Fix some incorrect statement of MSR_KVM_ASYNC_PF_EN documentation and
state clearly the token in 'struct kvm_vcpu_pv_apf_data' of 'page ready'
event is matchted with the token in CR2 in 'page not present' event.
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
Documentation/virt/kvm/x86/msr.rst | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/Documentation/virt/kvm/x86/msr.rst b/Documentation/virt/kvm/x86/msr.rst
index f6d70f99a1a7..3aecf2a70e7b 100644
--- a/Documentation/virt/kvm/x86/msr.rst
+++ b/Documentation/virt/kvm/x86/msr.rst
@@ -193,8 +193,8 @@ data:
Asynchronous page fault (APF) control MSR.
Bits 63-6 hold 64-byte aligned physical address of a 64 byte memory area
- which must be in guest RAM and must be zeroed. This memory is expected
- to hold a copy of the following structure::
+ which must be in guest RAM. This memory is expected to hold the
+ following structure::
struct kvm_vcpu_pv_apf_data {
/* Used for 'page not present' events delivered via #PF */
@@ -231,14 +231,14 @@ data:
as regular page fault, guest must reset 'flags' to '0' before it does
something that can generate normal page fault.
- Bytes 5-7 of 64 byte memory location ('token') will be written to by the
+ Bytes 4-7 of 64 byte memory location ('token') will be written to by the
hypervisor at the time of APF 'page ready' event injection. The content
- of these bytes is a token which was previously delivered as 'page not
- present' event. The event indicates the page in now available. Guest is
- supposed to write '0' to 'token' when it is done handling 'page ready'
- event and to write 1' to MSR_KVM_ASYNC_PF_ACK after clearing the location;
- writing to the MSR forces KVM to re-scan its queue and deliver the next
- pending notification.
+ of these bytes is a token which was previously delivered in CR2 as
+ 'page not present' event. The event indicates the page is now available.
+ Guest is supposed to write '0' to 'token' when it is done handling
+ 'page ready' event and to write '1' to MSR_KVM_ASYNC_PF_ACK after
+ clearing the location; writing to the MSR forces KVM to re-scan its
+ queue and deliver the next pending notification.
Note, MSR_KVM_ASYNC_PF_INT MSR specifying the interrupt vector for 'page
ready' APF delivery needs to be written to before enabling APF mechanism
--
2.34.1
