
struct desc_struct *nseg_desc)
{
struct tss_segment_32 tss_segment_32;
int ret = 0;
- if (load_tss_segment32(vcpu, cseg_desc, &tss_segment_32))
+ if (kvm_read_guest(vcpu->kvm, old_tss_base, &tss_segment_32,
+ sizeof tss_segment_32))
goto out;
save_state_to_tss32(vcpu, &tss_segment_32);
- save_tss_segment32(vcpu, cseg_desc, &tss_segment_32);
- if (load_tss_segment32(vcpu, nseg_desc, &tss_segment_32))
+ if (kvm_write_guest(vcpu->kvm, old_tss_base, &tss_segment_32,
+ sizeof tss_segment_32))
+ goto out;
+
+ if (kvm_read_guest(vcpu->kvm, get_tss_base_addr(vcpu, nseg_desc),
+ &tss_segment_32, sizeof tss_segment_32))
goto out;
+
if (load_state_from_tss32(vcpu, &tss_segment_32))
goto out;
@@ -3523,16 +3487,20 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
struct desc_struct cseg_desc;
struct desc_struct nseg_desc;
int ret = 0;
+ u32 old_tss_base = get_segment_base(vcpu, VCPU_SREG_TR);
+ u16 old_tss_sel = get_segment_selector(vcpu, VCPU_SREG_TR);
- kvm_get_segment(vcpu, &tr_seg, VCPU_SREG_TR);
+ old_tss_base = vcpu->arch.mmu.gva_to_gpa(vcpu, old_tss_base);
+ /* FIXME: Handle errors. Failure to read either TSS or their
+ * descriptors should generate a pagefault.
+ */
if (load_guest_segment_descriptor(vcpu, tss_selector, &nseg_desc))
goto out;
- if (load_guest_segment_descriptor(vcpu, tr_seg.selector, &cseg_desc))
+ if (load_guest_segment_descriptor(vcpu, old_tss_sel, &cseg_desc))
goto out;
-
if (reason != TASK_SWITCH_IRET) {
int cpl;
@@ -3550,8 +3518,7 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
if (reason == TASK_SWITCH_IRET || reason == TASK_SWITCH_JMP) {
cseg_desc.type &= ~(1 << 1); //clear the B flag
- save_guest_segment_descriptor(vcpu, tr_seg.selector,
- &cseg_desc);
+ save_guest_segment_descriptor(vcpu, old_tss_sel, &cseg_desc);
}
if (reason == TASK_SWITCH_IRET) {
@@ -3563,10 +3530,10 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
kvm_x86_ops->cache_regs(vcpu);
if (nseg_desc.type & 8)
- ret = kvm_task_switch_32(vcpu, tss_selector, &cseg_desc,
+ ret = kvm_task_switch_32(vcpu, tss_selector, old_tss_base,
&nseg_desc);
else
- ret = kvm_task_switch_16(vcpu, tss_selector, &cseg_desc,
+ ret = kvm_task_switch_16(vcpu, tss_selector, old_tss_base,
&nseg_desc);
if (reason == TASK_SWITCH_CALL || reason == TASK_SWITCH_GATE) {