From: Andrey Smetanin asmeta...@virtuozzo.com
Added hyper-v crash msr's(HV_X64_MSR_CRASH*) data and control
geters and setters. Userspace should check that such msr's
available by check of KVM_CAP_HYPERV_MSR_CRASH capability.
User space allowed to setup Hyper-V crash ctl msr.
This msr should be setup to HV_X64_MSR_CRASH_CTL_NOTIFY
value so Hyper-V guest knows it can send crash data to host.
But Hyper-V guest notifies about crash event by writing
the same HV_X64_MSR_CRASH_CTL_NOTIFY value into crash ctl msr.
So both user space and guest writes inside ctl msr the same value
and this patch distingiush the moment of actual guest crash
by checking host initiated value from msr info. Also patch
prevents modification of crash ctl msr by guest.
Signed-off-by: Andrey Smetanin asmeta...@virtuozzo.com
Signed-off-by: Denis V. Lunev d...@openvz.org
Reviewed-by: Peter Hornyack peterhorny...@google.com
CC: Paolo Bonzini pbonz...@redhat.com
CC: Gleb Natapov g...@kernel.org
---
arch/x86/kvm/hyperv.c| 74 ++--
arch/x86/kvm/hyperv.h| 2 +-
arch/x86/kvm/x86.c | 8 +-
include/uapi/linux/kvm.h | 1 +
4 files changed, 80 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index af83c96..a8160d2 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -48,7 +48,63 @@ static bool kvm_hv_msr_partition_wide(u32 msr)
return r;
}
-static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu,
+u32 index, u64 *pdata)
+{
+ struct kvm_hv *hv = vcpu-kvm-arch.hyperv;
+
+ if (WARN_ON_ONCE(index = ARRAY_SIZE(hv-hv_crash_param)))
+ return -EINVAL;
+
+ *pdata = hv-hv_crash_param[index];
+ return 0;
+}
+
+static int kvm_hv_msr_get_crash_ctl(struct kvm_vcpu *vcpu, u64 *pdata)
+{
+ struct kvm_hv *hv = vcpu-kvm-arch.hyperv;
+
+ *pdata = hv-hv_crash_ctl;
+ return 0;
+}
+
+static int kvm_hv_msr_set_crash_ctl(struct kvm_vcpu *vcpu, u64 data, bool host)
+{
+ struct kvm_hv *hv = vcpu-kvm-arch.hyperv;
+
+ if (host)
+ hv-hv_crash_ctl = data HV_X64_MSR_CRASH_CTL_NOTIFY;
+
+ if (!host (data HV_X64_MSR_CRASH_CTL_NOTIFY)) {
+
+ vcpu_debug(vcpu, hv crash (0x%llx 0x%llx 0x%llx 0x%llx
0x%llx)\n,
+ hv-hv_crash_param[0],
+ hv-hv_crash_param[1],
+ hv-hv_crash_param[2],
+ hv-hv_crash_param[3],
+ hv-hv_crash_param[4]);
+
+ /* Send notification about crash to user space */
+ kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
+ }
+
+ return 0;
+}
+
+static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu,
+u32 index, u64 data)
+{
+ struct kvm_hv *hv = vcpu-kvm-arch.hyperv;
+
+ if (WARN_ON_ONCE(index = ARRAY_SIZE(hv-hv_crash_param)))
+ return -EINVAL;
+
+ hv-hv_crash_param[index] = data;
+ return 0;
+}
+
+static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
+bool host)
{
struct kvm *kvm = vcpu-kvm;
struct kvm_hv *hv = kvm-arch.hyperv;
@@ -101,6 +157,12 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32
msr, u64 data)
mark_page_dirty(kvm, gfn);
break;
}
+ case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
+ return kvm_hv_msr_set_crash_data(vcpu,
+msr - HV_X64_MSR_CRASH_P0,
+data);
+ case HV_X64_MSR_CRASH_CTL:
+ return kvm_hv_msr_set_crash_ctl(vcpu, data, host);
default:
vcpu_unimpl(vcpu, Hyper-V uhandled wrmsr: 0x%x data 0x%llx\n,
msr, data);
@@ -173,6 +235,12 @@ static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32
msr, u64 *pdata)
case HV_X64_MSR_REFERENCE_TSC:
data = hv-hv_tsc_page;
break;
+ case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
+ return kvm_hv_msr_get_crash_data(vcpu,
+msr - HV_X64_MSR_CRASH_P0,
+pdata);
+ case HV_X64_MSR_CRASH_CTL:
+ return kvm_hv_msr_get_crash_ctl(vcpu, pdata);
default:
vcpu_unimpl(vcpu, Hyper-V unhandled rdmsr: 0x%x\n, msr);
return 1;
@@ -217,13 +285,13 @@ static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr,
u64 *pdata)
return 0;
}
-int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
{
if (kvm_hv_msr_partition_wide(msr)) {
int r;
