[PATCH RESEND] i386/kvm: support guest access CORE cstate

From: Wanpeng Li
Date: Sun Jul 14 2019 - 21:28:56 EST


From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

Allow guest reads CORE cstate when exposing host CPU power management capabilities
to the guest. PKG cstate is restricted to avoid a guest to get the whole package
information in multi-tenant scenario.

Cc: Eduardo Habkost <ehabkost@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
linux-headers/linux/kvm.h | 4 +++-
target/i386/kvm.c | 3 ++-
2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index b53ee59..d648fde 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -696,9 +696,11 @@ struct kvm_ioeventfd {
#define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0)
#define KVM_X86_DISABLE_EXITS_HLT (1 << 1)
#define KVM_X86_DISABLE_EXITS_PAUSE (1 << 2)
+#define KVM_X86_DISABLE_EXITS_CSTATE (1 << 3)
#define KVM_X86_DISABLE_VALID_EXITS (KVM_X86_DISABLE_EXITS_MWAIT | \
KVM_X86_DISABLE_EXITS_HLT | \
- KVM_X86_DISABLE_EXITS_PAUSE)
+ KVM_X86_DISABLE_EXITS_PAUSE | \
+ KVM_X86_DISABLE_EXITS_CSTATE)

/* for KVM_ENABLE_CAP */
struct kvm_enable_cap {
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 3b29ce5..49a0cc1 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -1645,7 +1645,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
if (disable_exits) {
disable_exits &= (KVM_X86_DISABLE_EXITS_MWAIT |
KVM_X86_DISABLE_EXITS_HLT |
- KVM_X86_DISABLE_EXITS_PAUSE);
+ KVM_X86_DISABLE_EXITS_PAUSE |
+ KVM_X86_DISABLE_EXITS_CSTATE);
}

ret = kvm_vm_enable_cap(s, KVM_CAP_X86_DISABLE_EXITS, 0,
--
2.7.4