[PATCH 25/41] KVM: Modify guest segments after potentially switching modes

Avi Kivity
2007-04-01T14:35:22Z

The SET_SREGS ioctl modifies both cr0.pe (real mode/protected mode) and
guest segment registers. Since segment handling is modified by the mode on
Intel procesors, update the segment registers after the mode switch has taken
place.

Signed-off-by: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
---
drivers/kvm/kvm_main.c | 20 ++++++++++----------
1 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 5ada7aa..12c3388 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1895,16 +1895,6 @@ static int kvm_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,

vcpu_load(vcpu);

- set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
- set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
- set_segment(vcpu, &sregs->es, VCPU_SREG_ES);
- set_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
- set_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
- set_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
-
- set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
- set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
-
dt.limit = sregs->idt.limit;
dt.base = sregs->idt.base;
kvm_arch_ops->set_idt(vcpu, &dt);
@@ -1944,6 +1934,16 @@ static int kvm_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
if (vcpu->irq_pending[i])
__set_bit(i, &vcpu->irq_summary);

+ set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
+ set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
+ set_segment(vcpu, &sregs->es, VCPU_SREG_ES);
+ set_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
+ set_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
+ set_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
+
+ set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
+ set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
+
vcpu_put(vcpu);

return 0;