summaryrefslogtreecommitdiffstats
path: root/Documentation/virtual/kvm/api.txt
diff options
context:
space:
mode:
authorDaniel Vetter <daniel.vetter@ffwll.ch>2016-12-06 10:26:30 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-12-06 10:26:48 +0100
commit75e75cbd55183ff12459666c0a1d3e71fe1481ab (patch)
treea1dc32cc055770736397f9cf9b68f9e176184943 /Documentation/virtual/kvm/api.txt
parentdrm/amdgpu: don't add files at control minor debugfs directory (diff)
parentMerge branch 'exynos-drm-next' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff)
downloadlinux-75e75cbd55183ff12459666c0a1d3e71fe1481ab.tar.xz
linux-75e75cbd55183ff12459666c0a1d3e71fe1481ab.zip
Merge remote-tracking branch 'airlied/drm-next' into drm-misc-next
Backmerge v4.9-rc8 to get at commit e94bd1736f1f60e916a85a80c0b0ebeaae36cce5 Author: Michel Dänzer <michel.daenzer@amd.com> Date: Wed Nov 30 17:30:01 2016 +0900 drm: Don't call drm_for_each_crtc with a non-KMS driver so I can apply Michel's follow-up patch. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
-rw-r--r--Documentation/virtual/kvm/api.txt11
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 739db9ab16b2..6bbceb9a3a19 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -777,6 +777,17 @@ Gets the current timestamp of kvmclock as seen by the current guest. In
conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios
such as migration.
+When KVM_CAP_ADJUST_CLOCK is passed to KVM_CHECK_EXTENSION, it returns the
+set of bits that KVM can return in struct kvm_clock_data's flag member.
+
+The only flag defined now is KVM_CLOCK_TSC_STABLE. If set, the returned
+value is the exact kvmclock value seen by all VCPUs at the instant
+when KVM_GET_CLOCK was called. If clear, the returned value is simply
+CLOCK_MONOTONIC plus a constant offset; the offset can be modified
+with KVM_SET_CLOCK. KVM will try to make all VCPUs follow this clock,
+but the exact value read by each VCPU could differ, because the host
+TSC is not stable.
+
struct kvm_clock_data {
__u64 clock; /* kvmclock current value */
__u32 flags;