KVM: x86: Add support for saving&restoring debug registers

So far user space was not able to save and restore debug registers for
migration or after reset. Plug this hole.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Jan Kiszka
2010-02-15 10:45:43 +01:00
committed by Avi Kivity
parent 48005f64d0
commit a1efbe77c1
4 changed files with 101 additions and 0 deletions

View File

@@ -1548,6 +1548,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_HYPERV_VAPIC:
case KVM_CAP_HYPERV_SPIN:
case KVM_CAP_PCI_SEGMENT:
case KVM_CAP_DEBUGREGS:
case KVM_CAP_X86_ROBUST_SINGLESTEP:
r = 1;
break;
@@ -2165,6 +2166,36 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
return 0;
}
static void kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu,
struct kvm_debugregs *dbgregs)
{
vcpu_load(vcpu);
memcpy(dbgregs->db, vcpu->arch.db, sizeof(vcpu->arch.db));
dbgregs->dr6 = vcpu->arch.dr6;
dbgregs->dr7 = vcpu->arch.dr7;
dbgregs->flags = 0;
vcpu_put(vcpu);
}
static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
struct kvm_debugregs *dbgregs)
{
if (dbgregs->flags)
return -EINVAL;
vcpu_load(vcpu);
memcpy(vcpu->arch.db, dbgregs->db, sizeof(vcpu->arch.db));
vcpu->arch.dr6 = dbgregs->dr6;
vcpu->arch.dr7 = dbgregs->dr7;
vcpu_put(vcpu);
return 0;
}
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -2343,6 +2374,29 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events);
break;
}
case KVM_GET_DEBUGREGS: {
struct kvm_debugregs dbgregs;
kvm_vcpu_ioctl_x86_get_debugregs(vcpu, &dbgregs);
r = -EFAULT;
if (copy_to_user(argp, &dbgregs,
sizeof(struct kvm_debugregs)))
break;
r = 0;
break;
}
case KVM_SET_DEBUGREGS: {
struct kvm_debugregs dbgregs;
r = -EFAULT;
if (copy_from_user(&dbgregs, argp,
sizeof(struct kvm_debugregs)))
break;
r = kvm_vcpu_ioctl_x86_set_debugregs(vcpu, &dbgregs);
break;
}
default:
r = -EINVAL;
}