diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2016-11-09 17:48:15 +0100 |
|---|---|---|
| committer | Radim Krčmář <rkrcmar@redhat.com> | 2016-11-19 19:04:16 +0100 |
| commit | e3fd9a93a12a1020067a676e826877623cee8e2b (patch) | |
| tree | fcc53a18d286b78631e7764d6d8b948e355a1566 /include | |
| parent | 1650b4ebc99da4c137bfbfc531be4a2405f951dd (diff) | |
kvm: kvmclock: let KVM_GET_CLOCK return whether the master clock is in use
Userspace can read the exact value of kvmclock by reading the TSC
and fetching the timekeeping parameters out of guest memory. This
however is brittle and not necessary anymore with KVM 4.11. Provide
a mechanism that lets userspace know if the new KVM_GET_CLOCK
semantics are in effect, and---since we are at it---if the clock
is stable across all VCPUs.
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/linux/kvm.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 300ef255d1e0..4ee67cb99143 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -972,12 +972,19 @@ struct kvm_irqfd { __u8 pad[16]; }; +/* For KVM_CAP_ADJUST_CLOCK */ + +/* Do not use 1, KVM_CHECK_EXTENSION returned it before we had flags. */ +#define KVM_CLOCK_TSC_STABLE 2 + struct kvm_clock_data { __u64 clock; __u32 flags; __u32 pad[9]; }; +/* For KVM_CAP_SW_TLB */ + #define KVM_MMU_FSL_BOOKE_NOHV 0 #define KVM_MMU_FSL_BOOKE_HV 1 |