Re: [PATCH v4 2/3] KVM-INTEL: Add new module vmcsinfo-intel to fill VMCSINFO

[HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>]

From: Yanfei Zhang <zhangyanfei@cn.fujitsu.com>
Subject: [PATCH v4 2/3] KVM-INTEL: Add new module vmcsinfo-intel to fill VMCSINFO
Date: Wed, 4 Jul 2012 18:05:19 +0800

> Besides, this patch also exports vmcs revision identifier via
> /sys/devices/system/cpu/vmcs_id and offsets of fields via
> /sys/devices/system/cpu/vmcs/.
> Individual offsets are contained in subfiles named by the filed's
> encoding, e.g.: /sys/devices/cpu/vmcs/0800

According to the discussion starting from

http://lkml.indiana.edu/hypermail/linux/kernel/1105.3/00749.html

system can be composed of CPUs with different steppings or differnet
microcode revisions. Becase of the nature that it's hided in the
specification, I suspect layout of vmcs could change across different
steppings or microcode revisions. Then, the interface needs to be
changed as per-cpu like

   /sys/devices/cpu/cpu0/vmcs/0800
   /sys/devices/cpu/cpu1/vmcs/0800
   ...
   /sys/devices/cpu/cpuN/vmcs/0800

Also, processing of vmcsinfo initialization needs to be done per cpu,
and can be triggered when cpu is added not when kvm module is loaded.

Thanks.
HATAYAMA, Daisuke