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-rw-r--r--Documentation/virtual/kvm/api.txt11
-rw-r--r--Documentation/virtual/kvm/locking.txt12
-rw-r--r--Documentation/virtual/kvm/msr.txt9
-rw-r--r--Documentation/virtual/kvm/review-checklist.txt4
4 files changed, 32 insertions, 4 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;
diff --git a/Documentation/virtual/kvm/locking.txt b/Documentation/virtual/kvm/locking.txt
index f2491a8c68b4..e5dd9f4d6100 100644
--- a/Documentation/virtual/kvm/locking.txt
+++ b/Documentation/virtual/kvm/locking.txt
@@ -4,7 +4,17 @@ KVM Lock Overview
1. Acquisition Orders
---------------------
-(to be written)
+The acquisition orders for mutexes are as follows:
+
+- kvm->lock is taken outside vcpu->mutex
+
+- kvm->lock is taken outside kvm->slots_lock and kvm->irq_lock
+
+- kvm->slots_lock is taken outside kvm->irq_lock, though acquiring
+ them together is quite rare.
+
+For spinlocks, kvm_lock is taken outside kvm->mmu_lock. Everything
+else is a leaf: no other lock is taken inside the critical sections.
2: Exception
------------
diff --git a/Documentation/virtual/kvm/msr.txt b/Documentation/virtual/kvm/msr.txt
index 2a71c8f29f68..0a9ea515512a 100644
--- a/Documentation/virtual/kvm/msr.txt
+++ b/Documentation/virtual/kvm/msr.txt
@@ -208,7 +208,9 @@ MSR_KVM_STEAL_TIME: 0x4b564d03
__u64 steal;
__u32 version;
__u32 flags;
- __u32 pad[12];
+ __u8 preempted;
+ __u8 u8_pad[3];
+ __u32 pad[11];
}
whose data will be filled in by the hypervisor periodically. Only one
@@ -232,6 +234,11 @@ MSR_KVM_STEAL_TIME: 0x4b564d03
nanoseconds. Time during which the vcpu is idle, will not be
reported as steal time.
+ preempted: indicate the vCPU who owns this struct is running or
+ not. Non-zero values mean the vCPU has been preempted. Zero
+ means the vCPU is not preempted. NOTE, it is always zero if the
+ the hypervisor doesn't support this field.
+
MSR_KVM_EOI_EN: 0x4b564d04
data: Bit 0 is 1 when PV end of interrupt is enabled on the vcpu; 0
when disabled. Bit 1 is reserved and must be zero. When PV end of
diff --git a/Documentation/virtual/kvm/review-checklist.txt b/Documentation/virtual/kvm/review-checklist.txt
index a850986ed684..a83b27635fdd 100644
--- a/Documentation/virtual/kvm/review-checklist.txt
+++ b/Documentation/virtual/kvm/review-checklist.txt
@@ -1,8 +1,8 @@
Review checklist for kvm patches
================================
-1. The patch must follow Documentation/CodingStyle and
- Documentation/SubmittingPatches.
+1. The patch must follow Documentation/process/coding-style.rst and
+ Documentation/process/submitting-patches.rst.
2. Patches should be against kvm.git master branch.
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